GEORGIUS AGRICOLA
TRANSLATED FROM THE FIRST LATIN EDITION OF 1556
with
Biographical Introduction, Annotations and Appendices upon
the
Development of Mining Methods, Metallurgical
Processes, Geology,
Mineralogy & Mining Law
from the earliest times to the 16th
Century
BY
A. B. Stanford University, Member American Institute of Mining Engineers,
Mining and Metallurgical Society of America, Société des
Ingéniéurs
Civils de France, American Institute of Civil
Engineers,
Fellow Royal Geographical Society, etc., etc.
AND
A. B.
Stanford University, Member American Association for the
Advancement of
Science, The National Geographical Society,
Royal Scottish Geographical
Society, etc., etc.
1950
NEW YORK
JOHN CASPAR BRANNER Ph.D.,
This New 1950 Edition
of DE RE METALLICA is a complete
and
unchanged reprint of the transla
tion published by The Mining
Magazine,
London, in 1912. It has been made avail
able through
the kind permission of Honor
able Herbert C. Hoover and Mr.
Edgar
Rickard, Author and Publisher, respec
tively, of the
original volume.
FÜR
WISSENSCHAFTSGESCHICHTE
Bibliothek
PRINTED IN THE UNITED STATES OF AMERICA
There are three objectives in translation of works
of this character: to
give a faithful, literal trans
lation of the author's statements;
to give these
in a manner which will interest the reader; and to
preserve, so far as is possible, the style of the
original text. The task has been doubly difficult
in this work because, in using Latin,
the author
availed himself of a medium which had ceased to
expand
a thousand years before his subject had in
many particulars come into
being; in consequence he was in difficulties
with a large number of
ideas for which there were no corresponding
words in the vocabulary at
his command, and instead of adopting into the
text his native German
terms, he coined several hundred Latin expressions
to answer his needs. It is upon this rock that most former attempts at
translation have been
wrecked. Except for a very small number, we
believe we have been able to discover
the intended meaning of such
expressions from a study of the context,
assisted by a very incomplete
glossary prepared by the author himself,
and by an exhaustive investigation
into the literature of these
subjects during the sixteenth and seventeenth
centuries. That discovery in this particular has been only gradual and
obtained
after much labour, may be indicated by the fact that the entire
text
has been re-typewritten three times since the original, and some
parts
more often; and further, that the printer's proof has been thrice revised.
We have found some English equivalent, more or less satisfactory, for
practically all such terms, except those of weights, the varieties of
veins,
and a few minerals. In the matter of weights we have introduced the
original Latin, because
it is impossible to give true equivalents and avoid the
fractions of
reduction; and further, as explained in the Appendix on Weights it
is
impossible to say in many cases what scale the Author had in mind. The
English nomenclature to be adopted has given great difficulty, for
various
reasons; among them, that many methods and processes described
have
never been practised in English-speaking mining communities, and
so had no
representatives in our vocabulary, and we considered the
introduction of
German terms undesirable; other methods and processes
have become
obsolete and their descriptive terms with them, yet we
wished to avoid
the introduction of obsolete or unusual English; but of
the greatest
importance of all has been the necessity to avoid
rigorously such modern
technical terms as would imply a greater
scientific understanding than the
period possessed.
Agricola's Latin, while mostly free from mediæval corruption, is
some
what tainted with German construction. Moreover some portions have not
that the writing
of the work extended over a period of twenty years, suffic
iently
explains the considerable variation in style. The technical descriptions
in the later books often take the form of
House-that-Jack-built sentences
which have had to be at least partially
broken up and the subject
occasionally re-introduced. Ambiguities were also sometimes found which it
was necessary to carry on
into the translation. Despite these criticisms we
must, however, emphasize that Agricola was
infinitely clearer in his style
than his contemporaries upon such
subjects, or for that matter than his
successors in almost any language
for a couple of centuries. All of the
illustrations and display letters of the original have been
reproduced and
the type as closely approximates to the original as the
printers have been
able to find in a modern font.
There are no footnotes in the original text, and Mr.
Hoover is responsible
for them all. He has attempted in them to give not only such comment
as would tend to
clarify the text, but also such information as we have
been able to
discover with regard to the previous history of the subjects
mentioned. We have confined the historical notes to the time prior to
Agricola,
because to have carried them down to date in the briefest manner
would
have demanded very much more space than could be allowed. In the
examination of such technical and historical material one is
appalled at the
flood of mis-information with regard to ancient arts
and sciences which has
been let loose upon the world by the hands of
non-technical translators and
commentators. At an early stage we considered that we must justify any
divergence of
view from such authorities, but to limit the already alarming
volume of
this work, we later felt compelled to eliminate most of such
dis
cussion. When the half-dozen most important of the ancient works bearing
upon
science have been translated by those of some scientific experience,
such questions will, no doubt, be properly settled.
We need make no apologies for
During 180 years
it was not superseded as the text-book and guide to
miners and metallurgists,
for until Schlüter's great work on
metallurgy in 1738 it had no equal. That
it passed through some ten editions in three languages at a period
when the
printing of such a volume was no ordinary undertaking, is in
itself sufficient
evidence of the importance in which it was held, and
is a record that no other
volume upon the same subjects has equalled
since. A large proportion of the
technical data given by Agricola was either
entirely new, or had not been
given previously with sufficient detail
and explanation to have enabled a
worker in these arts himself to
perform the operations without further guid
ance. Practically the whole of it must have been given from personal
ex
perience and observation, for the scant library at his service
can be appreci
ated from his own Preface. Considering the part which the metallic arts
have played in human
history, the paucity of their literature down to
Agricola's time is
amazing. No doubt the arts were jealously guarded by
their practitioners as a
sort of stock-in-trade, and it is also probable that
those who had
knowledge were not usually of a literary turn of mind; and,
interested in the description of industrial
pursuits. Moreover, in those
thousands of years prior to printing, the tedious and
expensive transcription of
manuscripts by hand was mostly applied to
matters of more general interest,
and therefore many writings may have
been lost in consequence. In fact,
such was the fate of the works of Theophrastus and Strato on
these subjects.
We have prepared a short sketch of Agricola's life and times, not only
to give some indication of his learning and character, but also of his
considerable position in the community in which he lived. As no appreciation
of Agricola's stature among the founders of science
can be gained without
consideration of the advance which his works
display over those of his
predecessors, we therefore devote some
attention to the state of knowledge
of these subjects at the time by
giving in the Appendix a short review of the
literature then extant and
a summary of Agricola's other writings. To serve the
bibliophile we present such data as we have been able to
collect it with regard
to the various editions of his works. The full titles of the works quoted in
the footnotes under simply
authors' names will be found in this Appendix.
We feel that it is scarcely doing Agricola justice to publish
MetallícaWhile it is of the most general interest of all of his works,
yet, from
the point of view of pure science,
Ortu et CausísIt is
unfortunate that Agricola's own countrymen have not given to the
world
competent translations into German, as his work has too often
been judged
by the German translations, the infidelity of which appears
in nearly every
paragraph.
We do not present
The methods and processes have long since been superseded; yet surely such
a milestone on the road of development of one of the two most basic of
human
industrial activities is more worthy of preservation than the
thousands of
volumes devoted to records of human destruction. To those interested in
the history of their own profession we need make
no apologies, except
for the long delay in publication. For this we put forward the necessity of
active endeavour in many
directions; as this book could be but a labour of
love, it has had to
find the moments for its execution in night hours, week
ends, and
holidays, in all extending over a period of about five years. If the
work serves to strengthen the traditions of one of the most
important and
least recognized of the world's professions we shall be
amply repaid.
It is our pleasure to acknowledge our obligations to Professor H. R.
Fairclough, of Stanford University, for perusal of and suggestions upon
the first
chapter; and to those whom we have engaged from time to time
for one service
or another, chiefly bibliographical work and collateral
translation. We are
also sensibly obligated to the printers, Messrs. Frost & Sons, for their patience
and interest, and for their
willingness to bend some of the canons of modern
printing, to meet the
demands of the 16th Century.
THE RED HOUSE,
HORNTON STREET, LONDON.
BIOGRAPHY.
Georgius Agricola was born at Glauchau, in
Saxony, on March 24th, 1494,
and therefore entered
the world when it was still upon the threshold of
the
Renaissance; Gutenberg's first book had been print
ed but
forty years before; the Humanists had but
begun that stimulating
criticism which awoke the
Reformation; Erasmus, of Rotterdam, who was
sub
sequently to become Agricola's friend and patron,
was just
completing his student days. The Refor
mation itself was yet to come, but it was not long
delayed, for Luther
was born the year before Agricola, and through him
Agricola's home
land became the cradle of the great movement; nor
did Agricola escape being
drawn into the conflict. Italy, already awake with the new classical revival, was
still a busy
workshop of antiquarian research, translation, study, and
publication,
and through her the Greek and Latin Classics were only
now available
for wide distribution. Students from the rest of Europe,
among them at a later time Agricola
himself, flocked to the Italian
Universities, and on their return
infected their native cities with the newly
awakened learning. At Agricola's birth Columbus had just returned from his
great discovery,
and it was only three years later that Vasco Da Gama rounded
Cape Good
Hope. Thus these two foremost explorers had only initiated
that greatest
period of geographical expansion in the world's history. A few
dates will recall how far this exploration extended during
Agricola's lifetime. Balboa first saw the Pacific in 1513; Cortes entered the City of Mexico in
1520; Magellan entered the Pacific in the same year; Pizarro penetrated
into Peru in 1528; De Soto landed in Florida in 1539, and Potosi was
dis
covered in 1546. Omitting the sporadic settlement on the St. Lawrence by
Cartier in 1541, the settlement of North America did not
begin for a quarter
of a century after Agricola's death. Thus the revival of learning, with its
train of Humanism, the
Reformation, its stimulation of exploration and the
re-awakening of the
arts and sciences, was still in its infancy with Agricola.
We know practically nothing of Agricola's antecedents or his youth.
His
real name was Georg Bauer (“peasant”), and it was
probably Latinized by
his teachers, as was the custom of the time. His own brother, in receipts
and in
them refers to his brother “Agricola.” He entered the University
of
Leipsic at the age of twenty, and after about three and one-half
years' attendance
there gained the degree of In 1518 he became Vice
Principal of the Municipal School at
Zwickau, where he taught Greek and Latin. In 1520 he became Principal, and among his assistants was Johannes
Förster,
better known as Luther's collaborator in the translation
of the Bible. During
this time our author prepared and published a small Latin
GrammarIn
1522 he removed to Leipsic to become a lecturer in the University
under his
friend, Petrus Mosellanus, at whose death in 1524 he went to
Italy for the
further study of Philosophy, Medicine, and the Natural
Sciences. Here he
remained for nearly three years, from 1524 to 1526. He visited
the Universities
of Bologna, Venice, and probably Padua, and at these
institutions received
his first inspiration to work in the sciences,
for in a letter
Casibrotius to Erasmus we learn that he was engaged upon a revision of
Galen. It was about this time that he made the acquaintance of Erasmus, who had
settled at Basel as Editor for Froben's press.
In 1526 Agricola returned to Zwickau, and in 1527 he was chosen town
physician at Joachimsthal. This little city in Bohemia is located on the
eastern slope of the
Erzgebirge, in the midst of the then most prolific metal
mining
district of Central Europe. Thence to Freiberg is but fifty miles,
and the same radius from that
city would include most of the mining towns
so frequently mentioned in
and Altenberg—and not far
away were Marienberg, Gottesgab, and Platten. Joachimsthal was a booming mining camp, founded but eleven years before
Agricola's arrival, and already having several thousand inhabitants. Accord
ing to Agricola's own statement
medical
duties in visiting the mines and smelters, in reading up in the Greek and
Latin authors all references to mining, and in association with the
most learned
among the mining folk. Among these was one Lorenz Berman, whom Agricola
afterward set up as the
“learned miner” in his dialogue This
book was first published by Froben at Basel in 1530, and was a
sort of
catechism on mineralogy, mining terms, and mining lore. The book was
apparently first submitted to the great Erasmus, and the
publication arranged
by him, a warm letter of approval by him appearing
at the beginning of the
bookIn 1533 he published
this being a
discussion of Roman and Greek weights and measures. At
about this time he began
twenty-five years.
Agricola did not confine his interest entirely to medicine and mining,
for during this period he composed a pamphlet upon the Turks, urging
their
extermination by the European powers. This work was no doubt inspired by
the Turkish siege of Vienna in 1529.
It appeared first in German in 1531,
and in Latin—in which it was
originally written—in 1538, and passed through
many subsequent
editions.
At this time, too, he became interested in the God's Gift mine at
Albertham, which was discovered in 1530. Writing in 1545, he says
“We, as a shareholder,
through the goodness of God, have enjoyed the
proceeds of this God's
Gift since the very time when the mine began first
to bestow such
riches.”
Agricola seems to have resigned his position at Joachimsthal in about
1530, and to have devoted the next two or three years to travel and
study
among the mines. About 1533 he became city physician of Chemnitz, in
Saxony, and here he
resided until his death in 1555. There is but little
record of his
activities during the first eight or nine years of his residence in
this city. He must have been engaged upon the study of his subjects and
the
preparation of his books, for they came on with great rapidity soon after.
He was frequently consulted on matters of mining engineering, as, for
instance,
we learn, from a letter written by a certain Johannes
Hordeborch
Duke
Henry of Brunswick applied to him with regard to the method for
working
mines in the Upper Harz.
In 1543 he married Anna, widow of Matthias Meyner, a petty tithe
official; there is some reason to believe from a letter published by
Schmid,
that Anna was his
second wife, and that he was married the first time at
Joachimsthal. He seems to have had several children, for he commends his
young
children to the care of the Town Council during his absence at the
war
in 1547. In addition to these, we know that a son, Theodor, was born
in
1550; a daughter, Anna, in 1552; another daughter, Irene, was buried at
Chemnitz in 1555; and in 1580 his widow and three children—Anna,
Valerius, and Lucretia—were still living.
In 1544 began the publication of the series of books to which Agricola
owes his position. The first volume comprised five works and was finally
issued in 1546; it
was subsequently considerably revised, and re-issued in 1558.
These
works were:
first work on physical geology;
four
“books,” on subterranean waters and gases;
ten
“books,” the first systematic mineralogy;
in two “books,” devoted largely to the history of metals
and topographical
mineralogy; a new edition of
Metallícarum Interpretatio,
and
metallurgical terms. Another work,
usually published with It
is not a very effective
basis of either geologic or zoologic classi
fication. Despite many public activities, Agricola apparently completed
did it appear
until a year after his death in 1555. But we give further details
on
the preparation of this work on p. xv.
During this period he found time
to prepare a small medical work,
details of which appear in the Appendix. There are other works by Agricola re
ferred to by sixteenth century
writers, but so far we have not been able to find
them although they
may exist. Such data as we have, is given in the appendix.
As a young man, Agricola seems to have had some tendencies toward
liberalism in religious matters, for while at Zwickau he composed some
anti
Popish Epigrams; but after his return to Leipsic he apparently
never wavered,
and steadily refused to accept the Lutheran Reformation. To many even
liberal scholars of the day, Luther's doctrines appeared
wild and demagogic. Luther was not a scholarly man; his addresses were to the masses; his Latin
was execrable. Nor did the bitter dissensions over hair-splitting theology in
the
Lutheran Church after Luther's death tend to increase respect for the
movement among the learned. Agricola was a scholar of wide attainments,
a deep-thinking, religious
man, and he remained to the end a staunch Catholic,
despite the general
change of sentiment among his countrymen. His leanings
were toward such men as his friend the humanist, Erasmus. That he had
the courage of his convictions is shown in the dedication of
where he addresses to his friend, Duke Maurice, the pious advice that
the
dissensions of the Germans should be composed, and that the Duke
should return
to the bosom of the Church those who had been torn from
her, and adds: “Yet
I do not wish to become confused by these
turbulent waters, and be led to
offend anyone. It is more advisable to check my utterances.” As he
became older
he may have become less tolerant in religious matters, for he
did not
seem to show as much patience in the discussion of ecclesiastical topics
as he must have possessed earlier, yet he maintained to the end the
respect
and friendship of such great Protestants as Melanchthon,
Camerarius, Fabricius,
and many others.
In 1546, when he was at the age of 52, began Agricola's activity in
public life, for in that year he was elected a Burgher of Chemnitz; and
in the
same year Duke Maurice appointed him Burgomaster—an office
which
he held for four terms. Before one can gain an insight into his political
services, and
incidentally into the character of the man, it is necessary to
understand the politics of the time and his part therein, and to bear
in mind
always that he was a staunch Catholic under a Protestant
Sovereign in a
State seething with militant Protestantism.
Saxony had been divided in 1485 between the Princes Ernest and Albert,
the former taking the Electoral dignity and the major portion of the
Princi
pality. Albert the Brave, the younger brother and Duke of Saxony, obtained
the
subordinate portion, embracing Meissen, but subject to the Elector.
The Elector Ernest was succeeded in 1486 by Frederick the Wise, and under
This
Elector was succeeded in 1525 by his brother John, who was in turn
succeeded
by his son John Frederick in 1532. Of more immediate interest
to this subject
is the Albertian line of Saxon Dukes who ruled Meissen,
for in that Princi
pality Agricola was born and lived, and his
political fortunes were associated
with this branch of the Saxon House. Albert was succeeded in 1505 by his
son George, “The
Bearded,” and he in turn by his brother Henry, the last
of the
Catholics, in 1539, who ruled until 1541. Henry was succeeded in 1541
by his Protestant son Maurice, who was the Patron of Agricola.
At about this time Saxony was drawn into the storms which rose from
the
long-standing rivalry between Francis I., King of France, and Charles V.
of Spain. These two potentates came to the throne in the same year (1515),
and
both were candidates for Emperor of that loose Confederation known
as
the Holy Roman Empire. Charles was elected, and intermittent wars
between these two Princes
arose—first in one part of Europe, and then in
another. Francis finally formed an alliance with the Schmalkalden League
of
German Protestant Princes, and with the Sultan of Turkey, against Charles.
In 1546 Maurice of Meissen, although a Protestant, saw his best interest in
a secret league with Charles against the other Protestant Princes, and
pro
ceeded (the Schmalkalden War) to invade the domains of his
superior and
cousin, the Elector Frederick. The Emperor Charles proved successful in
this war, and Maurice was
rewarded, at the Capitulation of Wittenberg in 1547,
by being made
Elector of Saxony in the place of his cousin. Later on, the
Elector Maurice found the association with Catholic
Charles unpalatable, and
joined in leading the other Protestant princes
in war upon him, and on the
defeat of the Catholic party and the peace
of Passau, Maurice became
acknowledged as the champion of German
national and religious freedom. He was succeeded by his brother Augustus in 1553.
Agricola was much favoured by the Saxon Electors, Maurice and
Augustus. He dedicates most of his works to them, and shows much gratitude
for
many favours conferred upon him. Duke Maurice presented to him a
house and plot in Chemnitz, and in a
letter dated June 14th, 1543,
nection therewith, says: “ . . . . that he may enjoy his
life-long a
freehold house unburdened by all burgher rights and other
municipal ser
vice, to be used by him and inhabited as a free
dwelling, and that he may
also, for the necessities of his household
and of his wife and servants, brew
his own beer free, and that he may
likewise purvey for himself and his
household foreign beer and also
wine for use, and yet he shall not sell any
such beer. . . . We have
taken the said Doctor under our especial
protection and care for our
life-long, and he shall not be summoned before
any Court of Justice,
but only before us and our Councillor. . . .”
Agricola was made Burgomaster of Chemnitz in 1546. A letter
Fabricius to Meurer, dated May
19th, 1546, says that Agricola had been This would be Maurice,
and it is all the more a tribute to the high
respect with which Agricola was
held, for, as said before, he was a
consistent Catholic, and Maurice a Protestant
Prince. In this same year the Schmalkalden War broke out, and Agricola
was
called to personal attendance upon the Duke Maurice in a diplomatic
and
advisory capacity. In 1546 also he was a member of the Diet of Freiberg,
and was summoned
to Council in Dresden. The next year he continued, by
the Duke's command, Burgomaster at
Chemnitz, although he seems to have
been away upon Ducal matters most
of the time. The Duke addresses
the Chemnitz
Council in March, 1547: “We hereby make known to you
that we are
in urgent need of your Burgomaster, Dr. Georgius Agricola,
with us. It is, therefore, our will that you should yield him up and forward
him
that he should with the utmost haste set forth to us here near
Freiberg.”
He was sent on various missions from the Duke to the
Emperor Charles, to
King Ferdinand of Austria, and to other Princes in
matters connected with the
war—the fact that he was a Catholic
probably entering into his appointment
to such missions. Chemnitz was occupied by the troops of first one side, then
the other,
despite the great efforts of Agricola to have his own town specially
defended. In April, 1547, the war came to an end in the Battle of Mühlberg,
but Agricola was apparently not relieved of his Burgomastership until
the
succeeding year, for he wrote his friend Wolfgang Meurer, in April,
1548,
that he “was
now relieved.” His public duties did not end, however, for he
attended the Diet of Leipzig in 1547 and in 1549, and was at the Diet
at Torgau in 1550. In 1551 he was again installed as Burgomaster; and
in
1553, for the fourth time, he became head of the Municipality, and
during
this year had again to attend the Diets at Leipzig and Dresden,
representing
his city. He apparently now had a short relief from public duties, for it is
not
until 1555, shortly before his death, that we find him again attending a
Diet at Torgau.
Agricola died on November 21st, 1555. A letter
Fabricius, to Melanchthon,
announcing this event, states: “We lost, on
November 21st, that
distinguished ornament of our Fatherland, Georgius
Agricola, a man of
eminent intellect, of culture and of judgment. He
attained the age of 62. He who since the days of childhood had
enjoyed
robust health was carried off by a four-days' fever. He had previously
suffered from no disease except inflammation of the
eyes, which he brought
upon himself by untiring study and insatiable
reading. . . I know that
you loved the soul of this man, although in
many of his opinions, more
especially in religious and spiritual
welfare, he differed in many points from
our own. For he despised our Churches, and would not be with us in the
Communion
of the Blood of Christ. Therefore, after his death, at the
command of the Prince, which was
given to the Church inspectors and
carried out by Tettelbach as a loyal
servant, burial was refused him, and not
. . . . I have always admired the genius of this man, so distinguished
in our sciences and in the whole realm of Philosophy—yet I wonder
at his
religious views, which were compatible with reason, it is true,
and were
dazzling, but were by no means compatible with truth. . . . He
would not tolerate with patience that anyone should discuss
ecclesiastical
matters with him.” This action of the authorities
in denying burial to one
of their most honored citizens, who had been
ever assiduous in furthering
the welfare of the community, seems
strangely out of joint. Further, the
Elector Augustus, although a Protestant Prince, was
Agricola's warm friend,
as evidenced by his letter of but a few months
before (see p. xv). However,
Catholics were then few in number at Chemnitz, and the
feeling ran high at the
time, so possibly the Prince was afraid of
public disturbances. Hofmann
explains this
occurrence in the following words:—“The feelings of Chemnitz
citizens, who were almost exclusively Protestant, must certainly be
taken
into account. They may have raised objections to the solemn interment of
a Catholic in
the Protestant Cathedral Church of St. Jacob, which had,
perhaps, been demanded by his relatives, and to which,
according to the
custom of the time, he would have been entitled as
Burgomaster. The
refusal to sanction the interment aroused, more especially in the
Catholic
world, a painful sensation.”
A brass memorial plate hung in the Cathedral at Zeitz had already
disappeared in 1686, nor have the cities of his birth or residence ever
shown
any appreciation of this man, whose work more deserves their
gratitude
than does that of the multitude of soldiers whose monuments
decorate every
village and city square. It is true that in 1822 a marble tablet was
placed behind the altar in
the Church of St. Jacob in Chemnitz, but even
this was removed to the Historical Museum
later on.
He left a modest estate, which was the subject of considerable litigation by
his descendants, due to the mismanagement of the guardian. Hofmann has
succeeded in tracing the descendants for two generations,
down to 1609, but
the line is finally lost among the multitude of other
Agricolas.
To deduce Georgius Agricola's character we need not search beyond the
discovery of his steadfast adherence to the religion of his fathers
amid the
bitter storm of Protestantism around him, and need but to
remember at the
same time that for twenty-five years he was entrusted
with elective positions
of an increasingly important character in this
same community. No man
could have thus held the respect of his countrymen unless he were
devoid of
bigotry and possessed of the highest sense of integrity,
justice, humanity,
and patriotism.
AGRICOLA'S INTELLECTUAL ATTAINMENTS AND
POSITION IN SCIENCE.
Agricola's education was the most thorough that his times afforded in
the classics, philosophy, medicine, and sciences generally. Further, his writings
disclose a most exhaustive knowledge not only of
an extraordinary range of
classical literature, but also of obscure
manuscripts buried in the public libraries
of Europe. That his general learning was held to be of a high order is amply
evidenced from the correspondence of the other scholars of his
time—Erasmus,
Melanchthon, Meurer, Fabricius, and others.
Our more immediate concern, however, is with the advances which were due
to him in the sciences of Geology, Mineralogy, and Mining Engineering. No
appreciation of these attainments can be conveyed to the reader
unless he
has some understanding of the dearth of knowledge in these
sciences prior
to Agricola's time. We have in Appendix B given a brief review of the
literature extant at
this period on these subjects. Furthermore, no appreciation
of Agricola's contribution to science can
be gained without a study of
Ortu et
Causís
more general interest, it contains but incidental reference to
Geology and
Mineralogy. Apart from the book of Genesis, the only attempts at funda
mental
explanation of natural phenomena were those of the Greek Philosophers
and the Alchemists. Orthodox beliefs Agricola scarcely mentions; with the
Alchemists he had
no patience. There can be no doubt, however, that his
views are greatly coloured by
his deep classical learning. He was in fine to a
certain distance a follower of Aristotle,
Theophrastus, Strato, and other leaders
of the Peripatetic school. For that matter, except for the muddy current
which the alchemists had
introduced into this already troubled stream,
the whole thought of the
learned world still flowed from the Greeks. Had he
not, however, radically departed from the teachings of the
Peripatetic school,
his work would have been no contribution to the
development of science. Certain of their teachings he repudiated with great vigour, and his
laboured and detailed arguments in their refutation form the first
battle in
science over the results of observation To use
his own words: “Those things which we see with our eyes and
understand
by means of our senses are more clearly to be demonstrated
than if learned
by means of reasoning.”
tated as much care and detail in refutation of such
deep-rooted beliefs, as would
be demanded to-day by an attempt at a
refutation of the theory of evolution,
and in consequence his works are
often but dry reading to any but those
interested in the development of
fundamental scientific theory.
In giving an appreciation of Agricola's views here and throughout the
footnotes, we do not wish to convey to the reader that he was in all
things
free from error and from the spirit of his times, or that his
theories, constructed
long before the atomic theory, are of the
clear-cut order which that
basic hypothesis has rendered possible to
later scientific speculation in these
branches. His statements are sometimes much confused, but we reiterate that
and of most of his successors for over
two hundred years. As an indication of
his grasp of some of the wider aspects of geological
phenomena we reproduce,
in Appendix A, a passage from
first adequate declaration of the part
played by erosion in mountain sculpture. But of all of Agricola's theoretical views those are of the greatest interest
which
relate to the origin of ore deposits, for in these matters he had
the greatest
opportunities of observation and the most experience. We have on page 108
reproduced and discussed his theory at considerable
length, but we may repeat
here, that in his propositions as to the
circulation of ground waters, that ore
channels are a subsequent
creation to the contained rocks, and that they
were filled by
deposition from circulating solutions, he enunciated the
founda
tions of our modern theory, and in so doing took a step in
advance greater than
that of any single subsequent authority. In his contention that ore channels
were created by erosion of
subterranean waters he was wrong, except for
special cases, and it was
not until two centuries later that a further step in
advance was taken
by the recognition by Van Oppel of the part played by
fissuring in
these phenomena. Nor was it until about the same time that the
filling of ore channels in
the main by deposition from solutions was generally
accepted. While Werner, two hundred and fifty years after Agricola, is
generally
revered as the inspirer of the modern theory by those whose reading
has
taken them no farther back, we have no hesitation in asserting that of the
propositions of each author, Agricola's were very much more nearly in
accord with modern views. Moreover, the main result of the new ideas
brought forward by Werner was
to stop the march of progress for half a
century, instead of speeding
it forward as did those of Agricola.
In mineralogy Agricola made the first attempt at systematic treatment
of
the subject. His system could not be otherwise than wrongly based,
as he could
scarcely see forward two or three centuries to the atomic theory
and
our vast fund of chemical knowledge. However, based as it is upon
such properties as solubility and
homogeneity, and upon external character
istics such as colour,
hardness, &c., it makes a most creditable advance
upon
Theophrastus, Dioscorides, and Albertus Magnus—his only predecessors.
He is the first to assert that bismuth and antimony are true primary metals;
and to some sixty actual mineral species described previous to his time
he
added some twenty more, and laments that there are scores
unnamed.
As to Agricola's contribution to the sciences of mining and
metal
lurgy, While he describes, for the first
time, scores of methods and processes,
no one would contend that they
were discoveries or inventions of his
own. They represent the accumulation
of generations of experience and
knowledge; but by him they were, for the
first time, to receive
detailed and intelligent exposition. Until Schlüter's
work nearly two centuries later, it was not
excelled. There is no measure by
which we may gauge the value of such a work to
the men who followed in
this profession during centuries, nor the
benefits enjoyed by humanity
through them.
That Agricola occupied a very considerable place in the great awakening of
learning will be disputed by none except by those who place the
development
of science in rank far below religion, politics,
literature, and art. Of wider
importance than the details of his achievements in the mere
confines of the
particular science to which he applied himself, is the
fact that he was the first
to found any of the natural sciences upon
research and observation, as opposed
to previous fruitless speculation. The wider interest of the members of the
medical profession in the
development of their science than that of geologists
in theirs, has led
to the aggrandizement of Paracelsus, a contem
porary of Agricola,
as the first in deductive science. Yet no comparative
study of the unparalleled egotistical ravings of this
half-genius, half-alchemist,
with the modest sober logic and real
research and observation of Agricola,
can leave a moment's doubt as to
the incomparably greater position which
should be attributed to the
latter as the pioneer in building the foundation
of science by
deduction from observed phenomena. Science is the base upon
which is reared the civilization of to-day, and
while we give daily credit to all
those who toil in the superstructure,
let none forget those men who laid its
first foundation stones. One of the greatest of these was Georgius Agricola.
Agricola seems to have been engaged in the preparation of
Metallica
letter
from Petrus Plateanus, a schoolmaster at Joachimsthal, to the great
humanist, Erasmus,
will be still
more indebted to Agricola when he brings to light the books
of
publish twelve books That the appearance of this
work was eagerly anticipated is evidenced by
a letter from George Fabricius
to Valentine Hertel:
are
being awaited. If he treats the material at hand with his usual zeal,
he will win for
himself glory such as no one in any of the fields of literature
has
attained for the last thousand years.” According to the dedication of
its early publication. The work was apparently finished in 1550, for the
dedication to the
Dukes Maurice and August of Saxony is dated in December of
that year. The eulogistic poem by his friend, George Fabricius, is dated in
1551.
The publication was apparently long delayed by the preparation of the
woodcuts; and, according to Mathesius,
prepared by Basilius
Wefring. In the preface of
does not mention who prepared the
sketches, but does say: “I have hired
illustrators to delineate
their forms, lest descriptions which are conveyed
by words should
either not be understood by men of our own times, or
should cause
difficulty to posterity.” In 1553 the completed book was
sent to
Froben for publication, for a letter
March, 1553, announces its dispatch to
the printer. An interesting letter
from the
Elector Augustus to Agricola, dated January 18, 1555, reads:
“Most learned, dear and faithful subject, whereas you have sent
to the Press
a Latin book of which the title is said to be
been praised to us and we should like to know the contents,
it is our gracious
command that you should get the book translated when
you have the
opportunity into German, and not let it be copied more
than once or be
printed, but keep it by you and send us a copy. If you should need a
writer for this purpose, we will provide one. Thus you will fulfil our
gracious behest.” The German translation
was prepared by Philip Bechius,
a Basel University Professor of
Medicine and Philosophy. It is a wretched
work, by one who knew nothing of the science, and who
more especially had no
appreciation of the peculiar Latin terms coined
by Agricola, most of which
he rendered literally.
It is a sad commentary on his countrymen that no
correct German
translation exists. The Italian translation is by Michelangelo
Florio, and is by him
dedicated to Elizabeth, Queen of England. The title
page of the first edition is reproduced later on, and the full
titles of other
editions are given in the Appendix, together with the
author's other works. The following are the short titles of the various editions of
together
with the name and place of the publisher:—
LATIN EDITIONS.
In addition to these, Leupold,
edition, without illustrations, Schweinfurt, 1607. We have not
been able to
find a copy of this edition, and are not certain of its
existence. The same
catalogues also mention an octavo edition of
1612 or 1614, with notes by Joanne Sigfrido; but we believe this to be
a
confusion with Agricola's subsidiary works, which were published at
this
time and place, with such notes.
GERMAN EDITIONS.
There are other editions than these, mentioned by bibliographers, but we
have been unable to confirm them in any library. The most reliable
of such bibliographies, that of John Ferguson,
above;
ITALIAN EDITION.
OTHER LANGUAGES.
So far as we know,
than Latin,
German, and Italian. However, a portion of the accounts of
the firm of Froben were published
in 1881
March, 1560, of a sum to one Leodigaris Grymaldo for some other
work, and
also for “correction of Agricola's
of course, be an error for the Italian edition, which appeared a
little later. There is also mention
An interesting note appears in
the glossary given by Sir John Pettus in
his translation of Lazarus Erckern's
work on assaying. He says
any more words, because the printer calls for what
I did write of a metallick
dictionary, after I first proposed the
printing of Erckern, but intending
within the compass of a year to
publish Georgius Agricola,
(being fully translated) in English, and also to
add a dictionary to it, I
shall reserve my remaining essays (if what I
have done hitherto be approved)
till then, and so I proceed in the
dictionary.” The translation was never
published and extensive
inquiry in various libraries and among the family
of Pettus has failed
to yield any trace of the manuscript.
GEORGII AGRICOLAE
DE RE METALLICA LIBRI XII<28> QVI-
bus Officia, Inſtrumenta, Machinæ, acomnia denique ad
Metalli
tam ſpectantia, non modo
luculentiſſimè deſcribuntur, ſed & per
effigies, ſuis locis inſertas, adiunctis Latinis,
Germanicis〈qué〉 appel
lationibus ita ob oculos ponuntur, ut
clarius tradi non poſſint.
BIVSDEM
DE ANIMANTIBVS SVBTERRANEIS Liber, ab Autore re
cognitus:cum
Indicibus diuerſis, quicquid in opere tractatum eſt,
pulchrè demonſtrantibus.
BASILEAE M<28> D<28> LVI<28>
Cum Priuilegio Imperatoris in annos v.
& Galliarum Regis ad Sexennium.
GEORGIVS FABRICIVS IN LI-
bros Metallicos GEORGII AGRICOL AE phi
loſophi
præſtantiſſimi.
AD LECTOREM.
Siiuuat ignita cognoſcere fronte Chimæram,
Semicanem
nympham, ſemibouem〈qué〉 uirum:
Sicentum capitum Titanem, tot〈qué〉 ferentem
Sublimem manibus tela
cruenta Gygen:
Siiuuat Ætneum penetrare Cyclopis in antrum,
Atque alios, Vates
quos peperere, metus:
Nunc placeat mecum doctos euoluere libros,
Ingenium AGRICOLAE quos dedit
acre tibi.
Non hic uana tenet ſuſpenſam fabula mentem:
Sed
precium, utilitas multa, legentis erit.
Quidquid terra ſinu, gremio〈qué〉 recondiditimo,
Omne tibi
multis eruit ante libris:
Siue fluens ſuperas ultro nitatur in oras,
Inueniat facilem
ſeu magis arte uiam.
Perpetui proprns manant de fontibus amnes,
Eſt grauis
Albuneæ ſponte Mephitis odor.
Lethales ſunt ſponte ſcrobes Dicæarchidis oræ,
Et micat è media conditus ignis humo.
Plana Nariſcorum cùm tellus arſitin agro,
Ter curua
nondum falce reſecta Ceres.
Nec dedit hoc damnum paſtor, riec Iuppiterigne:
Vulcani per
ſeruperat ira ſolum.
Terrifico aura foras erumpens, incita motu,
Sæpefacit montes,
antè ubi plana uia eſt.
Hæcabſtruſa cauis, imo〈qué〉 incognita fundo,
Cognita natura ſæpe fuere duce.
Arte hominum, in lucem ueniunt quoque multa, manu〈qué〉
Terræ
multiplices effodiuntur opes.
Lydia ſicnitrum profert, Islandia ſulfur,
Acmodò
Tyrrhenus mittit alumen ager.
Succina, quâ trifi do ſubit æquor Viſtula cornu,
Piſcantur Codano corpora ſerua ſinu.
Quid memorem regum precioſa inſignia gemmas,
Marmora〈qué〉 excelſis ſtructa ſub aſtra
iugis?
Nil lapides, nil ſaxa moror: ſunt pulchra metalia,
Crœfetuis opibus clara, Myda〈qué〉 tuis,
Quæ〈qué〉 acer Macedo terra Creneide fodit,
Nomine permutans
nomina priſca ſuo.
Atnuncnon ullis cedit GERMANIA terris,
Hic auri in uenis locupletibus aura refulget,
Non alio
meſſis carior ulla loco.
Auricomum extulerit felix Campania ramum,
Nec fructu nobis
deſiciente cadit.
Eruit argenti ſolidas hoc tempore maſſas
Foſſor, dc proprijs arma〈qué〉 miles agris.
Ignotum Graijs eſt Heſperijs〈qué〉 metallum,
Quod
Biſemutum lingua paterna uocat.
Candidius nigro, ſed plumbo nigrius albo,
Noſtra quoque hoc
uena diuite fundit humus.
Funditur in tormenta, corus cum imitantia fulmen,
Æs, in〈qué〉
hoſtiles ferrea maſſa domos.
Scribuntur plumbo libri: quis credidit antè
Quàm mirandam
artem Teutonis ora dedit?
Nec tamen hoc alijs, aut illa petuntur ab oris,
Eruta Germano cuncta
metalla ſolo.
Sed quid ego hæc repeto, monumentis tradita claris
AGRICOLAE,
quæ nunc docta per ora uolant?
Hic cauſſis ortus, & formas uiribus addit,
Et
quærenda quibus ſint meliora locis.
Quæ ſi mente prius legiſti candidus æqua:
Da
reliquis quoque nunc tempora pauca libris.
Vtilitas ſequitur cultorem: crede, uoluptas
Non iucunda minor,
rara legentis, erit.
Iudicio〈qué〉 prius ne quis malè damnet iniquo,
Quæ
ſunt auctoris munera mira Dei:
Eripit ipſe ſuis primùm tela hoſtibus, in〈qué〉
Mittentis torquet ſpicula rapta caput.
Fertur equo latro, uehitur pirata triremi:
Ergo necandus equus, nec
fabricanda ratis?
Viſceribus terræ lateant abſtruſa metalla,
Vti
opibus neſcit quòd mala turba ſuis?
Quiſquis es, aut doctis pareto monentïbus, aut te
Inter
habere bonos ne fateare locum.
Se non in prærupta metallicus abijcit audax,
Vt quondam
immiſſo Curtius acer equo:
Sed prius ediſcit, quæ ſunt noſcenda perito,
Quod〈qué〉 facit, multa doctus ab arte facit.
Vt〈qué〉 gubernator ſeruat cum ſidere uentos:
Sic
minimè dubijs utitur ille notis.
Iaſides nauim, currus regit arte Metiſcus:
Foſſor opus peragit nec minus arte ſuum.
Indagat uenæ ſpacium, numerum〈qué〉, modum〈qué〉,
Siue obliqua ſuum, rectaúe tendatiter.
Paſtor ut explorat quæ terra ſit apta colenti,
Quæ bene lanigeras, quæ malè paſcat oucs.
En terræ intentus, quid uincula linea tendit?
Fungitur officio iam Ptolemæe tuo.
Vt〈qué〉 ſuæ inuenit menſuram iura〈qué〉
uenæ,
In uarios operas diuidit ind e uiros.
Iam〈qué〉 aggreſſus opus, uiden' ut mouet omne quod
obſtat,
Aſſidua ut uerſat ſtrenuus arma
manu?
Ne tibi ſurdeſcant ferri tinnitibus aures,
Ad grauiora ideo
conſpicienda ueni.
Inſtruit ecce ſuis nunc artibus ille minores:
Sedulitas
nulli non operoſa loco.
Metiri docet hic uenæ ſpacium〈qué〉 modum〈qué〉,
Vt〈qué〉 regat poſitis ſinibus arua lapis,
Ne quis transmiſſo uiolentus limite pergens,
Non ſibi
conceſſas, in ſua uertat, opes.
Hic docet inſtrumenta, quibus Piutonia regna
Tutus adit,
ſaxi permeat atque uias.
Quanta (uides) ſolidas expugnet machina terras:
Machina non ullo
tempore uiſa prius.
Cede nouis, nulla non inclyta laude uetuſtas,
Poſteritas
meritis eſt quoque grata tuis.
Tum quia Germano ſunt hæc inuenta ſub axe,
Si quis es,
inuidiæ contrahe uela tuæ.
Auſonis ora tumct bellis, terra Attica cultu,
Germanum
inſractus tollit ad aſtra labor.
Nec tamen ingenio ſolet infeliciter uti,
Mite gerát
Phœbi, ſeu graue Martis opus.
Tempus adeſt, ſtructis uenarum montibus, igne
Explorare,
uſum quem ſibi uena ferat.
Non labor ingenio caret hic, non copia fructu,
Eſt adaperta
bonæ prima feneſtra ſpei.
Ergo inſtat porrò grauiores ferre labores,
Intentas operi
nec remouere manus.
Vrere ſiue locus poſcat, ſeu tundere uenas,
Siue
lauare lacu præter euntis aquæ.
Seu flammis iterum modicis torrere neceſſe eſt,
Excoquere aut faſtis ignibus omne malum,
Cùm fluit æs riuis, auri argenti〈qué〉 metallum,
Spes
animo foſſor uix capit ipſe ſuas.
Argentum cupidus fuluo ſecernit ab auro,
Et plumbi lentam demit
utrique moram.
Separat argentum, lucri ſtudioſus, ab ære,
Seruatis,
linquens deteriora, bonis.
Quæ ſi cuncta uelim tenui percurrere uerſu,
Ante alium
reuehat Memnonis o
Poſtremus labor eſt, concretos diſcereſuccos,
Quos fert innumeris Teutona terra locis.
Quo ſal, quo nitrum, quo pacto fiat alumen,
Vſibus
artiſicis cùm parat illa manus:
Necnon chalcantum, ſulfur, fluidumque bitumen,
Maſſa〈qué〉 quo uitri lenta dolanda modo.
Suſcipit hæc hominum mirandos cura labores,
Pauperiem
uſqueadeo ferre famem〈qué〉 graue eſt,
Tantus amor uictum paruis extundere natis,
Et patriæ ciuem non
dare uelle malum.
Nec manet in terræ foſſoris merſa latebris
Mens,
ſed fert domino uota preces〈qué〉 Deo.
Munificæ expectat, ſpe plenus, munera dextræ,
Extollens animum lætus ad aſtra ſuum.
Diuitias CHRISTVS dat noticiam〈qué〉 fruendi,
Cui memori grates
pectore ſemper agit.
Hoc quoque laudati quondam fecere Philippi,
Qui uirtutis habent cum
pietate decus.
Huc oculos, huc flecte animum, ſuauiſſime Lector,
Auctorem〈qué〉 pia noſcito mente Deum.
AGRICOLAE hinc optans operoſo fauſta labori,
Laudibus eximij
candidus eſto uiri.
Ille ſuum extollit patriæ cum nomine nomen,
Et uir in ore
frequens poſteritatis erit.
Cuncta cadunt letho, ſtudij monumenta uigebunt,
Purpurei
doneclumina ſolis erunt.
Miſenæ M. D. LI.
èludo illuſtri.
For completeness' sake we reproduce in the original Latin the laudation of
Agricola
by his friend, Georgius Fabricius, a leading scholar of his
time. It has but little intrinsic
value for it is not poetry of a very high
order, and to make it acceptable English would require
certain
improvements, for which only poets have license. A “free” translation of the last
few lines indicates its
complimentary character:—
“He doth raise his country's fame with his own
And in the mouths
of nations yet unborn
His praises shall be sung; Death comes to all
But great achievements raise a monument
Which shall endure until
the sun grows cold.”
TO THE MOST ILLUSTRIOUS
AND MOST MIGHTY DUKES OF
Saxony, Landgraves
of Thuringia, Margraves of Meissen,
Imperial Overlords of Saxony,
Burgraves of Altenberg
and Magdeburg, Counts of Brena, Lords of
Pleissnerland, To MAURICE Grand Marshall
and Elector of the Holy
Roman Empire
and to his brother AUGUSTUS,
GEORGE AGRICOLA S. D.
Most illustrious Princes, often have I considered
the metallic arts as a
whole, as Moderatus Columella
considered the agricultural arts, just as if I
had been
considering the whole of the human
body; and when I had perceived the
various parts
of the subject, like so many members of the body,
I
became afraid that I might die before I should
understand its full
extent, much less before I
could immortalise it in writing. This book
itself indicates the length and breadth of the subject, and
the number
and importance of the sciences of which at least some little
knowledge
is necessary to miners. Indeed, the subject of mining is a very exten
sive one, and one very
difficult to explain; no part of it is fully dealt
with by the Greek
and Latin authors whose works survive; and since
the art is one of the
most ancient, the most necessary and the most profitable
to mankind, I
considered that I ought not to neglect it. Without doubt,
none of the arts is older than agriculture, but that of
the metals is not
less ancient; in fact they are at least equal and
coeval, for no mortal man ever
tilled a field without implements. In truth, in all the works of agricul
ture, as in the other arts,
implements are used which are made from metals,
or which could not be
made without the use of metals; for this reason
the metals are of the
greatest necessity to man. When an art is so poor that
it lacks metals, it is not of much
importance, for nothing is made without
tools. Besides, of all ways whereby great wealth is acquired by good and
honest
means, none is more advantageous than mining; for although from
fields
which are well tilled (not to mention other things) we derive rich yields,
yet we obtain richer products from mines; in fact, one mine is often
much
more beneficial to us than many fields. For this reason we learn from the
history of nearly all ages that very
many men have been made rich by the
by. But I will not now speak more of these matters, because I have
dealt
with these subjects partly in the first book of this work, and partly in
the other work entitled
the
charges which have been made against metals and against miners. Now, though the art of husbandry, which I willingly rank with the art of
mining, appears to be divided into many branches, yet it is not
separated
into so many as this art of ours, nor can I teach the
principles of this as
easily as Columella did of that. He had at hand many writers upon hus
bandry whom he could
follow,—in fact, there are more than fifty Greek
authors whom
Marcus Varro enumerates, and more than ten Latin ones,
whom Columella
himself mentions. I have only one whom I can follow;
that is C. Plinius Secundus,
digging ores and of making metals. Far from the whole of the art having
been treated by any one writer,
those who have written occasionally on any
one or another of its
branches have not even dealt completely with a single
one of them. Moreover, there is a great scarcity even of these, since alone of
all
the Greeks, Strato of Lampsacus,
a book on the subject,
poet Philo, a small part of which embraced to some degree the
occupation
of mining.
was similar
in title, miners as slaves or as persons condemned to serve in the
mines. Of the Latin writers, Pliny, as I have already said, has described
a few
methods of working. Also among the authors I must include the modern
writers, whosoever they
are, for no one should escape just condemnation
who fails to award due
recognition to persons whose writings he uses, even
very slightly. Two books have been written in our tongue; the one on the
assaying of
mineral substances and metals, somewhat confused, whose author
is
unknown
said to have written, although the German book
was written by Calbus of
Freiberg, a well-known doctor; but neither of
them accomplished the task
experienced in many matters, wrote
in vernacular Italian on the
subject of the melting, separating, and
alloying of metals.
touched briefly on the methods of smelting certain ores, and explained
more fully the methods of making certain juices; by reading his
directions, I have refreshed my memory of those things which I myself
saw in Italy; as for many matters on which I write, he did not touch
upon
them at all, or touched but lightly. This book was given me by Franciscus
Badoarius, a Patrician of Venice,
and a man of wisdom and of repute; this
he had promised that he would
do, when in the previous year he was at
Marienberg, having been sent by
the Venetians as an Ambassador to King
Ferdinand. Beyond these books I do not find any writings on the metallic
arts. For that reason, even if the book of Strato existed, from all these
sources not one-half of the whole body of the science of mining could
be
pieced together.
Seeing that there have been so few who have written on the subject of the
metals, it appears to me all the more wonderful that so many alchemists
have
arisen who would compound metals artificially, and who would
change one
into another. Hermolaus Barbarus,
distinguished in all kinds of learning, has
mentioned the names of many in
his writings; and I will proffer more,
but only famous ones, for I will limit myself
to a few. Thus Osthanes has written on
Chanes; Zosimus, the Alexandrian, to his sister
Theosebia; Olympiodorus,
also an Alexandrian; Agathodæmon;
Democritus, not the one of Abdera,
but some other whom I know not; Orus
Chrysorichites, Pebichius, Comerius,
Joannes, Apulejus, Petasius,
Pelagius, Africanus, Theophilus, Synesius,
Stephanus to Heracleus
Cæsar, Heliodorus to Theodosius, Geber, Callides
Rachaidibus,
Veradianus, Rodianus, Canides, Merlin, Raymond Lully,
Arnold de Villa
Nova, and Augustinus Pantheus of Venice; and three women,
Cleopatra,
the maiden Taphnutia, and Maria the Jewess.
employ obscure language, and
Johanes Aurelius Augurellus of Rimini,
alone has used the language of
poetry. There are many other books on
things use strange names, which do not properly belong to the metals,
and
because some of them employ now one name and now another, invented
by
themselves, though the thing itself changes not. These masters teach their
disciples that the base metals, when smelted,
are broken up; also they teach
the methods by which they reduce them to
the primary parts and
remove whatever is superfluous in them, and by
supplying what is
wanted make out of them the precious
metals—that is, gold and silver,—
all of which they carry
out in a crucible. Whether they can do these things
or not I cannot decide; but, seeing
that so many writers assure us with all
earnestness that they have
reached that goal for which they aimed, it would
seem that faith might
be placed in them; yet also seeing that we do not
read of any of them
ever having become rich by this art, nor do we now see
them growing
rich, although so many nations everywhere have produced, and
are
producing, alchemists, and all of them are straining every nerve night and
day to the end that they may heap a great quantity of gold and silver,
I should
say the matter is dubious. But although it may be due to the carelessness
of the writers that they
have not transmitted to us the names of the masters
who acquired great
wealth through this occupation, certainly it is clear that
their
disciples either do not understand their precepts or, if they do
under
stand them, do not follow them; for if they do comprehend
them, seeing that
these disciples have been and are so numerous, they
would have by to-day filled Even their books proclaim their vanity, for
they inscribe in them the
names of Plato and Aristotle and other philosophers,
in order that such
high-sounding inscriptions may impose upon simple people
and pass for
learning. There is another class of alchemists who do not
change the substance of
base metals, but colour them to represent gold or silver,
so that they
appear to be that which they are not, and when this appearance
is taken
from them by the fire, as if it were a garment foreign to them, they
return to their own character. These alchemists, since they deceive people,
are not only held in the
greatest odium, but their frauds are a capital offence. No less a fraud, warranting capital punishment, is committed by a third sort
of alchemists; these throw into a crucible a small piece of gold or
silver
hidden in a coal, and after mixing therewith fluxes which have
the power of
extracting it, pretend to be making gold from orpiment, or
silver from tin and
like substances. But concerning the art of alchemy, if it be an art, I will
speak further
elsewhere. I will now return to the art of mining.
Since no authors have written of this art in its entirety, and since
foreign nations and races do not understand our tongue, and, if they
did
understand it, would be able to learn only a small part of the art
through the
works of those authors whom we do possess, I have written
these twelve books Of these, the first book contains the arguments which may
be used
against this art, and against metals and the mines, and what can be
said in their favour. The second book describes the miner, and branches into
The third book deals with veins and
stringers, and seams in the rocks. The fourth book explains the method of
delimiting veins, and also
describes the functions of the mining officials. The fifth book describes the digging of ore and the surveyor's art.
The
sixth book describes the miners' tools and machines. The seventh book is
on the assaying of ore. The eighth book lays down the rules for the work of
roasting, crushing,
and washing the ore. The ninth book explains the
methods of smelting ores. The tenth book instructs those who are studious
of the metallic arts in
the work of separating silver from gold, and lead from
gold and silver. The eleventh book shows the way of separating silver from
copper. The twelfth book gives us rules for manufacturing salt, soda, alum,
vitriol, sulphur, bitumen, and glass.
Although I have not fulfilled the task which I have undertaken, on account
of the great magnitude of the subject, I have, at all events,
endeavoured to fulfil
it, for I have devoted much labour and care, and
have even gone to some
expense upon it; for with regard to the veins,
tools, vessels, sluices, machines,
and furnaces, I have not only
described them, but have also hired illustrators
to delineate their
forms, lest descriptions which are conveyed by words
should either not
be understood by men of our own times, or should cause
difficulty to
posterity, in the same way as to us difficulty is often caused by
many
names which the Ancients (because such words were familiar to all of
them) have handed down to us without any explanation.
I have omitted all those things which I have not myself seen, or have
That which I have
neither seen, nor carefully considered after reading
or hearing of, I have not
written about. The same rule must be understood with regard to all my in
struction,
whether I enjoin things which ought to be done, or describe things
which are usual, or condemn things which are done. Since the art of mining
does not lend itself to elegant language, these
books of mine are correspond
ingly lacking in refinement of style. The things dealt with in this art of
metals sometimes lack names, either
because they are new, or because, even
if they are old, the record of
the names by which they were formerly known
has been lost. For this reason I have been forced by a necessity, for which I
must be
pardoned, to describe some of them by a number of words combined,
and
to distinguish others by new names,—to which latter class belong
Discretor, Lotor,
names, such as the
the name of a two-wheeled
vehicle, but I have adopted it for a small vehicle
which has only one
wheel; and if anyone does not approve of these names,
let him either
find more appropriate ones for these things, or discover the
words used
in the writings of the Ancients.
These books, most illustrious Princes, are dedicated to you for many
reasons, and, above all others, because metals have proved of the
greatest
value to you; for though your ancestors drew rich profits from
the revenues
of their vast and wealthy territories, and likewise from
the taxes which were
paid by the foreigners by way of toll and by the
natives by way of tithes, yet
they drew far richer profits from the
mines. Because of the mines not a few
towns have risen into eminence, such as
Freiberg, Annaberg, Marienberg,
Schneeberg, Geyer, and Altenberg, not
to mention others. Nay, if I under
stand anything, greater wealth now lies hidden
beneath the ground in the
mountainous parts of your territory than is
visible and apparent above
ground. Farewell.
Many persons hold the opinion that the metal indus
tries are
fortuitous and that the occupation is one
of sordid toil, and
altogether a kind of business
requiring not so much skill as labour. But as for
myself, when I reflect carefully upon its special
points
one by one, it appears to be far otherwise. For a miner must have the greatest skill in his
work, that he may know
first of all what mountain
or hill, what valley or plain, can be
prospected most
profitably, or what he should leave alone; moreover, he
must understand the
veins, stringersThen he must be thoroughly
familiar with the many and varied species of
earths, juices
stones,
marbles, rocks, metals, and compoundsHe must also have a
Lastly, there are the
various systems of assaying
preparing them for smelting; and here again there
are many altogether
diverse methods. For there is one method for gold and silver, another
for copper,
another for quicksilver, another for iron, another for lead, andAlthough the
evaporation of juices is an art apparently quite distinct
from metallurgy,
yet they ought not to be considered separately,
inasmuch as these juices
are also often dug out of the ground
solidified, or they are produced from
certain kinds of earth and stones
which the miners dig up, and some of the
juices are not themselves
devoid of metals. Again, their treatment is not
simple, since there is one method for
common salt, another for soda
another for alum, another for vitriol
for bitumen.
Furthermore, there are many arts and sciences of which a miner should
not be ignorant. First there is Philosophy, that he may discern the origin,
cause, and
nature of subterranean things; for then he will be able to dig
out the
veins easily and advantageously, and to obtain more abundant results
from his mining. Secondly, there is Medicine, that he may be able to look
after his
diggers and other workmen, that they do not meet with those
or if they do meet with them, that he himself may be
able to heal them or
may see that the doctors do so. Thirdly follows Astronomy, that he may
know the divisions of the heavens
and from them judge the direction of
the veins. Fourthly, there is the science of Surveying that he may be able
to
estimate how deep a shaft should be sunk to reach the tunnel which is
being driven to it, and to determine the limits and boundaries in these
workings, especially in depth. Fifthly, his knowledge of Arithmetical Science
should be such that he
may calculate the cost to be incurred in the
machinery and the working
of the mine. Sixthly, his learning must comprise
Architecture, that he himself may
construct the various machines and timber
work required underground, or
that he may be able to explain the method
of the construction to
others. Next, he must have knowledge of Drawing,
that he can draw plans of his
machinery. Lastly, there is the Law, especially
that dealing with metals, that he
may claim his own rights, that he may
undertake the duty of giving
others his opinion on legal matters, that he
may not take another man's
property and so make trouble for himself, and
that he may fulfil his
obligations to others according to the law.
It is therefore necessary that those who take an interest in the methods
and precepts of mining and metallurgy should read these and others of
our
books studiously and diligently; or on every point they should
consult
expert mining people, though they will discover few who are
skilled in the
whole art. As a rule one man understands only the methods of mining,
another
possesses the knowledge of washing
art of smelting, another has a knowledge
of measuring the hidden parts of
the earth, another is skilful in the
art of making machines, and finally,
another is learned in mining law. But as for us, though we may not have
perfected the whole art of the
discovery and preparation of metals, at least
we can be of great
assistance to persons studious in its acquisition.
But let us now approach the subject we have undertaken.
Since there
has always been the greatest disagreement amongst men
concerning metals
and mining, some praising, others utterly condemning
them, therefore I have
decided that before imparting my instruction, I
should carefully weigh
the facts with a view to discovering the truth
in this matter.
So I may begin with the question of utility, which is a two-fold one,
for either it may be asked whether the art of mining is really
profitable or
not to those who are engaged in it, or whether it is
useful or not to the rest
of mankind. Those who think mining of no advantage to the men who follow
the
occupation assert, first, that scarcely one in a hundred who dig metals or
other such things derive profit therefrom; and again, that miners,
because they
entrust their certain and well-established wealth to
dubious and slippery
fortune, generally deceive themselves, and as a
result, impoverished by
lives. But persons who hold these views do not perceive how much a learned
and
experienced miner differs from one ignorant and unskilled in the art.
The latter digs out the ore without any careful discrimination, while the
former first assays and proves it, and when he finds the veins either
too
narrow and hard, or too wide and soft, he infers therefrom that
these cannot
be mined profitably, and so works only the approved ones. What wonder
then if we find the incompetent miner suffers loss, while
the competent one
is rewarded by an abundant return from his mining? The same thing
applies to husbandmen. For those who cultivate land which is alike arid,
heavy, and barren, and
in which they sow seeds, do not make so great a
harvest as those who
cultivate a fertile and mellow soil and sow their grain
in that. And since by far the greater number of miners are unskilled rather
than
skilled in the art, it follows that mining is a profitable occupation to
very few men, and a source of loss to many more. Therefore the mass of
miners who are quite unskilled and ignorant in the
knowledge of veins not
infrequently lose both time and troubleSuch men are accustomed for the
most part to take to mining, either when
through being weighted with the
fetters of large and heavy debts, they
have abandoned a business, or desiring to
change their occupation, have
left the reaping-hook and plough; and so
if at any time such a man
discovers rich veins or other abounding mining
produce, this occurs
more by good luck than through any knowledge on his
part. We learn from history that mining has brought wealth to many, for
from
old writings it is well known that prosperous Republics, not a few kings,
and many private persons, have made fortunes through mines and their
produce. This subject, by the use of many clear and illustrious examples, I
have
dilated upon and explained in the first Book of my work entitled
“
Veteribus et Novis
Metallis,
profitable to those who give it care and attention.
Again, those who condemn the mining industry say that it is not in the
least stable, and they glorify agriculture beyond measure. But I do not see
how they can say this with truth, for the silver-mines
at Freiberg in Meissen
remain still unexhausted after 400 years, and
the lead mines of Goslar after 600
years. The proof of this can be found in the monuments of history.
The
gold and silver mines belonging to the communities of Schemnitz and
Cremnitz have been worked for 800 years, and these latter are said to
be
the most ancient privileges of the inhabitants. Some then say the profit
from an individual mine is unstable, as if
forsooth, the miner is, or ought to
be dependent on only one mine, and
as if many men do not bear in common
their expenses in mining, or as if
one experienced in his art does not dig
another vein, if fortune does
not amply respond to his prayers in the first
case. The New Schönberg at Freiberg has remained stable beyond the
memory
of man
It is not my intention to detract anything from the dignity of
agri
culture, and that the profits of mining are less stable I will
always and readly
admit, for the veins do in time cease to yield
metals, whereas the fields bring
lorth fruits every year. But though the business of mining may be loss
reliable it is more
productive, so that in reckoning up, what is wanting in
stability is
found to be made up by productiveness. Indeed, the yearly
profit of a lead mine in comparison with the
fruitfulness of the best fields,
is three times or at least twice as
great. How much does the profit from
gold or silver mines exceed that earned
from agriculture? Wherefore truly
and shrewdly does Xenophon
“There is
land of such a nature that if you sow, it does not yield crops,
but if
you dig, it nourishes many more than if it had borne fruit.” So let
the farmers have for themselves the fruitful fields and cultivate the
fertile
hills for the sake of their produce; but let them leave to
miners the gloomy
valleys and sterile mountains, that they may draw
forth from these, gens
and metals which can buy, not only the crops,
but all things that are sold.
The critics say further that mining is a perilous occupation to pursue,
because the miners are sometimes killed by the pestilential air which
they
breathe; sometimes their lungs rot away; sometimes the men perish
by being
crushed in masses of rock; sometimes, falling from the ladders
into the
shafts, they break their arms, legs, or necks; and it is added
there is no com
pensation which should be thought great enough to
equalize the extreme
dangers to safety and life. These occurrences, I confess, are of exceeding
gravity, and moreover,
fraught with terror and peril, so that I should con
sider that the
metals should not be dug up at all, if such things were to happen
very
frequently to the miners, or if they could not safely guard against such
risks by any means. Who would not prefer to live rather than to possess
all things, even the
metals? For he who thus perishes possesses nothing,
but relinquishes all to his
heirs. But since things like this rarely happen,
and only in so far as workmen
are careless, they do not deter miners from
carrying on their trade any
more than it would deter a carpenter from his,
because one of his mates
has acted incautiously and lost his life by falling
from a high
building. I have thus answered each argument which critics are
wont to put before
me when they assert that mining is an undesirable occuppa
tion,
because it involves expense with uncertainty of return, because it is
changeable, and because it is dangerous to those engaged in it.
Now I come to those critics who say that mining is not useful to the
rest of mankind because forsooth, gems, metals, and other mineral
products
are worthless in themselves. This admission they try to extort from us,
partly by arguments and
examples, partly by misrepresentations and abuse of
us. First, they make use of this argument: “The earth does not conceal
and remove from our eyes those things which are useful and necessary to
in large abundance from her bounty and brings
into the light of day the
herbs, vegetables, grains, and fruits, and
the trees. The minerals on the
other hand she buries far beneath in the depth of
the ground; therefore,
they should not be sought. But they are dug out by wicked men who, as
the poets say, are the
products of the Iron Age.” Ovid censures their
audacity in the
following lines:—
“And not only was the rich soil required to furnish corn and due
sustenance, but men even descended into the entrails of the earth, and
they dug up riches, those incentives to vice, which the earth had
hidden
and had removed to the Stygian shades. Then destructive iron came
forth, and gold, more destructive than iron;
then war came forth.”
Another of their arguments is this: Metals offer to men no advantages,
therefore we ought not to search them out. For whereas man is composed
of soul and body, neither is in want of
minerals. The sweetest food of the
soul is the contemplation of nature, a
knowledge of the finest arts and sciences,
an understanding of virtue;
and if he interests his mind in excellent things,
if he exercise his
body, he will be satisfied with this feast of noble thoughts and
knowledge, and have no desire for other things. Now although the human
body may be content with necessary food and
clothing, yet the fruits of the
earth and the animals of different
kinds supply him in wonderful abundance
with food and drink, from which
the body may be suitably nourished and
strengthened and life prolonged
to old age. Flax, wool, and the skins of
many animals provide plentiful clothing low
in price; while a luxurious kind,
not hard to procure—that is the
so called
down of trees and the webs of the silk worm. So that the body has absolutely
no need of the metals, so hidden in the
depths of the earth and for the greater
part very expensive. Wherefore it is said that this maxim of Euripides is
approved in
assemblies of learned men, and with good reason was always on
the lips
of Socrates:
“Works of silver and purple are of use, not for human life, but
rather for Tragedians.”
These critics praise also this saying from Timocreon of Rhodes:
“O Unseeing Plutus, would that thou hadst never appeared in the
earth or in the sea or on the land, but that thou didst have thy
habita
tion in Tartarus and Acheron, for out of thee arise all evil
things which
overtake mankind”
They greatly extol these lines from Phocylides:
“Gold and silver are injurious to mortals; gold is the source of
crime, the plague of life, and the ruin of all things. Would that thou
were not such an attractive scourge! because of thee
arise robberies,
children against parents.”
This from Naumachius also pleases them:
“Gold and silver are but dust, like the stones that lie
scattered
the pebbly beach, or on the margins of the
rivers.”
On the other hand, they censure these verses of Euripides:
“Plutus is the god for wise men: all else is mere folly and at
t
same time a deception in words.”
So in like manner these lines from Theognis:
“O Plutus, thou most beautiful and placid god! whilst I have
th
however bad I am, I can be regarded as good.”
They also blame Aristodemus, the Spartan, for these words:
“Money makes the man; no one who is poor is either
good
honoured.”
And they rebuke these songs of Timocles:
“Money is the life and soul of mortal men.
He who has n
heaped up riches for himself wanders like a dead man
amongst t
living.”
Finally, they blame Menander when he wrote:
“Epicharmus asserts that the gods are water, wind, fire, earth,
su
and stars. But I am of opinion that the gods of any use to us are silv
and
gold; for if thou wilt set these up in thy house thou mayest
se
whatever thou wilt. All things will fall to thy lot; land, houses, slav
silver-work;
moreover friends, judges, and witnesses. Only give free
for thus thou hast the gods to serve
thee.”
But besides this, the strongest argument of the detractors is that
t
fields are devastated by mining operations, for which reason
forme
Italians were warned by law that no one should dig the earth
for metals a
so injure their very fertile fields, their vineyards,
and their olive grov
Also they argue that the woods and groves are
cut down, for there is need
an endless amount of wood for timbers,
machines, and the smelting of meta
And when the woods and groves
are felled, then are exterminated the bea
and birds, very many of
which furnish a pleasant and agreeable food for ma
Further, when
the ores are washed, the water which has been used pois
the brooks
and streams, and either destroys the fish or drives them
awa
Therefore the inhabitants of these regions, on account of the
devastation
their fields, woods, groves, brooks and rivers, find
great difficulty in procur
the necessaries of life, and by reason
of the destruction of the timber th
are forced to greater expense
in erecting buildings. Thus it is said, it
clear to all that there is greater detriment
from mining than the value
the metals which the mining
produces.
So in fierce contention they clamour, showing by such
examples
follow that every great man has been content with virtue,
and despis
metals. They praise Bias because he esteemed the metals mer
as fortune's
playthings, not as his real wealth. When his enemies h
captured his native Priene, and his
fellow-citizens laden with precious thin
away none of
his goods with him, and he replied, “I carry all my possessions
with me.” And it is said that Socrates, having received twenty
minae sent
to him by Aristippus, a grateful disciple, refused them and
sent them back to
him by the command of his conscience. Aristippus, following his example
in this matter, despised gold and
regarded it as of no value. And once
when he was making a journey with his slaves, and they, laden
with the
gold, went too slowly, he ordered them to keep only as much of
it as they
could carry without distress and to throw away the
remainderMoreover,
Anacreon of Teos, an ancient and noble poet, because he had
been troubled
about them for two nights, returned five talents which
had been given him
by Polycrates, saying that they were not worth the
anxiety which he had
gone through on their account. In like manner celebrated and exceedingly
powerful princes have imitated
the philosophers in their scorn and contempt
for gold and silver. There was for example, Phocion, the Athenian, who was
appointed general
of the army so many times, and who, when a large sum of gold
was sent
to him as a gift by Alexander, King of Macedon, deemed it trifling and
scorned it. And Marcus Curius ordered the gold to be carried back to the
Samnites,
as did also Fabricius Luscinus with regard to the silver and
copper. And certain Republics have forbidden their citizens the use and
employment of gold and silver by law and ordinance; the Lacedaemonians,
by the decrees and ordinances of Lycurgus, used diligently to enquire
among
their citizens whether they possessed any of these things or not,
and the
possessor, when he was caught, was punished according to law
and justice. The inhabitants of a town on the Tigris, called Babytace, buried their gold
in the ground so that no one should use it. The Scythians condemned the
use of gold and silver so that they might
not become avaricious.
Further are the metals reviled; in the first place people wantonly
abuse
gold and silver and call them deadly and nefarious pests of the human
race, because those who possess them are in the greatest peril, for
those who
have none lay snares for the possessors of wealth, and thus
again and again
the metals have been the cause of destruction and ruin. For example,
Polymnestor, King of Thrace, to obtain possession of his
gold, killed Polydorus,
his noble guest and the son of Priam, his
father-in-law, and old friend. Pygmalion, the King of Tyre, in order that he might seize treasures of gold
and silver, killed his sister's husband, a priest, taking no account of
either
kinship or religion. For love of gold Eriphyle betrayed her husband
Amphiaraus to his enemy. Likewise Lasthenes betrayed the city of
Olynthus to Philip of Macedon. The daughter of Spurius Tarpeius, having
been bribed with gold, admitted
the Sabines into the citadel of Rome. Claudius Curio sold his country for gold to Cæsar, the Dictator.
Gold, too,
was the cause of the downfall of Aesculapius, the great
physician, who it was
believed was the son of Apollo. Similarly Marcus Crassus, through his
eager desire for the gold of the
Parthians, was completely overcome together
with his son and eleven
legions, and became the jest of his enemies; for they
“Thou hast thirsted for gold, therefore drink gold.”
But why need I cite here these many examples from history?
almost our daily experience to
learn that, for the sake of obtaining gold and
silver, doors are burst
open, walls are pierced, wretched travellers are struck
down by
rapacious and cruel men born to theft, sacrilege, invasion, and
robbery. We see thieves seized and strung up before us, sacrilegious persons
burnt alive, the limbs of robbers broken on the wheel, wars waged for
the
same reason, which are not only destructive to those against whom
they are
waged, but to those also who carry them on. Nay, but they say that the
precious metals foster all manner of vice,
such as the seduction of women,
adultery, and unchastity, in short,
crimes of violence against the person. Therefore the Poets, when they represent Jove transformed into a golden
shower and falling into the lap of Danae, merely mean that he had found
for himself a safe road by the use of gold, by which he might enter the
tower
for the purpose of violating the maiden. Moreover, the fidelity of many
men is overthrown by the love of gold and
silver, judicial sentences are
bought, and innumerable crimes are
perpetrated. For truly, as Propertius
says:
“This is indeed the Golden Age.
The greatest rewards come from
gold; by gold love is won; by gold is
faith destroyed; by gold is justice
bought; the law follows the track
of gold, while modesty will soon
follow it when law is gone.”
Diphilus says:
“I consider that nothing is more powerful than gold.
By it all
things are torn asunder; all things are
accomplished.”
Therefore, all the noblest and best despise these riches, deservedly and
with justice, and esteem them as nothing. And this is said by the old man
in Plautus:
“I hate gold.
It has often impelled many people to many wrong
acts.”
In this country too, the poets inveigh with stinging reproaches against money
coined from gold and silver. And especially did Juvenal:
“Since the majesty of wealth is the most sacred thing among us;
although, O pernicious money, thou dost not yet inhabit a temple, nor
have we erected altars to money.”
And in another place:
“Demoralising money first introduced foreign customs, and
voluptuous wealth weakened our race with disgraceful
luxury.”
And very many vehemently praise the barter system which men used before
money was devised, and which even now obtains among certain simple
peoples.
And next they raise a great outcry against other metals, as iron, than
life of man. For it is employed in making swords, javelins, spears, pikes,
arrows—weapons by which men are wounded, and which cause
slaughter,
robbery, and wars. These things so moved the wrath of Pliny that he wrote:
“Iron is
used not only in hand to hand fighting, but also to form the winged
missiles of war, sometimes for hurling engines, sometimes for lances,
some
times even for arrows. I look upon it as the most deadly fruit of human
ingenuity. For to bring Death to men more quickly we have given wings to
iron and
taught it to fly.”
from the catapult and other
engines can be driven into the body of only one
man, while the iron
cannon-ball fired through the air, can go through the
bodies of many
men, and there is no marble or stone object so hard that it
cannot be
shattered by the force and shock. Therefore it levels the highest
towers to the ground, shatters and
destroys the strongest walls. Certainly
the ballistas which throw stones, the battering rams and other
ancient war
engines for making breaches in walls of fortresses and
hurling down strong
holds, seem to have little power in comparison
with our present cannon. These emit horrible sounds and noises, not less than thunder, flashes
of
fire burst from them like the lightning, striking, crushing, and
shatter
ing buildings, belching forth flames and kindling fires
even as lightning
flashes. So that with more justice could it be said of the impious men of
our age
than of Salmoneus of ancient days, that they had snatched lightning
from Jupiter and wrested it from his hands. Nay, rather there has been
sent from the infernal regions to the earth
this force for the destruction of
men, so that Death may snatch to
himself as many as possible by one stroke.
But because muskets are nowadays rarely made of iron, and the large
ones
never, but of a certain mixture of copper and tin, they confer more
maledictions on copper and tin than on iron. In this connection too, they
mention the brazen bull of Phalaris, the
brazen ox of the people of Per
gamus, racks in the shape of an iron
dog or a horse, manacles, shackles,
wedges, hooks, and red-hot plates. Cruelly racked by such instruments,
people are driven to confess crimes
and misdeeds which they have never
committed, and innocent men are
miserably tortured to death by every
conceivable kind of torment.
It is claimed too, that lead is a pestilential and noxious metal, for men
are punished by means of molten lead, as Horace describes in the ode
addressed to the Goddess Fortune: “Cruel Necessity ever goes
before thee
bearing in her brazen hand the spikes and wedges, while the
awful hook and
molten lead are also not lacking.”
for this metal, they are not silent about the leaden balls of muskets,
and they
find in it the cause of wounds and death.
They contend that, inasmuch as Nature has concealed metals far within
the depths of the earth, and because they are not necessary to human
life,
they are therefore despised and repudiated by the noblest, and
should not be
cause of very great evils, it follows
that mining is not useful to mankind
but on the contrary harmful and
destructive. Several good men have
been so perturbed by these tragedies that they
conceive an intensely bitter
hatred toward metals, and they wish
absolutely that metals had never been
created, or being created, that
no one had ever dug them out. The more I
commend the singular honesty, innocence, and goodness of such
men, the
more anxious shall I be to remove utterly and eradicate all
error from their
minds and to reveal the sound view, which is that the
metals are most useful
to mankind.
In the first place then, those who speak ill of the metals and refuse to
make use of them, do not see that they accuse and condemn as wicked the
Creator Himself, when they assert that He fashioned some things vainly
and without good cause, and thus they regard Him as the Author of evils
which opinion is certainly not worthy of pious and sensible men.
In the next place, the earth does not conceal metals in her depths
because she does not wish that men should dig them out, but because
provident and sagacious Nature has appointed for each thing its place. She
generates them in the veins, stringers, and seams in the rocks, as
though
in special vessels and receptacles for such material. The metals cannot be
produced in the other elements because the
materials for their formation
are wanting. For if they were generated in the air, a thing that rarely
happens, they
could not find a firm resting-place, but by their own force and
weight
would settle down on to the ground. Seeing then that metals have
their proper abiding place in the bowels of
the earth, who does not see that
these men do not reach their
conclusions by good logic?
They say, “Although metals are in the earth, each located in its own
proper place where it originated, yet because they lie thus enclosed
and
hidden from sight, they should not be taken out.” But, in
refutation of these
attacks, which are so annoying, I will on behalf of
the metals instance the
fish, which we catch, hidden and concealed
though they be in the water, even
in the sea. Indeed, it is far stranger that man, a terrestrial animal, should
search
the interior of the sea than the bowels of the earth. For as birds are
born to fly freely through the air, so are fishes born
to swim through the
waters, while to other creatures Nature has given
the earth that they might
live in it, and particularly to man that he
might cultivate it and draw out
of its caverns metals and other mineral
products. On the other hand, they
say that we eat fish, but neither hunger nor
thirst is dispelled by minerals,
nor are they useful in clothing the
body, which is another argument by
which these people strive to prove
that metals should not be taken out. But
man without metals cannot provide those things which he needs for
food and
clothing. For, though the produce of the land furnishes the greatest
abundance of
food for the nourishment of our bodies, no labour can be
carried on and
completed without tools. The ground itself is turned up
with ploughshares and harrows, tough
stalks and the tops of the roots are
broken off and dug up with a
mattock, the sown seed is harrowed, the corn
by
scythes and threshed on the floor, or its ears are cut off and stored in the
barn and later beaten with flails and winnowed with fans, until finally
the
pure grain is stored in the granary, whence it is brought forth
again when
occasion demands or necessity arises. Again, if we wish to procure better
and more productive fruits from
trees and bushes, we must resort to
cultivating, pruning, and grafting,
which cannot be done without tools. Even as without vessels we cannot keep or hold liquids, such as milk, honey,
wine, or oil, neither could so many living things be cared for without
buildings to protect them from long-continued rain and intolerable
cold. Most of the rustic instruments are made of iron, as ploughshares,
share
beams, mattocks, the prongs of harrows, hoes, planes,
hay-forks, straw
cutters, pruning shears, pruning hooks, spades,
lances, forks, and weed
cutters. Vessels are also made of copper or lead.
Neither are wooden
instruments or vessels made without iron. Wine cellars, oil-mills, stables,
or any other part of a farm building
could not be built without iron tools. Then if the bull, the wether, the goat, or any other domestic animal is led
away from the pasture to the butcher, or if the poulterer brings from
the farm
a chicken, a hen, or a capon for the cook, could any of these
animals be cut
up and divided without axes and knives? I need say nothing here about
bronze and copper pots for cooking,
because for these purposes one could
make use of earthen vessels, but
even these in turn could not be made and
fashioned by the potter
without tools, for no instruments can be made out
of wood alone,
without the use of iron. Furthermore, hunting, fowling, and
fishing supply man with food, but
when the stag has been ensnared does not
the hunter transfix him with
his spear? As he stands or runs, does he not
pierce him with an arrow? Or pierce him with a bullet?
Does not the
fowler in the same way kill the moor-fowl or pheasant with
an arrow? Or
does he not discharge into its body the ball from the musket? I will not
speak of the snares and other instruments with which the
woodcock, wood
pecker, and other wild birds are caught, lest I
pursue unseasonably and too
minutely single instances. Lastly, with his fish-hook and net does not the
fisherman catch the fish
in the sea, in the lakes, in fish-ponds, or in rivers? But the hook is of iron, and sometimes we see lead or iron weights attached
to the net. And most fish that are caught are afterward cut up and
dis
embowelled with knives and axes. But, more than enough has been said on
the matter of food.
Now I will speak of clothing, which is made out of wool, flax, feathers,
hair, fur, or leather. First the sheep are sheared, then the wool is combed.
Next the threads are drawn out, while later the warp is suspended in the
shuttle under which passes the wool. This being struck by the comb, at length
cloth is formed either from
threads alone or from threads and hair. Flax,
when gathered, is first pulled by hooks. Then it is dipped in water and
afterward dried, beaten into tow with a
heavy mallet, and carded, then
drawn out into threads, and finally
woven into cloth. But has the artisan
or weaver of the cloth any instrument not made of
iron? Can one be made
The cloth or web must be cut into lengths
for the tailor. Can this be done without knife or scissors?
Can the tailor
sew together any garments without a needle? Even peoples dwelling beyond
the seas cannot make a covering for their
bodies, fashioned of feathers,
without these same implements. Neither can the furriers do without them
in sewing together the pelts of
any kind of animals. The shoemaker needs
a knife to cut the leather, another to scrape it,
and an awl to perforate it
before he can make shoes. These coverings for the body are either woven
or stitched. Buildings too, which protect the same body from rain, wind,
cold, and
heat, are not constructed without axes, saws, and augers.
But what need of more words?
If we remove metals from the service
of man, all methods of protecting
and sustaining health and more care
fully preserving the course of
life are done away with. If there were no
metals, men would pass a horrible and wretched
existence in the midst of
wild beasts; they would return to the acorns
and fruits and berries of the
forest. They would feed upon the herbs and roots which they plucked up
with
their nails. They would dig out caves in which to lie down at night,
and by day they
would rove in the woods and plains at random like beasts,
and inasmuch
as this condition is utterly unworthy of humanity, with its
splendid
and glorious natural endowment, will anyone be so foolish or
obstinate
as not to allow that metals are necessary for food and clothing and
that they tend to preserve life?
Moreover, as the miners dig almost exclusively in mountains otherwise
unproductive, and in valleys invested in gloom, they do either slight
damage
to the fields or none at all. Lastly, where woods and glades are cut down,
they may be sown with grain
after they have been cleared from the roots of
shrubs and trees. These new fields soon produce rich crops, so that they repair
the losses
which the inhabitants suffer from increased cost of timber. More
over, with the metals which are melted from the ore, birds
without number,
edible beasts and fish can be purchased elsewhere and
brought to these
mountainous regions.
I will pass to the illustrations I have mentioned.
Bias of Priene, when his
country was taken, carried away out of the city
none of his valuables. So
strong a man with such a reputation for wisdom had no need to fear
personal
danger from the enemy, but this in truth cannot be said of him
because he
hastily took to flight; the throwing away of his goods does
not seem to me
so great a matter, for he had lost his house, his
estates, and even his country,
than which nothing is more precious. Nay, I should be convinced of Bias's
contempt and scorn for possessions
of this kind, if before his country was
captured he had bestowed them
freely on relations and friends, or had
distributed them to the very
poor, for this he could have done freely and
without question. Whereas his conduct, which the Greeks admire so
greatly, was due, it
would seem, to his being driven out by the enemy and
stricken with
fear. Socrates in truth did not despise gold, but would not
accept money for
his teaching. As for Aristippus of Cyrene, if he had gath
ered and saved the gold
which he ordered his slaves to throw away, he might
would not. by reason of his poverty, have then been obliged to flatter the
tyrant
Dionysius, nor would he ever have been called by him a King's dog. For this reason Horace, speaking of Damasippus when reviling Staberus for
valuing riches very highly, says:
“What resemblance has the Grecian Aristippus to this fellow?
He who commanded his slaves to throw away the gold in the midst of
Libya
because they went too slowly, impeded by the weight of their
burden—which of these two men is the more insane?”
Insane indeed is he who makes more of riches than of virtue.
Insane
also is he who rejects them and considers them as worth nothing,
instead of
using them with reason. Yet as to the gold which Aristippus on another
occasion flung into the
sea from a boat, this he did with a wise and prudent
mind. For learning that it was a pirate boat in which he was sailing, and
fearing for his life, he counted his gold and then throwing it of his
own will
into the sea, he groaned as if he had done it unwillingly. But afterward,
when he escaped the peril, he said: “It is better
that this gold itself should
be lost than that I should have perished
because of it.” Let it be granted
that some philosophers, as well
as Anacreon of Teos, despised gold and
silver. Anaxagoras of Clazomenae also gave up his sheep-farms and
became a
shepherd. Crates the Theban too, being annoyed that his
estate and other kinds of
wealth caused him worry, and that in his con
templations his mind
was thereby distracted, resigned a property valued at
ten talents, and
taking a cloak and wallet, in poverty devoted all his
thought and
efforts to philosophy. Is it true that because these philo
sophers despised money, all
others declined wealth in cattle? Did they
refuse to cultivate lands or to dwell in houses? There were certainly many,
on the other hand, who, though affluent,
became famous in the pursuit of
learning and in the knowledge of divine
and human laws, such as Aristotle,
Cicero, and Seneca. As for Phocion, he did not deem it honest to accept the
gold sent to him
by Alexander. For if he had consented to use it, the
king as much as himself would
have incurred the hatred and aversion of
the Athenians, and these very
people were afterward so ungrateful toward
this excellent man that they
compelled him to drink hemlock. For what
would have been less becoming to Marcus Curius and Fabricius
Luscinus
than to accept gold from their enemies, who hoped that by
these means
those leaders could be corrupted or would become odious to
their fellow
citizens, their purpose being to cause dissentions among
the Romans and
destroy the Republic utterly. Lycurgus, however, ought to have given
instructions to the Spartans as
to the use of gold and silver, instead of
abolishing things good in
themselves. As to the Babytacenses, who does
not see that they were senseless and
envious? For with their gold they might
have bought things of which they were in
need, or even given it to neigh
bouring peoples to bind them more
closely to themselves with gifts and
favours. Finally, the Scythians, by condemning the use of gold and silver
enjoying them, one who can possess other
forms of property may also
become avaricious.
Now let us reply to the attacks hurled against the products of mines.
In the first place, they call gold and silver the scourge of mankind because
they are the cause of destruction and ruin to their possessors. But in this
manner, might not anything that we possess be called a
scourge to
human kind,—whether it be a horse, or a garment, or
anything else? For, whether one rides a splendid horse, or journeys well clad, he would
give occasion to a robber to kill him. Are we then not to ride on horses,
but to journey on foot, because a
robber has once committed a murder in
order that he may steal a horse? Or are we not to possess clothing, because
a vagabond with a sword has
taken a traveller's life that he may rob him
of his garment? The possession of gold and silver is similar.
Seeing
then that men cannot conveniently do all these things, we should
be on our
guard against robbers, and because we cannot always protect
ourselves
from their hands, it is the special duty of the magistrate to
seize wicked and
villainous men for torture, and, if need be, for
execution.
Again, the products of the mines are not themselves the cause of war.
Thus, for example, when a tyrant, inflamed with passion for a woman of
great beauty, makes war on the inhabitants of her city, the fault lies
in the
unbridled lust of the tyrant and not in the beauty of the woman. Likewise,
when another man, blinded by a passion for gold and silver,
makes war
upon a wealthy people, we ought not to blame the metals but
transfer all
blame to avarice. For frenzied deeds and disgraceful actions, which are
wont to weaken and
dishonour natural and civil laws, originate from our
own vices. Wherefore Tibullus is wrong in laying the blame for war on
gold, when he
says: “This is the fault of a rich man's gold; there were
no wars
when beech goblets were used at banquets.” But Virgil, speaking of
Polymnestor, says that the crime of the murderer rests on avarice:
“He breaks all law; he murders Polydorus, and obtains gold by
violence. To what wilt thou not drive mortal hearts, thou accursed
hunger for
gold?”
And again, justly, he says, speaking of Pygmalion, who killed Sichaeus:
“And blinded with the love of gold, he slew him unawares with
stealthy sword.”
For lust and eagerness after gold and other things make men blind, and
this wicked greed for money, all men in all times and places have
considered
dishonourable and criminal. Moreover, those who have been so addicted to
avarice as to be its slaves
have always been regarded as mean and sordid. Similarly, too, if by means of gold and silver and gems men can overcome
the chastity of women, corrupt the honour of many people, bribe the
course
of justice and commit innumerable wickednesses, it is not the
metals which
are to be blamed, but the evil passions of men which
become inflamed and
ignited; or it is due to the blind and impious
desires of their minds. But
against money, yet inasmuch as the Poets one after
another condemn it,
their criticism must be met, and this can be done
by one argument alone. Money is good for those who use it well; it brings loss and evil to those who
use it ill. Hence, very rightly, Horace says:
“Dost thou not know the value of money; and what uses it serves?
It buys bread, vegetables, and a pint of wine.”
And again in another place:
“Wealth hoarded up is the master or slave of each possessor; it
should follow rather than lead, the ‘twisted rope.’
”
When ingenious and clever men considered carefully the system of barter,
which ignorant men of old employed and which even to-day is used by
certain uncivilised and barbarous races, it appeared to them so
troublesome
and laborious that they invented money. Indeed, nothing more useful
could have been devised, because a small
amount of gold and silver is of as
great value as things cumbrous and
heavy; and so peoples far distant from one
another can, by the use of
money, trade very easily in those things which
civilised life can
scarcely do without.
The curses which are uttered against iron, copper, and lead have no
weight with prudent and sensible men, because if these metals were done
away with, men, as their anger swelled and their fury became unbridled,
would assuredly fight like wild beasts with fists, heels, nails, and
teeth. They would strike each other with sticks, hit one another with stones, or
dash their foes to the ground. Moreover, a man does not kill another with
iron alone, but slays by
means of poison, starvation, or thirst. He may
seize him by the throat and strangle him; he may bury him alive
in the
ground; he may immerse him in water and suffocate him; he may
burn
or hang him; so that he can make every element a participant in
the death
of men. Or, finally, a man may be thrown to the wild beasts.
Another
may be sewn up wholly except his head in a sack, and thus be
left to be
devoured by worms; or he may be immersed in water until he
is torn to
pieces by sea-serpents. A man may be boiled in oil; he may be greased,
tied with ropes, and left
exposed to be stung by flies and hornets; he may
be put to death by
scourging with rods or beating with cudgels, or struck
down by stoning,
or flung from a high place. Furthermore, a man
may be tortured in more ways than one without the use
of metals; as when
the executioner burns the groins and armpits of his
victim with hot wax;
or places a cloth in his mouth gradually, so that
when in breathing he
draws it slowly into his gullet, the executioner
draws it back suddenly and
violently; or the victim's hands are
fastened behind his back, and he is
drawn up little by little with a
rope and then let down suddenly. Or
similarly, he may be tied to a beam and a heavy stone fastened by a
cord to his feet, or finally his limbs may be torn asunder. From these
examples we see that it is not metals that are to be
condemned, but our
vices, such as anger, cruelty, discord, passion for
power, avarice, and lust.
The question next arises, whether we ought to count metals amongst
the
number of good things or class them amongst the bad. The Peripatetics
regarded all wealth as a good thing, and merely spoke
of externals as having
to do with neither the mind nor the body. Well, let riches be an external
thing. And, as they said, many other things may be classed as good if it is
in
one's power to use them either well or ill. For good men employ them for
good, and to them they are useful. The wicked use them badly, and to
them they are harmful. There is a saying of Socrates, that just as wine
is influenced by the
cask, so the character of riches is like their possessors. The Stoics, whose custom it is to argue subtly and acutely, though they did
not put wealth in the category of good things, they did not count it
amongst
the evil ones, but placed it in that class which they term
neutral. For to
them virtue alone is good, and vice alone evil. The whole of what remains
is indifferent. Thus, in their conviction, it matters not whether one be in
good health
or seriously ill; whether one be handsome or deformed. In
short:
“Whether, sprung from Inachus of old, and thus hast lived
beneath
the sun in wealth, or hast been poor and despised among men,
it matters
not.”
For my part, I see no reason why anything that is in itself of use should
not be placed in the class of good things. At all events, metals are a
creation of Nature, and they supply many
varied and necessary needs of the
human race, to say nothing about
their uses in adornment, which are so
wonderfully blended with utility. Therefore, it is not right to degrade them
from the place they hold
among the good things. In truth, if there is a
bad use made of them, should they on that
account be rightly called evils? For of what good things can we not make an equally bad or good use?
Let
me give examples from both classes of what we term good. Wine, by far
the best drink, if drunk in moderation, aids the digestion
of food, helps to
produce blood, and promotes the juices in all parts
of the body. It is of use
in nourishing not only the body but the mind as well, for
it disperses our
dark and gloomy thoughts, frees us from cares and
anxiety, and restores
our confidence. If drunk in excess, however, it injures and prostrates the
body with
serious disease. An intoxicated man keeps nothing to himself;
he raves and rants, and
commits many wicked and infamous acts. On
this subject Theognis wrote some very clever lines, which we may
render
thus:
“Wine is harmful if taken with greedy lips, but if drunk in
moderation it is wholesome.”
But I linger too long over extraneous matters.
I must pass on to the
gifts of body and mind, amongst which strength,
beauty, and genius
occur to me. If then a man, relying on his strength, toils hard to maintain
himself
and his family in an honest and respectable manner, he uses the
gift
aright, but if he makes a living out of murder and robbery, he uses it
wrongly. Likewise, too, if a lovely woman is anxious to please her husband
of passion, she misuses her beauty. In like manner, a youth who devotes
himself to learning and cultivates
the liberal arts, uses his genius rightly. But he who dissembles, lies, cheats, and deceives by fraud and dishonesty,
misuses his abilities. Now, the man who, because they are abused, denies that
wine, strength,
beauty, or genius are good things, is unjust and blasphemous
towards
the Most High God, Creator of the World; so he who would remove
metals
from the class of blessings also acts unjustly and blasphemously
against Him. Very true, therefore, are the words which certain Greek
poets have
written, as Pindar:
“Money glistens, adorned with virtue; it supplies the means by
which thou mayest act well in whatever circumstances fate may
have
in store for thee.”
And Sappho:
“Without the love of virtue gold is a dangerous and harmful guest,
but when it is associated with virtue, it becomes the source and height
of good.”
And Callimachus:
“Riches do not make men great without virtue; neither do virtues
themselves make men great without some wealth.”
And Antiphanes:
“Now, by the gods, why is it necessary for a man to grow rich?
Why does he desire to possess much money unless that he may, as
much as
possible, help his friends, and sow the seeds of a harvest of
gratitude, sweetest of the goddesses.”
Having thus refuted the arguments and contentions of adversaries,
let us
sum up the advantages of the metals. In the first place, they are
useful to the physician, for they furnish
liberally the ingredients for medi
cines, by which wounds and
ulcers are cured, and even plagues; so that
certainly if there were no
other reasons why we should explore the depths of
the earth, we should
for the sake of medicine alone dig in the mines. Again,
the metals are of use to painters, because they yield certain
pigments which,
when united with the painter's slip, are injured less
than others by the moisture
from without. Further, mining is useful to the architects, for thus is found
marble,
which is suitable not only for strengthening large buildings, but
also
for decoration. It is, moreover, helpful to those whose ambition urges
them toward
immortal glory, because it yields metals from which are made
coins,
statues, and other monuments, which, next to literary records, give men
in a sense immortality. The metals are useful to merchants with very great cause,
for, as I have
stated elsewhere, the use of money which is made from metals is
much
more convenient to mankind than the old system of exchange of
commodi
ties. In short, to whom are the metals not of use?
In very truth, even the works
of art, elegant, embellished, elaborate,
useful, are fashioned in various shapes by
the artist from the metals
gold, silver, brass, lead, and iron. How few artists
Ev
if tools of iron or brass were not used, we could not make tools
of wood a
stone without the help of metal. From all these examples are evident t
benefits and advantages
derived from metals. We should not have ha
these at all unless the science of mining and
metallurgy had been discovere
and handed down to us. Who then does not understand how highly usef
they are, nay rather,
how necessary to the human race? In a word, ma
could not do without the mining industry, nor did
Divine Providence wi
that he should.
Further, it has been asked whether to work in metals is
honourab
employment for respectable people or whether it is not
degrading an
dishonourable. We ourselves count it amongst the honourable arts.
Fo
that art, the pursuit of which is unquestionably not impious,
nor offensive
nor mean, we may esteem honourable. That this is the nature of th
mining profession, inasmuch as it
promotes wealth by good and hones
methods, we shall show
presently. With justice, therefore, we may clas
it amongst honourable
employments. In the first place, the occupatio
of the miner, which I must be
allowed to compare with other methods o
acquiring great wealth, is
just as noble as that of agriculture; for, as th
farmer, sowing
his seed in his fields injures no one, however profitable they
may
prove to him, so the miner digging for his metals, albeit he draws
forth
great heaps of gold or silver, hurts thereby no mortal man. Certainly these
two modes of increasing wealth are in the highest
degree both noble and
honourable. The booty of the soldier, however, is frequently impious,
because
in the fury of the fighting he seizes all goods, sacred as well
as
profane. The most just king may have to declare war on cruel tyrants,
but in the
course of it wicked men cannot lose their wealth and possessions
without dragging into the same calamity innocent and poor people, old
men, matrons, maidens, and orphans. But the miner is able to accumu
late great riches in a short time,
without using any violence, fraud, o
malice. That old saying is, therefore, not always true that “Every rich
man is either wicked himself, or is the heir to wickedness.”
Some, however, who contend against us, censure and attack miners by
saying that they and their children must needs fall into penury after a
short
time, because they have heaped up riches by improper means. According
to them nothing is truer than the saying of the poet
Naevius:
“Ill gotten gains in ill fashion slip away.”
The following are some of the wicked and sinful methods by which
they
say men obtain riches from mining. When a prospect of obtaining
metals shows itself in a mine, either the
ruler or magistrate drives out the
rightful owners of the mines from
possession, or a shrewd and cunning
neighbour perhaps brings a law-suit
against the old possessors in order to
rob them of some part of their
property. Or the mine superintendent imposes
on the owners such a heavy
contribution on shares, that if they cannot pay,
or will not, they lose
their rights of possession; while the superintendent,
contrary to all
that is right, seizes upon all that they have lost. Or,
clay that part where the metal abounds, or by
covering it with earth,
stones, stakes, or poles, in the hope that
after several years the pro
prietors, thinking the mine exhausted,
will abandon it, and the foreman
can then excavate that remainder of
the ore and keep it for himself. They even state that the scum of the miners exist wholly by fraud,
deceit, and lying. For to speak of nothing else, but only of those
deceits which are
practised in buying and selling, it is said they either
advertise the
veins with false and imaginary praises, so that they can
sell the
shares in the mines at one-half more than they are worth, or
on the
contrary, they sometimes detract from the estimate of them so
that they
can buy shares for a small price. By exposing such frauds our
critics suppose all good opinion of miners
is lost. Now, all wealth,
whether it has been gained by good or evil means, is
liable by some adverse
chance to vanish away. It decays and is dissipated by the fault and care
lessness of the
owner, since he loses it through laziness and neglect, or
wastes and
squanders it in luxuries, or he consumes and exhausts it in gifts,
or
he dissipates and throws it away in gambling:
“Just as though money sprouted up again, renewed from an exhausted
coffer, and was always to be obtained from a full heap.”
It is therefore not to be wondered at if miners do not keep in mind the
counsel given by King Agathocles: “Unexpected fortune should be
held
in reverence,” for by not doing so they fall into penury;
and particularly
when the miners are not content with moderate riches,
they not rarely spend
on new mines what they have accumulated from
others. But no just ruler
or magistrate deprives owners of their possessions;
that, however, may be
done by a tyrant, who may cruelly rob his
subjects not only of their goods
honestly obtained, but even of life
itself. And yet whenever I have inquired
into the complaints which are in common
vogue, I always find that the
owners who are abused have the best of
reasons for driving the men from
the mines; while those who abuse the
owners have no reason to complain
about them. Take the case of those who, not having paid their contributions,
have
lost the right of possession, or those who have been expelled by the
magis
trate out of another man's mine: for some wicked men, mining
the small
veins branching from the veins rich in metal, are wont to
invade the property
of another person. So the magistrate expels these men accused of wrong,
and drives them
from the mine. They then very frequently spread
unpleasant rumours concerning this
amongst the populace. Or, to take
another case: when, as often happens, a dispute arises
between neighbours,
arbitrators appointed by the magistrate settle it,
or the regular judges
investigate and give judgment. Consequently, when the judgment is given,
inasmuch as each party has
consented to submit to it, neither side should
complain of injustice;
and when the controversy is adjudged, inasmuch as
the decision is in
accordance with the laws concerning mining, one of the
parties cannot
be injured by the law. I do not vigorously contest the point,
that at times a mine
superintendent may exact a larger contribution Nay, I will admit that a for
man may plaster over, or hide with a
structure, a vein where it is rich i
metals. Is the wickedness of one or two to brand the many honest wit
fraud
and trickery? What body is supposed to be more pious and virtuou
in the Republic
than the Senate? Yet some Senators have been detecte
in peculations, and have been
punished. Is this any reason that so honour
able a house should lose its good
name and fame? The superintenden
cannot exact contributions from the owners
without the knowledge an
permission of the Bergmeister or the
deputies; for this reason decep
tion of this kind is impossible. Should the foremen be convicted o
fraud, they are beaten with rods;
or of theft, they are hanged. I
is complained that some sellers and buyers of the shares in mines
ar
fraudulent. I concede it.
But can they deceive anyone except a stupid
careless man, unskilled
in mining matters? Indeed, a wise and pruden
man, skilled in this art, if he doubts
the trustworthiness of a seller o
buyer, goes at once to the mine
that he may for himself examine the vei
which has been so greatly
praised or disparaged, and may consider whethe
he will buy or sell
the shares or not. But people say, though such an on
can be on his guard against
fraud, yet a simple man and one who is easil
credulous, is
deceived. But we frequently see a man who is trying to mislea
another in this
way deceive himself, and deservedly become a laughing
stock for
everyone; or very often the defrauder as well as the dupe
i
entirely ignorant of mining. If, for instance, a vein has been found to b
abundant in ore,
contrary to the idea of the would-be deceiver, then he wh
was to
have been cheated gets a profit, and he who has been the
deceive
loses. Nevertheless, the miners themselves rarely buy or sell shares,
bu
generally they have
have been
instructed to give or accept. Seeing therefore, that magistrate
decide disputes on fair and just
principles, that honest men deceive nobody
while a dishonest one
cannot deceive easily, or if he does he cannot do s
with impunity,
the criticism of those who wish to disparage the honesty
miners
has therefore no force or weight.
In the next place, the occupation of the miner is objectionable
t
nobody. For who, unless he be naturally malevolent and envious, wi
hate the
man who gains wealth as it were from heaven? Or who will hat
a man who to amplify his fortune, adopts a method
which is free fro
reproach? A moneylender, if he demands an excessive interest, incurs
th
hatred of men. If he demands a moderate and lawful rate, so that he is n
injurious
to the public generally and does not impoverish them, he fails
t
become very rich from his business. Further, the gain derived from minin
is not sordid, for how can it
be such, seeing that it is so great, so plentifu
and of so
innocent a nature. A merchant's profits are mean and base whe
he sells counterfeit and
spurious merchandise, or puts far too high a pri
on goods that he
has purchased for little; for this reason the mercha
they not take account of the risk he runs to secure his merchandise. In
truth, those who on this point speak abusively of mining for the sake
of
detracting from its merits, say that in former days men convicted of
crimes
and misdeeds were sentenced to the mines and were worked as
slaves. But
to-day the miners receive pay, and are engaged like other workmen in
the
common trades.
Certainly, if mining is a shameful and discreditable employment for a
gentleman because slaves once worked mines, then agriculture also will
not be
a very creditable employment, because slaves once cultivated the
fields, and
even to-day do so among the Turks; nor will architecture be
considered
honest, because some slaves have been found skilful in that
profession;
nor medicine, because not a few doctors have been slaves;
nor will any other
worthy craft, because men captured by force of arms
have practised it. Yet agriculture, architecture, and medicine are none the less counted
amongst the number of honourable professions; therefore, mining
ought not for this reason to be excluded from them. But suppose we
grant that the hired miners have a sordid employment. We do not mean
by miners only the diggers and other workmen, but also
those skilled in the
mining arts, and those who invest money in mines. Amongst them can be
counted kings, princes, republics, and from these
last the most esteemed
citizens. And finally, we include amongst the overseers of mines the noble
Thucydides, the historian, whom the Athenians placed in charge of the
mines of Thasos.
to work with their own hands
on the works or ore, especially if they them
selves have
contributed to the cost of the mines. Just as it is not undignified
for great men to cultivate their own land. Otherwise the Roman Senate
would not have created Dictator L. Quintius Cincinnatus, as he was at
work in the fields, nor would it have
summoned to the Senate House the
chief men of the State from their
country villas. Similarly, in our day,
Maximilian Cæsar would not have enrolled
Conrad in the ranks of the nobles
known as Counts; Conrad was really
very poor when he served in the mines
of Schneeberg, and for that
reason he was nicknamed the “poor man”; but
is a city in Lorraine, and took his name from
“Luck.”
King Vladislaus have restored to the Assembly of Barons, Tursius, a
citizen of Cracow, who became rich through the mines in that part of
the
kingdom of Hungary which was formerly called Dacia.
common worker in the
mines is vile and abject. For, trained to vigilance
and work by night and day, he has great powers
of endurance when occasion
demands, and easily sustains the fatigues
and duties of a soldier, for he is
accustomed to keep long vigils at
night, to wield iron tools, to dig trenches,
to drive tunnels, to make
machines, and to carry burdens. Therefore, experts
in military affairs prefer the miner, not only to a
commoner from the town,
but even to the rustic.
But to bring this discussion to an end, inasmuch as the chief callings
are those of the moneylender, the soldier, the merchant, the farmer,
and the
miner, I say, inasmuch as usury is odious, while the spoil
cruelly captured
from the possessions of the people innocent of wrong
is wicked in the sight
of God and man, and inasmuch as the calling of
the miner excels in honour
and dignity that of the merchant trading for
lucre, while it is not less noble
though far more profitable than
agriculture, who can fail to realize that
mining is a calling of
peculiar dignity? Certainly, though it is but one of
ten important and excellent methods
of acquiring wealth in an honourable
way, a careful and diligent man
can attain this result in no easier way
than by mining.
END OF BOOK I.
Qualities which the perfect miner should possess
and the arguments which
are urged for and against
the arts of mining and metallurgy, as well
as the people occupied in the industry, I
have sufficiently
discussed in the first Book. Now
I have determined to give more ample information
concerning the
miners.
In the first place, it is indispensable that they
should worship God
with reverence, and that they
understand the matters of which I am
going to speak, and that they
take good care that each individual
performs his duties efficiently and
diligently. It is decreed by Divine Providence that those who know
what they ought
to do and then take care to do it properly, for the
most part meet with
good fortune in all they undertake; on the other
hand, misfortune
overtakes the indolent and those who are careless in
their work. No person indeed can, without great and sustained effort and
labour,
store in his mind the knowledge of every portion of the metallic
arts
which are involved in operating mines. If a man has the means
of paying the necessary expense, he hires as many
men as he needs, and
sends them to the various works. Thus formerly Sosias, the Thracian, sent
into the silver mines a
thousand slaves whom he had hired from the Athenian
Nicias, the son of
NiceratusBut if a man cannot afford the expenditure
he chooses of the various
kinds of mining that work which he himself can
most easily and
efficiently do. Of these kinds, the two most important
are the making prospect trenches
and the washing of the sands of rivers, for
out of these sands are
often collected gold dust, or certain black stones
from which tin is
smelted, or even gems are sometimes found in them; the
trenching
occasionally lays bare at the grass-roots veins which are found rich
in
metals. If therefore by skill or by luck, such sands or veins shall fall
into
his hands, he will be able to establish his fortune without expenditure,
and from poverty rise to wealth. If on the contrary, his hopes are not realised,
then he can desist from
washing or digging.
When anyone, in an endeavour to increase his fortune, meets the
expenditure of a mine alone, it is of great importance that he should
attend
to his works and personally superintend everything that he has
ordered to
be done. For this reason, he should either have his dwelling at the mine,
none neglect their duties, or else he should live in the
neighbourhood, so
that he may frequently inspect his mining works. Then he may send word
by a messenger to the workmen that he is coming
more frequently than
he really intends to come, and so either by his
arrival or by the intimation
of it, he so frightens the workmen that
none of them perform their duties
otherwise than diligently. When he inspects the mines he should praise the
diligent workmen and
occasionally give them rewards, that they and the
others may become
more zealous in their duties; on the other hand, he
should rebuke the
idle and discharge some of them from the mines and
substitute
industrious men in their places. Indeed, the owner should
frequently remain for days and nights in the
mine, which, in truth, is no
habitation for the idle and luxurious; it
is important that the owner who
is diligent in increasing his wealth,
should frequently himself descend into
the mine, and devote some time
to the study of the nature of the veins and
stringers, and should
observe and consider all the methods of working, both
inside and
outside the mine. Nor is this all he ought to do, for sometimes
he should undertake actual
labour, not thereby demeaning himself, but in
order to encourage his
workmen by his own diligence, and to teach
them their art; for that
mine is well conducted in which not only the
foreman, but also the
owner himself, gives instruction as to what ought to
be done. A certain barbarian, according to Xenophon, rightly remarked
to the King
of Persia that “the eye of the master feeds the horse,”
master's watchfulness
in all things is of the utmost importance.
When several share together the expenditure on a mine, it is convenient
and useful to elect from amongst their own number a mine captain, and
also a foreman. For, since men often look after their own interests but
neglect those of
others, they cannot in this case take care of their own without
at the
same time looking after the interests of the others, neither can they
neglect the interests of the others without neglecting their own. But if
no man amongst them be willing or able to undertake and sustain
the bur
dens of these offices, it will be to the common interest to
place them in the
hands of most diligent men. Formerly indeed, these things were looked
after by the mining
prefect
owned the gold mines round Abydos, or as
Midas, who was the owner of
those situated in Mount Bermius, or as
Gyges, or as Alyattes, or as Croesus,
who was the owner of those mines
near a deserted town between Atarnea
and Pergamum
sometimes they were the property of great and illustrious families, as
were
the Athenian mines in Mount Laurion
When a man owns mines but is ignorant of the art of mining, then
it is
advisable that he should share in common with others the expenses,
not
of one only, but of several mines. When one man alone meets the
expense for a long time of a whole mine, if
good fortune bestows on him a
vein abundant in metals, or in other
products, he becomes very wealthy; if,
on the contrary, the mine is
poor and barren, in time he will lose everything
which he has expended
on it. But the man who, in common with others,
has laid out his money on
several mines in a region renowned for its wealth
of metals, rarely
spends it in vain, for fortune usually responds to his
hopes in part. For when out of twelve veins in which he has a joint interest
money he has spent, but also gives a profit besides;
certainly there will
be for him rich and profitable mining, if of the
whole number, three, or four,
or more veins should yield metal. Very similar to this is the advice which
Xenophon gave to the Athenians
when they wished to prospect for new
veins of silver without suffering
loss. “There are,” he said, “ten tribes
of Athenians; if,
therefore, the State assigned an equal number of
slaves to each tribe,
and the tribes participated equally in all the new veins,
undoubtedly
by this method, if a rich vein of silver were found by one tribe,
whatever profit were made from it would assuredly be shared by the
whole
number. And if two, three, or four tribes, or even half the whole number
find
veins, their works would then become more profitable; and it is not
“probable that the work of all the tribes will be
disappointing”
this advice of Xenophon is full of prudence, there is no opportunity
for it
except in free and wealthy States; for those people who are
under the
authority of kings and princes, or are kept in subjection by
tyranny, do not
dare, without permission, to incur such expenditure;
those who are endowed
with little wealth and resources cannot do so on
account of insufficient funds. Moreover, amongst our race it is not customary for Republics to have slaves
whom they can hire out for the benefit of the people
adays those who
are in authority administer the funds for mining in the name
of the
State, not unlike private individuals.
Some owners prefer to buy shares
rather than to be troubled themselves to
search for the veins; these men
employ an easier and less uncertain
method of increasing their property. Although their hopes in the shares of one or another mine may be frustrated,
the buyers of shares should not abandon the rest of the mines, for all
the
money expended will be recovered with interest from some other
mine. They should not buy only high priced shares in those mines producing metals,
nor should they buy too many in neighbouring mines where metal has not
yet been found, lest, should fortune not respond, they may be exhausted
by
their losses and have nothing with which they may meet their
expenses
or buy other shares which may replace their losses. This calamity over
takes those who wish to grow suddenly rich from
mines, and instead, they
become very much poorer than before. So then, in the buying of shares,
as in other matters, there should be a
certain limit of expenditure which
miners should set themselves, lest
blinded by the desire for excessive wealth,
they throw all their money
away. Moreover, a prudent owner, before he
buys shares, ought to go to the
mine and carefully examine the nature of the
vein, for it is very
important that he should be on his guard lest fraudulent
sellers of
shares should deceive him. Investors in shares may perhaps
become less wealthy, but they are more
certain of some gain than those who
mine for metals at their own
expense, as they are more cautious in trusting
to fortune. Neither ought miners to be altogether distrustful of fortune, as
we see
some are, who as soon as the shares of any mine begin to go up in
There are some people who wash over the dumps from exhausted and
abandoned mines, and those dumps which are derived from the drains of
tunnels; and others who smelt the old slags; from all of which they
make an
ample return.
Now a miner, before he begins to mine the veins, must consider seven
things, namely:—the situation, the conditions, the water, the
roads, the
climate, the right of ownership, and the neighbours. There are four kinds
of situations—mountain, hill, valley, and
plain. Of these four, the
first two are the most easily mined, because in them
tunnels can be
driven to drain off the water, which often makes mining
operations very
laborious, if it does not stop them altogether. The last two kinds of
ground are more troublesome, especially because
tunnels cannot be driven
in such places. Nevertheless, a prudent miner considers all these four
sorts of
localities in the region in which he happens to be, and he searches for
veins in those places where some torrent or other agency has removed
and
swept the soil away; yet he need not prospect everywhere, but since
there
is a great variety, both in mountains and in the three other
kinds of
localities, he always selects from them those which will give
him the best
chance of obtaining wealth.
In the first place, mountains differ greatly in position, some being
situated in even and level plains, while others are found in broken and
elevated regions, and others again seem to be piled up, one mountain
upon
another. The wise miner does not mine in mountains which are situated on
open
plains, neither does he dig in those which are placed on the summits of
mountainous regions, unless by some chance the veins in those mountains
have been denuded of their surface covering, and abounding in metals
and
other products, are exposed plainly to his notice,—for with
regard to what
I have already said more than once, and though I never
repeat it again,
I wish to emphasize this exception as to the
localities which should
not be selected. All districts do not possess a great number of mountains
crowded
together; some have but one, others two, others three, or perhaps
a few
more. In some places there are plains lying between them; in others
the
mountains are joined together or separated only by narrow valleys. The miner should not dig in those solitary mountains, dispersed through
the plains and open regions, but only in those which are connected and
joined with others. Then again, since mountains differ in size, some being
very large,
others of medium height, and others more like hills than
mountains, the
miner rarely digs in the largest or the smallest of them,
but generally
only in those of medium size. Moreover, mountains have a
great variety of shapes; for with some the
slopes rise gradually, while
others, on the contrary, are all
precipitous; in some others the slopes are
gradual on one side, and on
the other sides precipitous; some are drawn
out in length; some are
gently curved; others assume different
shapes. But the miner may dig in all parts of them, except where there
are
precipices, and he should not neglect even these latter if metallic veins
There are just as great differences in hills as
there are in mountains,
yet the miner does not dig except in those situated
in mountainous
districts, and even very rarely in those. It is however very
little to be wondered at that the hill in the Island
of Lemnos was excavated,
for the whole is of a reddish-yellow colour,
which furnishes for the inhabit
ants that valuable clay so
especially beneficial to mankindIn like
manner, other hills are excavated if chalk or other varieties of
earth are
exposed, but these are not prospected for.
There are likewise many varieties of valleys and plains.
One kind is
enclosed on the sides with its outlet and entrance open;
another has either
its entrance or its outlet open and the rest of it
is closed in; both of these are
properly called valleys. There is a third variety which is surrounded on all
sides by mountains,
and these are called Some valleys again,
have recesses, and others have none; one is wide,
another narrow; one
is long, another short; yet another kind is not
higher than the neighbouring
plain, and others are lower than the
surrounding flat country. But the
miner does not dig in those surrounded on all sides by
mountains, nor in those
that are open, unless there be a low plain
close at hand, or unless a vein
of metal descending from the mountains
should extend into the valley. Plains differ from one another, one being situated at low elevation,
and
others higher, one being level and another with a slight incline. The
miner should never excavate the low-lying plain, nor one which is
perfectly
level, unless it be in some mountain, and rarely should he
mine in the other
kinds of plains.
With regard to the conditions of the locality the miner should
not
contemplate mining without considering whether the place be
covered
with trees or is bare. If it be a wooded place, he who digs there
has this advantage, besides
others, that there will be an abundant supply of
wood for his
underground timbering, his machinery, buildings, smelting,
and other
necessities. If there is no forest he should not mine there unless
there is a river
near, by which he can carry down the timber. Yet wherever
there is a hope that pure gold or gems may be found, the
ground can
be turned up, even though there is no forest, because the
gems need only
to be polished and the gold to be purified. Therefore the inhabitants of
hot regions obtain these substances from
rough and sandy places, where
sometimes there are not even shrubs, much
less woods.
The miner should next consider the locality, as to whether it has a
perpetual supply of running water, or whether it is always devoid of
water
except when a torrent supplied by rains flows down from the
summits of the
mountains. The place that Nature has provided with a river or stream can
can be carried through wooden pipes to baths in
dwelling-houses; it may
be carried to the works, where the metals are
smelted; and finally, if the
conditions of the place will allow it, the
water can be diverted into the
tunnels, so that it may turn the
underground machinery. Yet on the other
hand, to convey a constant supply of water by
artificial means to mines
where Nature has denied it access, or to
convey the ore to the stream,
increases the expense greatly, in
proportion to the distance the mines are
away from the river.
The miner also should consider whether the roads from the neighbouring
regions to the mines are good or bad, short or long. For since a region
which is abundant in mining products very often
yields no agricultural
produce, and the necessaries of life for the
workmen and others must all be
imported, a bad and long road occasions
much loss and trouble with
porters and carriers, and this increases the
cost of goods brought in, which,
therefore, must be sold at high
prices. This injures not so much the work
men as the masters; since on
account of the high price of goods, the work
men are not content
with the wages customary for their labour, nor can
they be, and they
ask higher pay from the owners. And if the owners
refuse, the men will not work any longer in the mines
but will go elsewhere. Although districts which yield metals and other mineral products are
generally healthy, because, being often situated on high and lofty
ground,
they are fanned by every wind, yet sometimes they are
unhealthy, as has
been related in my other book, which is called
“
Effluunt ex
Terra.
even if they are very productive, when he
perceives unmistakable signs
of pestilence. For if a man mines in an unhealthy region he may be alive
one hour and
dead the next.
Then, the miner should make careful and thorough investigation
con
cerning the lord of the locality, whether he be a just and good
man or a
tyrant, for the latter oppresses men by force of his
authority, and seizes
their possessions for himself; but the former
governs justly and lawfully
and serves the common good. The miner should not start mining opera
tions in a district which is
oppressed by a tyrant, but should carefully
consider if in the vicinity
there is any other locality suitable for mining and
make up his mind if
the overlord there be friendly or inimical. If he be
inimical the mine will be rendered unsafe through hostile
attacks, in one of
which all of the gold or silver, or other mineral
products, laboriously col
lected with much cost, will be taken away
from the owner and his workmen
will be struck with terror; overcome by
fear, they will hastily fly, to free
themselves from the danger to
which they are exposed. In this case, not
only are the fortunes of the miner in the greatest
peril but his very life is
in jeopardy, for which reason he should not
mine in such places.
Since several miners usually come to mine the veins in one locality, a
settlement generally springs up, for the miner who began first cannot
keep
it exclusively for himself. The
the cross veins, to others the inclined
veins. If the man who first starts
work finds the vein to be metal-bearing or
yielding other mining products,
it will not be to his advantage to
cease work because the neighbourhood may
be evil, but he will guard and
defend his rights both by arms and by the law. When the
of a good miner to keep within his bounds, and of
a prudent one to repel
encroachments of his neighbours by the help of
the law. But this is enough
about the neighbourhood.
The miner should try to obtain a mine, to which access is not difficult,
in a mountainous region, gently sloping, wooded, healthy, safe, and not
far
distant from a river or stream by means of which he may convey his
mining products to be washed and smelted. This indeed, is the best
position. As for the others, the nearer they approximate to this position the
better they are; the further removed, the worse.
Now I will discuss that kind of minerals for which it is not necessary
to dig, because the force of water carries them out of the veins. Of these
there are two kinds, minerals—and their fragmentsWhen
there are springs at the outcrop of the veins from which, as I have
already said,
the above-mentioned products are emitted, the miner
should consider these
first, to see whether there are metals or gems
mixed with the sand, or whether
the waters discharged are filled with
juices. In case metals or gems have
settled in the pool of the spring, not only
should the sand from it be
washed, but also that from the streams which
flow from these springs, and
even from the river itself into which they
again discharge. If the springs dis
charge water containing some juice, this also
should be collected; the further
such a stream has flowed from the
source, the more it receives plain water and
the more diluted does it
become, and so much the more deficient in strength. If the stream receives no water of another kind, or scarcely any, not only
the rivers, but likewise the lakes which receive these waters, are of
the same
nature as the springs, and serve the same uses; of this kind
is the lake
which the Hebrews call the Dead Sea, and which is quite
full of bituminous
fluidsBut I must return to the subject of the sands.
Springs may discharge their waters into a sea, a lake, a marsh, a river,
or a stream; but the sand of the sea-shore is rarely washed, for
although the
water flowing down from the springs into the sea carries
some metals or
gems with it, yet these substances can scarcely ever be
reclaimed, because
they are dispersed through the immense body of
waters and mixed up with
sink down into
the depths of the sea. For the same reasons, the sands of
lakes can very rarely be washed
successfully, even though the streams rising
from the mountains pour
their whole volume of water into them. The
particles of metals and gems from the springs are very rarely
carried into the
marshes, which are generally in level and open places. Therefore, the
miner, in the first place, washes the sand of the spring,
then of the stream
which flows from it, then finally, that of the river
into which the stream
discharges. It is not worth the trouble to wash the sands of a large
river which is
on a level plain at a distance from the mountains. Where
several springs carrying metals discharge their waters into one
river, there
is more hope of productive results from washing. The miner does not
neglect even the sands of the streams in which
excavated ores have been
washed.
The waters of springs taste according to the juice they contain, and
they differ greatly in this respect. There are six kinds of these tastes which
the worker
which shows that salt may be obtained by evaporation;
the nitrous, which
indicates soda; the aluminous kind, which indicates
alum; the vitrioline,
which indicates vitriol; the sulphurous kind,
which indicates sulphur;
and as for the bituminous juice, out of which
bitumen is melted down, the
colour itself proclaims it to the worker
who is evaporating it. The sea
water however, is similar to that of salt springs, and may
be drawn into
low-lying pits, and, evaporated by the heat of the sun,
changes of
itself into salt; similarly the water of some salt-lakes
turns to salt when dried
by the heat of summer. Therefore an industrious and diligent man observes
and makes use of
these things and thus contributes something to the
common welfare.
The strength of the sea condenses the liquid bitumen which flows into
it
from hidden springs, into amber and jet, as I have described already in
my books “The sea, with certain
reason the search for
amber demands as much care as does that for coral.
Moreover, it is necessary that those who wash the sand or evaporate
the
water from the springs, should be careful to learn the nature of the
locality, its roads, its salubrity, its overlord, and the neighbours,
lest on
account of difficulties in the conduct of their business they
become either
impoverished by exhaustive expenditure, or their goods
and lives are
imperilled. But enough about this.
The miner, after he has selected out of many places one particular spot
adapted by Nature for mining, bestows much labour and attention on the
veins. These have either been stripped bare of their covering by chance
and
thus lie exposed to our view, or lying deeply hidden and concealed they
are found after close search; the latter is more usual, the former more
rarely happens, and both of these occurrences must be explained. There
is more than one force which can lay bare the veins unaided by the
industry
or toil of man; since either a torrent might strip off the
surface, which hap
pened in the case of the silver mines of
Freiberg (concerning which I have
may be exposed through the
force of the wind, when it uproots and destroys
the trees which have
grown over the veins; or by the breaking away of the
rocks; or by
long-continued heavy rains tearing away the mountain; or by
an
earthquake; or by a lightning flash; or by a snowslide; or by the
violence of the winds: “Of such a nature are the rocks hurled
down from
the mountains by the force of the winds aided by the ravages
of time.” Or
the plough may uncover the veins, for Justin relates
in his history that
nuggets of gold had been turned up in Galicia by
the plough; or this may
occur through a fire in the forest, as Diodorus
Siculus tells us happened in the
silver mines in Spain; and that saying
of Posidonius is appropriate enough:
“The earth violently moved
by the fires consuming the forest sends forth new
products, namely,
gold and silver.”And indeed, Lucretius has ex
plained the same thing more fully in
the following lines: “Copper and gold
and iron were discovered,
and at the same time weighty silver and the sub
stance of lead,
when fire had burned up vast forests on the great hills, either
by a
discharge of heaven's lightning, or else because, when men were waging
war with one another, forest fires had carried fire among the enemy in
order to
strike terror to them, or because, attracted by the goodness
of the soil, they
wished to clear rich fields and bring the country
into pasture, or else to destroy
wild beasts and enrich themselves with
the game; for hunting with pitfalls
and with fire came into use before
the practice of enclosing the wood with
toils and rousing the game with
dogs. Whatever the fact is, from
crackling from
their very roots, and had thoroughly baked the earth with
fire, there
would run from the boiling veins and collect into the hollows of the
grounds a stream of silver and gold, as well as of copper and
lead.”
yet the
poet considers that the veins are not laid bare in the first instance
so much by this kind of fire, but rather that all mining had its
origin in this. And lastly, some other force may by chance disclose the
veins, for a
horse, if this tale can be believed, disclosed the lead veins at
Goslar
by a blow from his hoofBy such methods as these does fortune
disclose the veins to us.
But by skill we can also investigate hidden and concealed veins, by
observing in the first place the bubbling waters of springs, which
cannot be
very far distant from the veins because the source of the
water is from
them; secondly, by examining the fragments of the veins
which the torrents
break off from the earth, for after a long time some
of these fragments are
again buried in the ground. Fragments of this kind lying about on the
ground, if they are rubbed
smooth, are a long distance from the veins,
because the torrent, which
broke them from the vein, polished them while
it rolled them a long
distance; but if they are fixed in the ground, or if
they are rough,
they are nearer to the veins. The soil also should be con
sidered, for this is often the cause of
veins being buried more or less deeply
under the earth; in this case
the fragments protrude more or less widely
apart, and miners are wont
to call the veins discovered in this manner
“
Further, we search for the veins by observing the hoar-frosts,
which
whiten all herbage except that growing over the veins, because the
veins emit a warm and dry exhalation which hinders the freezing of the
moisture, for which reason such plants appear rather wet than whitened
by
the frost. This may be observed in all cold places before the grass has grown
to
its full size, as in the months of April and May; or when the late crop of
September. Therefore in places where the grass has a dampness that is not
con
gealed into frost, there is a vein beneath: also if the
exhalation be excessively
hot, the soil will produce only small and
pale-coloured plants. Lastly, there
are trees whose foliage in spring time has a bluish or
leaden tint, the upper
branches more especially being tinged with black
or with any other unnatural
colour, the trunks cleft in two, and the
branches black or discoloured. These phenomena are caused by the intensely hot and dry exhalations
which do not spare even the roots, but scorching them, render the trees
sickly; wherefore the wind will more frequently uproot trees of this
kind
than any others. Verily the veins do emit this exhalation.
Therefore, in a
place where there is a multitude of trees, if a long row
of them at an unusual
time lose their verdure and become black or
discoloured, and frequently fall
by the violence of the wind, beneath
this spot there is a vein. Likewise
along a course where a vein extends, there grows a certain herb
or fungus
which is absent from the adjacent space, or sometimes even
from the neigh
bourhood of the veins. By these signs of Nature a vein can be discovered.
There are many great contentions between miners concerning the forked
twig
others deny it. Some of those who manipulate and use the twig, first cut
a fork from a
hazel bush with a knife, for this bush they consider more
efficacious
than any other for revealing the veins, especially if the hazel Others use a different kind of twig for each metal,
when they are
seeking to discover the veins, for they employ hazel twigs
for veins of
silver; ash twigs for copper; pitch pine for lead and especially
tin,
and rods made of iron and steel for gold. All alike grasp the forks of
the twig with their hands, clenching their
fists, it being necessary that the
clenched fingers should be held
toward the sky in order that the twig should
be raised at that end
where the two branches meet. Then they wander
hither and thither at random through mountainous
regions. It is said
that the moment they place their feet on a vein the twig
immediately turns
and twists, and so by its action discloses the vein;
when they move
their feet again and go away from that spot the twig
becomes once more
immobile.
The truth is, they assert, the movement of the twig is caused by the
power of the veins, and sometimes this is so great that the branches of
trees
growing near a vein are deflected toward it. On the other hand, those
who say that the twig is of no use to good and
serious men, also deny that
the motion is due to the power of the
veins, because the twigs will not move
for everybody, but only for
those who employ incantations and craft. More
over, they deny the power of a vein to draw to itself the
branches of trees,
but they say that the warm and dry exhalations cause
these contortions. Those who advocate the use of the twig make this reply to these objections:
when one of the miners or some other person holds the twig in his
hands,
and it is not turned by the force of a vein, this is due to some
peculiarity
of the individual, which hinders and impedes the power of
the vein, for since
the power of the vein in turning and twisting the
twig may be not unlike
that of a magnet attracting and drawing iron
toward itself, this hidden
quality of a man weakens and breaks the
force, just the same as garlic
weakens and overcomes the strength of a
magnet. For a magnet smeared
with garlic juice cannot attract iron; nor does it
attract the latter when
rusty. Further, concerning the handling of the twig, they warn us that
we
should not press the fingers together too lightly, nor clench them too
firmly, for if the twig is held lightly they say that it will fall
before the force
of the vein can turn it; if however, it is grasped too
firmly the force of the
hands resists the force of the veins and
counteracts it. Therefore, they
consider that five things are necessary to insure that
the twig shall serve
its purpose: of these the first is the size of the
twig, for the force of the
veins cannot turn too large a stick;
secondly, there is the shape of the twig,
which must be forked or the
vein cannot turn it; thirdly, the power of the
vein which has the
nature to turn it; fourthly, the manipulation of the twig;
fifthly, the
absence of impeding peculiarities. These advocates of the twig
sum up their conclusions as follows: if the
rod does not move for every
body, it is due to unskilled
manipulation or to the impeding peculiarities
of the man which oppose
and resist the force of the veins, as we said above,
and those who
search for veins by means of the twig need not necessarily make
incantations, but it is sufficient that they handle it suitably and are
devoid
of impeding power; therefore, the twig may be of use to good and
serious
A—TWIG. B—TRENCH.
men in discovering veins. With regard to deflection of branches of trees
they say nothing and
adhere to their opinion.
Since this matter remains in dispute and causes much dissention
amongst
miners, I consider it ought to be examined on its own merits. The
wizards, who also make use of rings, mirrors and crystals, seek for
veins
with a divining rod shaped like a fork; but its shape makes no
difference
in the matter,—it might be straight or of some other
form—for it is not
the form of the twig that matters, but the
wizard's incantations
which it would not become me to repeat, neither
do I wish to do so. The
Ancients, by means of the divining rod, not only procured those
things neces
sary for a livelihood or for luxury, but they were
also able to alter the forms
of things by it; as when the magicians
changed the rods of the Egyptians
into serpents, as the writings of the
Hebrews relate
Minerva with a divining rod turned the aged Ulysses suddenly into a
youth,
and then restored him back again to old age; Circe also changed
Ulysses'
companions into beasts, but afterward gave them back again
their human
formTherefore it seems that the
divining rod passed to the mines from its
impure origin with the magicians. Then when good men shrank with horror from the incantations and rejected
them, the twig was retained by the unsophisticated common miners, and
in searching for new veins some traces of these ancient usages
remain.
But since truly the twigs of the miners do move, albeit they do not
generally use incantations, some say this movement is caused by the
power of the veins, others say that it depends on the manipulation, and
still others think that the movement is due to both these causes. But, in
truth, all those objects which are endowed with the power of
attraction
do not twist things in circles, but attract them directly to
themselves; for
instance, the magnet does not turn the iron, but draws
it directly to itself,
and amber rubbed until it is warm does not bend
straws about, but simply
draws them to itself. If the power of the veins were of a similar nature to
that of the magnet
and the amber, the twig would not so much twist as
move once only, in a
semi-circle, and be drawn directly to the vein, and unless
the strength
of the man who holds the twig were to resist and oppose the
force of
the vein, the twig would be brought to the ground; wherefore,
since
this is not the case, it must necessarily follow that the manipulation
is the cause of the twig's twisting motion. It is a conspicuous fact that
these cunning manipulators do not use a
straight twig, but a forked one
cut from a hazel bush, or from some
other wood equally flexible, so that if it
be held in the hands, as
they are accustomed to hold it, it turns in a circle
for any man
wherever he stands. Nor is it strange that the twig does not
turn when held by the
inexperienced, because they either grasp the forks of
the twig too
tightly or hold them too loosely. Nevertheless, these things
give rise to the faith among common miners
that veins are discovered by
the use of twigs, because whilst using
these they do accidentally discover
some; but it more often happens
that they lose their labour, and although
they might discover a vein,
they become none the less exhausted in
digging useless trenches than do
the miners who prospect in an unfortunate
locality. Therefore a miner, since we think he ought to be a good and
serious man,
should not make use of an enchanted twig, because if he is
prudent and
skilled in the natural signs, he understands that a forked stick
is of
no use to him, for as I have said before, there are the natural
indica
tions of the veins which he can see for himself without the
help of twigs. So if Nature or chance should indicate a locality suitable for mining, the
miner should dig his trenches there; if no vein appears he must dig
numerous trenches until he discovers an outcrop of a vein.
force or other reveals it,
or sometimes it is discovered by a shaft or a tunnel
on a
The veins after they have been discovered, and likewise the shafts and
tunnels, have names given them, either from their discoverers, as in
the
case at Annaberg of the vein called “Kölergang,”
because a charcoal
burner discovered it; or from their owners, as the
Geyer, in Joachimstal,
because part of the same belonged to Geyer; or
from their products,
as the “Pleygang” from lead, or the
“Bissmutisch” at Schneeberg from
bismuth
the torrent by which they were laid bare in the
valley of Joachim. More
often the first discoverers give the names either of persons, as
those of
German Kaiser, Apollo, Janus; or the name of an animal, as
that of lion,
bear, ram, or cow; or of things inanimate, as
“silver chest” or “ox stalls”;
or of something
ridiculous, as “glutton's nightshade”; or finally, for the sake
of a good omen, they call it after the Deity. In ancient times they
followed the same custom and gave names to the
veins, shafts and tunnels,
as we read in Pliny: “It is wonderful
that the shafts begun by Hannibal in
Spain are still worked, their
names being derived from their discoverers. One of these at the present day, called Baebelo, furnished Hannibal with
three hundred pounds weight (of silver) per day.”
END OF BOOK II.
Previously I have given much information
concerning the miners, also I
have discussed the
choice of localities for mining. for washing sands,
and for evaporating waters; further, I described
the method of searching for veins. With such
matters I was occupied in the second book; now I
come to
the third book, which is about veins and
stringers, and the seams in
the rocksThe
term “vein” is sometimes used to indicate
in the earth, but
very often elsewhere by this name I have described that
which may be
put in vessels
these words, for by them I mean to designate any
mineral substances which
the earth keeps hidden within her own deep
receptacles.
First I will speak of the veins, which, in depth, width, and length, differ
very much one from another. Those of one variety descend from the surface
of the earth to its lowest
depths, which on account of this characteristic,
I am accustomed to
call “
A. C.—THE MOUNTAIN. B—
Another kind, unlike the
of the earth nor
descend, but lying under the ground, expand over a large
area; and on
that account I call them “
Another occupies a large extent of space in length and width;
there
fore I usually call it “
lation of some certain kind of mineral, as I have
described in the book It occasionally happens,
though it is unusual and rare, that several
accumulations of this kind are
found in one place, each one or more
fathoms in depth and four or five in When
the excavation of these accumulations begins, they at first appear
in the
shape of a disc; then they open out wider; finally from each of
such
A, B, C, D—THE MOUNTAIN. E, F, G, H, I, K—
accumulations is usually
formed a “
A—
B—
C—ANOTHER
A & B—
C—
D & E—OTHER
The space between two veins is called an
between the veins, if it is between
ground. If, however, it lies between
in sight, and the
remainder is hidden.
them are one fathom
wide, some are two cubits, others one cubit; others again
are a foot
wide, and some only half a foot; all of which our miners call wide
veins. Others on the contrary, are only a palm wide, others three digits,
But in other places where there are
very wide veins, the widths of a
cubit, or a foot, or half a foot, are said to be
narrow; at Cremnitz,
for instance, there is a certain vein which measures
in one place
fifteen fathoms in width, in another eighteen, and in another
twenty;
the truth of this statement is vouched for by the inhabitants.
A—WIDE
B—NARROW
thick, others two, or
even more; some are a cubit thick, some a foot, some
only half a foot;
and all these are usually called thick veins. Some on the
other hand, are but a palm thick, some three digits, some
two, some one;
these are called thin veins.
A—THIN
B—THICK
A, B, C—VEIN. D, E, F—SEAMS IN THE ROCK (
Others, on the other hand, run from west to east.
A, B, C—VEIN. D, E, F—
Others run from south to north.
A, B, C—VEIN. D, E, F—
Others, on the contrary, run from north to south.
A, B, C—VEIN. D, E, F—
The seams in the rocks indicate to us whether a vein runs from the
east
or from the west. For instance, if the rock seams incline toward the
westward as they
descend into the earth, the vein is said to run from east
to west; if
they incline toward the east, the vein is said to run from west
to
east; in a similar manner, we determine from the rock seams whether
the
veins run north or south.
Now miners divide each quarter of the earth into six divisions; and by
this method they apportion the earth into twenty-four directions, which
they
divide into two parts of twelve each. The instrument which indicates these
directions is thus constructed. First a circle is made; then at equal
intervals on one half portion of
it right through to the other, twelve
straight lines called by the
Greeks
are drawn through a central point which the Greeks call
the circle is thus divided
into twenty-four divisions, all being of an equal
size. Then, within the circle are inscribed three other circles, the
outer
most of which has cross-lines dividing it into twenty-four
equal parts; the
space between it and the next circle contains two sets
of twelve numbers,
inscribed on the lines called
“diameters”; while within the innermost circle
it is
hollowed out to contain a magnetic needleThe needle lies directly
XII is inscribed at
both ends.
When the needle which is governed by the magnet points directly
from the
north to the south, the number XII at its tail, which is
forked,
signifies the north, that number XII which is at its point indicates
the south. The sign VI superior indicates the east, and VI inferior the
west. Further, between each two cardinal points there are always
five others
which are not so important. The first two of these directions
are called the prior directions; the
last two are called the posterior, and
the fifth direction lies
immediately between the former and the latter; it
is halved, and one
half is attributed to one cardinal point and one half to the
other. For example, between the northern number XII and the eastern
number VI,
are points numbered I, II, III, IV, V, of which I and
directions lying toward the north, and III is assigned, half to the
north and
half to the east.
One who wishes to know the direction of the veins underground, places
over the vein the instrument just described; and the needle, as soon as
it
becomes quiet, will indicate the course of the vein. That is, if the vein
proceeds from VI to VI, it either runs from east to
west, or from west to
east; but whether it be the former or the latter,
is clearly shown by the
seams in the rocks. If the vein proceeds along the line which is between V
and VI toward the
opposite direction, it runs from between the fifth and
sixth divisions
of east to the west, or from between the fifth and sixth
divisions of
west to the east; and again, whether it is the one or the other
is
clearly shown by the seams in the rocks. In a similar manner we
determine the other directions.
Now miners reckon as many points as the sailors do in reckoning up
the
number of the winds. Not only is this done to-day in this country, but
it was also done by
the Romans who in olden times gave the winds partly
Latin names and
partly names borrowed from the Greeks. Any miner who
pleases may therefore call the directions of the veins by
the names of the
winds. There are four principal winds, as there are four cardinal points:
the
which blows from the
west; the latter is called by the Greeks
the former
and
opposed to it is the
called
to the number of twenty, as there are directions, for between each two
principal winds there are always five subordinate ones. Between the
or the Bird
wind, which has the first place next to the
comes
comes
The Greeks have
given these names to all of these, with the exception of
say this is the same
as the Greeks called
wind)
and the
one of these five; after that
comes
of
In a similar
manner, between
wind), first to the
right of
and lastly
these, except that of
who do not distinguish the winds by so exact a plan, assert that the
wind
which the Greeks called
first to the right of
lastly
do not consider the winds to be in so
great a multitude, but say there are
but twelve winds in all, or at the
most fourteen, assert that the wind called
by
the Greeks For our
purpose it is not only useful to adopt this large number of
winds, but even
to double it, as the German sailors do. They always reckon that between
each two there is one in the centre
taken from both. By this method we
the winds. For instance, if a vein runs from VI east to VI west, it is said
to
proceed from
which proceeds from between V and VI of the
east to between V and VI
west is said to proceed out of the middle of
are similarly designated. The miner, on account of the natural properties
of a magnet, by which
the needle points to the south, must fix the instru
ment already
described so that east is to the left and west to the right.
In a similar way to
lateral directions, and we are able
to understand from the seams in the
rocks in which direction they
extend into the ground. For if these incline
toward the west in depth, the vein is said to
extend from east to west;
if on the contrary, they incline toward the
east, the vein is said to go from
west to east. In the same way, from the rock seams we can determine
veins running
south and north, or the reverse, and likewise to the
subordinate
directions and their intermediates.
A, B—
C—
Further, as regards the question of direction of a
runs straight from one
quarter of the earth to that quarter which is opposite,
while another
one runs in a curve, in which case it may happen that a vein
proceeding
from the east does not turn to the quarter opposite, which is the
west,
but twists itself and turns to the south or the north.
A—STRAIGHT
B—CURVED
Similarly some
some are
curved.
A—HORIZONTAL
B—INCLINED
C—CURVED
Also the veins which we call
they descend into
the depths of the earth; for some are vertical (A), some are
inclined
and sloping (B), others crooked
Moreover,
the kind of locality through
which they pass, for some extend along the
slopes of mountains or hills
(A-C) and do not descend down the sides.
Other
or hill descend the slope (A)
to the hollow or valley (B), and they again ascend
the slope or the
side of the mountain or hill opposite (C)
Other
extend out into the plain (B).
Some veins run straight along on the plateaux, the hills, or plains.
A—MOUNTAINOUS PLAIN. B—
A—PRINCIPAL VEIN. B—TRANSVERSE VEIN. C—VEIN CUTTING
PRINCIPAL ONE
OBLIQUELY.
In the next place,
which they
intersect, since one may cross through a second transversely, or
one
may cross another one obliquely as if cutting it in two.
If a vein which cuts through another principal one obliquely be the
harder of the two, it penetrates right through it, just as a wedge of
beech or
iron can be driven through soft wood by means of a tool. If it be softer, the
principal vein either drags the soft one with it
for a distance of three feet, or
perhaps one, two, three, or several
fathoms, or else throws it forward along
the principal vein; but this
latter happens very rarely. But that the vein
which cuts the principal one is the same vein on both
sides, is shown by its
having the same character in its foot walls and
hanging walls.
A—PRINCIPAL VEIN. B—VEIN WHICH CUTS A OBLIQUELY. C—PART
CARRIED AWAY.
D—THAT PART WHICH HAS BEEN CARRIED FORWARD.
Sometimes
more outcropping veins
one is made, if they are not far distant from each other,
and the one dips
into the other, or if each dips toward the other, and
they thus join when they
have descended in depth. In exactly the same way, out of three or more
veins, one may be formed
in depth.
A, B—TWO VEINS DESCEND INCLINED AND DIP TOWARD EACH OTHER.
C—JUNCTION. LIKEWISE TWO VEINS. D—INDICATES ONE DESCENDING
VERTICALLY.
E—MARKS THE OTHER DESCENDING INCLINED, WHICH DIPS
TOWARD D. F—THEIR JUNCTIO
However, such a junction of veins sometimes disunites and in this
way it
happens that the vein which was the right-hand vein becomes
the left;
and again, the one which was on the left becomes the right.
Furthermore, one vein may be split and divided into parts by some hard
rock resembling a beak, or stringers in soft rock may sunder the vein
and
make two or more. These sometimes join together again and sometimes
remain divided.
A, B—VEINS DIVIDING. C—THE SAME JOINING.
Whether a vein is separating from or uniting with another can be
deter
mined only from the seams in the rocks. For example, if a principal
vein runs from the east to the west, the
rock seams descend in depth
likewise from the east toward the west, and
the associated vein which
joins with the principal vein, whether it
runs from the south or the north,
has its rock seams extending in the
same way as its own, and they do not
conform with the seams in the rock
of the principal vein—which remain
the same after the
junction—unless the associated vein proceeds in the same
direction as the principal vein. In that case we name the broader vein the
principal one, and the
narrower the associated vein. But if the principal
vein splits, the rock seams which belong
respectively to the parts, keep
the same course when descending in
depth as those of the principal vein.
But enough of
Now
we come to A
or join with it, or it may be cut by a
A, C—
B—
D, E—
dilatata F—
G—
H, I—ITS DIVIDED PARTS. K—
Finally, a
“head” (
is said to be its
“beginning,” that in which it terminates the “end.”
Its
“head”
which is hidden in the earth. But miners have no need to seek the
“beginning” of veins, as
formerly the kings of Egypt sought for the source
of the Nile, but it
is enough for them to discover some other part of the vein
and to
recognise its direction, for seldom can either the “beginning”
or the
“end” be found. The direction in which the head of the vein comes into
the light, or the
direction toward which the tail extends, is indicated by its
footwall
and hangingwall. The latter is said to hang, and the former to lie.
The vein rests on the footwall, and the hangingwall overhangs it; thus,
when we descend a shaft, the part to which we turn the face is the
foot
wall and seat of the vein, that to which we turn the back is
the hanging
wall. Also in another way, the head accords with the footwall and the tail
with the hangingwall, for if the footwall is toward the south, the vein
extends its head into the light toward the south; and the hangingwall,
because it is always opposite to the footwall, is then toward the
north. Consequently the vein extends its tail toward the north if it is an inclined
Similarly, we can determine with regard to east and west
and the
subordinate and their intermediate directions. A
which
descends into the earth may be either vertical, inclined, or crooked,
the footwall of an inclined vein is easily distinguished from the
hangingwall,
but it is not so with a vertical vein; and again, the
footwall of a crooked
vein is inverted and changed into the
hangingwall, and contrariwise the
hangingwall is twisted into the
footwall, but very many of these crooked
veins may be turned back to
vertical or inclined ones.
A—THE “BEGINNING” (
D—THE “TAIL” (
A
of
the “head” and “tail” it has two sides.
A—THE “BEGINNING.” B—THE “END.” C,
D—THE “SIDES.”
A—THE “BEGINNING.” B—THE “END.”
C—THE “HEAD.” D—THE “TAIL.”
E—TRANSVERSE VEIN.
A
“tail,” just as a Moreover, a
a
Stringers (
versae, fibrae
obliquae
fibrae dilatatae, The
the vein; the
with the vein itself; the
through it; but the
found associated
with a vein.
The
other stringers, but lies on
the vein, as it were, from the surface to the
hangingwall or footwall,
from which it is named
In truth, as to direction, junctions, and divisions, the stringers are not
different from the veins.
A, B—VEINS. C—TRANSVERSE STRINGER. D—OBLIQUE STRINGER.
E—ASSOCIATED STRINGER. F—
A—VEIN. B—
FROM THE FOOTWALL.
Lastly, the seams, which are the very finest stringers (
the rock, and occur
sometimes frequently, sometimes rarely. From
whatever direction the vein comes, its seams always turn their
heads
toward the light in the same direction. But, while the seams usually run
from one point of the compass to
another immediately opposite it, as
for instance, from east to west, if
hard stringers divert them, it may
happen that these very seams, which
before were running from east to
west, then contrariwise proceed from
west to east, and the direction of
the rocks is thus inverted. In such a case, the direction of the veins is
judged, not by the
direction of the seams which occur rarely, but by those
which
constantly recur.
A—SEAMS WHICH PROCEED FROM THE EAST. B—THE INVERSE.
Both veins or stringers may be solid or drusy, or barren of minerals,
or
pervious to water. Solid veins contain no water and very little air.
The
drusy veins rarely contain water; they often contain air. Those which
are barren of minerals often carry water. Solid veins and stringers con
sist sometimes of hard materials,
sometimes of soft, and sometimes of a
kind of medium between the
two.
A—SOLID VEIN. B—SOLID STRINGER. C—CAVERNOUS VEIN.
D—CAVERNOUS
STRINGER. E—BARREN VEIN. F—BARREN
STRINGER.
But to return to veins.
A great number of miners consider
best veins in depth are those which run from the VI or VII
direction of the
east to the VI or VII direction of the west, through a
mountain slope which
inclines to the north; and whose hangingwalls are
in the south, and whose
footwalls are in the north, and which have
their heads rising to the north,
as explained before, always like the
footwall, and finally, whose rock
seams turn their heads to the east. And the veins which are the next
of the west to the VI
or VII direction of the east, through the slope of a
mountain which
similarly inclines to the north. whose hangingwalls
are also in the south, whose footwalls are in the
north, and whose
heads rise toward the north; and lastly, whose rock
seams raise
their heads toward the west. In the third place, they recommend those
veins which extend from XII
north to XII south, through the slope
of a mountain which faces east;
whose hangingwalls are in the
west, whose footwalls are in the east;
whose heads rise toward
the east; and whose rock seams raise their
heads toward the north. Therefore they devote all their energies to those veins, and give very little
or nothing to those whose heads, or the heads of whose rock seams rise
toward the south or west. For although they say these veins some
times show bright specks of
pure metal adhering to the stones, or they come
upon lumps of metal,
yet these are so few and far between that despite them
it is not worth
the trouble to excavate such veins; and miners who persevere
in digging
in the hope of coming upon a quantity of metal, always lose their
time
and trouble. And they say that from veins of this kind, since the sun's
rays draw out
the metallic material, very little metal is gained. But in
this matter the actual experience of the miners who thus judge of
the veins
does not always agree with their opinions, nor is their
reasoning sound;
since indeed the veins which run from east to west
through the slope of a
mountain which inclines to the south, whose
heads rise likewise to the
south, are not less charged with metals,
than those to which miners are
wont to accord the first place in
productiveness; as in recent years has been
proved by the St. Lorentz vein at Abertham, which our countrymen call
Gottsgaab, for they
have dug out of it a large quantity of pure silver; and
lately a vein
in Annaberg, called by the name of Himmelsch hoz
north to the south, with
their heads rising toward the west, are no less rich
in metals than
those whose heads rise toward the east.
It may be denied that the heat of the sun draws the metallic material
out of these veins; for though it draws up vapours from the surface of
the
ground, the rays of the sun do not penetrate right down to the
depths; because
the air of a tunnel which is covered and enveloped by
solid earth to the depth of
only two fathoms is cold in summer, for the
intermediate earth holds in check
the force of the sun. Having observed this fact, the inhabitants and dwellers
of very hot
regions lie down by day in caves which protect them from the
excessive
ardour of the sun. Therefore it is unlikely that the sun draws
out from within the earth
the metallic bodies. Indeed, it cannot even dry
the moisture of many places abounding in
veins, because they are pro
tected and shaded by the trees. Furthermore, certain miners, out of all
the different kinds of metallic
veins, choose those which I have described,
and others, on the
contrary, reject copper mines which are of this sort, so
that there
seems to be no reason in this. For what can be the reason if the
sun draws no copper from copper veins,
that it draws silver from silver veins,
and gold from gold veins?
Moreover, some miners, of whose number was Calbus
between the gold-bearing
rivers and streams. A river, they say, or a stream,
is most productive of fine and coarse
grains of gold when it comes from the
east and flows to the west, and
when it washes against the foot of mountains
which are situated in the
north, and when it has a level plain toward the
south or west. In the second place, they esteem a river or a stream which
flows in the
opposite course from the west toward the east, and which has
the
mountains to the north and the level plain to the south. In the third
place, they esteem the river or the stream which flows from
the north to the
south and washes the base of the mountains which are
situated in the east. But they say that the river or stream is least productive of gold which flows
in a contrary direction from the south to the north, and washes the
base of Lastly, of the streams or rivers
which flow from the rising sun toward
the setting sun, or which flow from
the northern parts to the southern
parts, they favour those which approach
the nearest to the lauded ones,
and say they are more productive of gold,
and the further they depart
from them the less productive they are. Such
are the opinions held about rivers and streams. Now, since gold is not
generated in the rivers and streams, as we have
maintained against
Albertus
V, but is torn
away from the veins and stringers and settled in the sands of
torrents
and water-courses, in whatever direction the rivers or streams flow,
therefore it is reasonable to expect to find gold therein; which is not
opposed by experience. Nevertheless, we do not deny that gold is generated
in veins and
stringers which lie under the beds of rivers or streams, as in
other
places.
END OF BOOK III.
The third book has explained the various and
manifold varieties of veins
and stringers. This
fourth book will deal with mining areas and the
method of
delimiting them, and will then pass on to
the officials who are
connected with mining affairs
Now the miner, if the vein he has uncovered
is to his liking, first of
all goes to the
to request to be granted a right to mine, this
official's
special function and office being to adjudi
cate in respect of the
mines. And so to the first man who has discovered
the vein the
meers, in the order in which each
makes his application. The size of
a meer is measured by fathoms, which for miners are reckoned
at six feet
each. The length, in fact, is that of a man's extended arms and hands
measured
across his chest; but different peoples assign to it different lengths,
Romans
five feet. So this measure which is used by miners seems to
have come down to the
Germans in accordance with the Greek mode of
reckoning. A miner's foot approaches very nearly to the length of a Greek
foot, for
it exceeds it by only three-quarters of a Greek digit, but like that
of
the Romans it is divided into twelve
Now square fathoms are reckoned in units of one, two, three, or more
“measures”, and a “measure” is seven fathoms
each way. Mining
meers are for the most part either square or elongated; in square
meers all the
sides are of equal length, therefore the numbers of
fathoms on the two sides
multiplied together produce the total in
square fathoms. Thus, if the
shape of a “measure” is seven fathoms on every
side, this number multi
plied by itself makes forty-nine square
fathoms.
The sides of a long meer are of equal length, and similarly its ends are
equal; therefore, if the number of fathoms in one of the long sides be
multi
plied by the number of fathoms in one of the ends, the total
produced by the
SHAPE OF A SQUARE MEER.
multiplication is the total number of square
fathoms in the long meer. For
example, the double measure is fourteen fathoms long and seven
broad,
which two numbers multiplied together make ninety-eight square
fathoms.
SHAPE OF A LONG MEER OR DOUBLE MEASURE.
Since meers vary in shape according to the different varieties of veins
it is necessary for me to go more into detail concerning them and
their measurements. If the vein is a
composed of three double measures, therefore it is
forty-two fathoms in
length and seven in width, which numbers
multiplied together give two
hundred and ninety-four square fathoms,
and by these limits the
bounds the owner's rights in a head-meer.
SHAPE OF A HEAD MEER.
The area of every other meer consists of two double measures, on
which
ever side of the head meer it lies, or whatever its number in
order may be,
that is to say, whether next to the head meer, or second,
third, or any later
number. Therefore, it is twenty-eight fathoms long and seven wide, so
multiplying the length by the width we get one hundred and ninety-six
square fathoms, which is the extent of the meer, and by these
boundaries
the
SHAPE OF A MEER.
Now we call that part of the vein which is first discovered and mined,
the head-meer, because all the other meers run from it, just as the
nerves
from the head. The
reason why he apportions a larger
area to the head-meer than to the others, is
that he may give a
suitable reward to the one who first found the vein
and may encourage
others to search for veins. Since meers often reach
to a torrent, or river, or stream, if the last
meer cannot be completed
it is called a fractionIf it is the size of a double measure, the
grants the right of mining
it to him who makes the first application, but if
it is the size of a
single measure or a little over, he divides it between the
nearest
meers on either side of it. It is the custom among miners that
the first meer beyond a stream on
that part of the vein on the opposite
side is a new head-meer, and they
call it the “opposite,”
other meers beyond are only ordinary meers. Formerly every head-meer
was composed of three double measures and one
single one, that is, it was
forty-nine fathoms long and seven wide, and
so if we multiply these two
together we have three hundred and
forty-three square fathoms, which
total gives us the area of an ancient
head-meer.
SHAPE OF AN ANCIENT HEAD-MEER.
Every ancient meer was formed of a single measure, that is to say, it
was seven fathoms in length and width, and was therefore square. In
memory of which miners even now call the width of every meer which is
located on a The following was formerly the
gave
information to the
proceeded personally from the
town to the mountains, or sent thither men
of good repute, at least two
in number, to inspect the metal-bearing vein. Thereupon, if they thought it of sufficient importance to survey, the
again having
gone forth on an appointed day, thus questioned him who first
found the
vein, concerning the vein and the diggings: “Which is your
vein?” “Which digging carried metal?” Then the
discoverer, pointing
his finger to his vein and diggings, indicated
them, and next the
ordered him to approach the windlass and place two fingers of his
right hand
upon his head, and swear this oath in a clear voice:
“I swear by God and
all the Saints, and I call them all to
witness, that this is my vein; and more
over if it is not mine, may
neither this my head nor these my hands henceforth
perform their
functions.” Then the
centre of the windlass,
proceeded to measure the vein with a cord, and to
give the measured
portion to the discoverer,—in the first instance a half and
then
three full measures; afterward one to the King or Prince, another to
his Consort, a third to the Master of the Horse, a fourth to the
Cup-bearer,
a fifth to the Groom of the Chamber, a sixth to himself. Then, starting
from the other side of the windlass, he proceeded to
measure the vein in a
similar manner. Thus the discoverer of the vein obtained the head-meer,
that is, seven
single measures; but the King or Ruler, his Consort, the leading
dignitaries, and lastly, the
ancient meers. This is the reason there are to be found at Freiberg in Meissen
so many
shafts with so many intercommunications on a single vein—which are
to a great extent destroyed by age. If, however, the
fixed the boundaries of the meers on
one side of the shaft for the benefit of
some other discoverer, then
for those dignitaries I have just mentioned,
as many meers as he was
unable to award on that side he duplicated
on the other. But if on both sides of the shaft he had already defined the
boundaries
of meers, he proceeded to measure out only that part of the
vein which
remained free, and thus it sometimes happened that some of
those
persons I have mentioned obtained no meer at all. To-day, though
that old-established custom is observed, the method of
allotting the vein
and granting title has been changed. As I have explained above, the head
meer consists of three double
measures, and each other meer of two
measures, and the
makes the first application. The King or Prince, since all metal is taxed, is
himself content with
that, which is usually one-tenth.
Of the width of every meer, whether old or new, one-half lies on the
footwall side of a If
the vein descends vertically into the earth, the boundaries similarly
descend The owner always holds the mining right for the width of the meer, however
far the vein descends into the depth of the earth.
on application being
made to him, grants to one owner or company a right
the
next meer or two adjoining meers. So much for the shape of meers
and their dimensions in the case of a
I now come to the case of
The boundaries of the areas
For in some places the
profundae,
measures, and the
area of every other mine of two measures, as I have In this case, however, he measures the meers
with a cord, not only
forward and backward from the ends of the head
meer, as he is wont
to do in the case where the owner of a
a meer granted him, but also
from the sides. In this way meers are marked
dílatata
or hill or on a plain. Elsewhere the
head-meer and it is made
fourteen fathoms wide, while the width of each of
the other meers
remains single, that is seven fathoms, but the length is not
defined by
boundaries. In some places the head-meer consists of three
double measures, but has
a width of fourteen fathoms and a length of
twenty-one.
SHAPE OF A HEAD-MEER.
In the same way, every other meer is composed of two measures,
doubled
in the same fashion, so that it is fourteen fathoms in width and
of the
same length.
SHAPE OF EVERY OTHER MEER.
Elsewhere every meer, whether a head-meer or other meer, comprises
forty-two fathoms in width and as many in length.
In other places the
locality
defined by rivers or little valleys as boundaries. But the boundaries
of every such area of whatsoever shape it be, descend
vertically into the
earth; so the owner of that area has a right over
that part of any
dilatata
a
as lies
within the boundaries of his meer; for just as wherever one
profunda
dílatata
Finally, the
for in some localities the head-meer is
composed of three measures, doubled
in such a way that it is fourteen
fathoms wide and twenty-one long; and
every other meer consists of two
measures doubled, and is square, that is,
fourteen fathoms wide and as
many long. In some places the head-meer
is composed of three single measures, and
its width is seven fathoms and
its length twenty-one, which two numbers
multiplied together make one
hundred and forty-seven square
fathoms.
SHAPE OF A HEAD-MEER.
Each other meer consists of one double measure.
In some places the
head-meer is given the shape of a double measure, and
every other meer that
of a single measure. Lastly, in other places the owner or a company is given
a right over
some complete specified locality bounded by little streams,
valleys, or
other limits. Furthermore, all meers on
the case of
each meer has the boundaries so determined
as to prevent disputes arising
between the owners of neighbouring
mines.
The boundary marks in use among miners formerly consisted only of
stones, and from this their name was derived, for now the marks of a
boundary are called “boundary stones.” To-day a row of
posts, made either
of oak or pine, and strengthened at the top with
iron rings to prevent them
from being damaged, is fixed beside the
boundary stones to make them
more conspicuous. By this method in former times the boundaries of the
fields were marked
by stones or posts, not only as written of in the book “
Limítíbus Agrorum,Such
kinds of veins.
Now tunnels are of two sorts, one kind having no right of property, the
other kind having some limited right. For when a miner in some particular
locality is unable to open a vein on
account of a great quantity of water, he
runs a wide ditch, open at the
top and three feet deep, starting on the slope
and running up to the
place where the vein is found. Through it the water
flows off, so that the place is made dry and fit
for digging. But if it is not
sufficiently dried by this open ditch, or if a shaft
which he has now for
the first time begun to sink is suffering from
overmuch water, he goes to
the Having obtained leave, he drives the tunnel, and into its drains all the
water is diverted, so that the place or shaft is made fit for digging. If
it is not seven fathoms from the surface of the earth to the bottom
of this
kind of tunnel, the owner possesses no rights except this one:
namely, that
the owners of the mines, from whose leases the owner of
the tunnel extracts
gold or silver, themselves pay him the sum he
expends within their meer in
driving the tunnel through it.
To a depth or height of three and a half fathoms above and below the
mouth of the tunnel, no one is allowed to begin another tunnel. The reason
for this is that this kind of a tunnel is liable to be
changed into the other
kind which has a complete right of property,
when it drains the meers to a
depth of seven fathoms, or to ten,
according as the old custom in each place
acquires the force of law. In such case this second kind of tunnel has the
following right; in the
first place, whatever metal the owner, or company
owning it, finds in
any meer through which it is driven, all belongs to the
tunnel owner
within a height or depth of one and a quarter fathoms. In
the years which are not long passed, the owner of a tunnel possessed
all the
metal which a miner standing at the bottom of the tunnel
touched with
a bar, whose handle did not exceed the customary length;
but nowadays
a certain prescribed height and width is allowed to the
owner of the tunnel,
lest the owners of the mines be damaged, if the
length of the bar be
longer than usual. Further, every metal-yielding mine which is drained
and supplied with
ventilation by a tunnel, is taxed in the proportion of one
ninth
for the benefit of the owner of the tunnel. But if several tunnels of
this kind are driven through one mining area
which is yielding metals, and
all drain it and supply it with
ventilation, then of the metal which is dug
out from above the bottom
of each tunnel, one-ninth is given to the owner of
that tunnel; of that
which is dug out below the bottom of each tunnel,
one-ninth is in each
case given to the owner of the tunnel which follows
next in order
below. But if the lower tunnel does not yet drain the shaft of
that meer nor
supply it with ventilation, then of the metal which is dug out
below
the bottom of the higher tunnel, one-ninth part is given to the owner
of such upper tunnel. Moreover, no one tunnel deprives another of its
right to one-ninth part,
unless it be a lower one, from the bottom of which
to the bottom of the
one above must not be less than seven or ten fathoms, Further, of all the money
which the owner of the tunnel has spent on his
tunnel while driving it
through a meer, the owner of that meer pays
one-fourth part. If he does
not do so he is not allowed to make use of the drains.
Finally, with regard to whatever veins are discovered by the owner
at
whose expense the tunnel is driven, the right of which has not been
already awarded to anyone, on the application of such owner the
grants him a
right of a head-meer, or of a head-meer together with the next
meer. Ancient custom gives the right for a tunnel to be driven in any
direction for an unlimited length. Further, to-day he who commences a
tunnel is given, on his application,
not only the right over the tunnel, but
even the head and sometimes the
next meer also. In former days the owner
of the tunnel obtained only so much ground as
an arrow shot from the bow
might cover, and he was allowed to pasture
cattle therein. In a case where
the shafts of several meers on some vein could not be
worked on account of
the great quantity of water, ancient custom also
allowed the
grant the right of a large meer to anyone who would drive a tunnel. When,
however, he had driven a tunnel as far as the old shafts and had
found
metal, he used to return to the
mark off the extent of his right to a meer. Thereupon, the
together with a certain number of citizens of the town—in whose
place
Jurors have now succeeded—used to proceed to the mountain
and mark off
with boundary stones a large meer, which consisted of
seven double
measures, that is to say, it was ninety-eight fathoms long
and seven wide,
which two numbers multiplied together make six hundred
and eighty-six
square fathoms.
LARGE AREA.
But each of these early customs has been changed, and we now employ
the
new method.
I have spoken of tunnels; I will now speak about the division of
owner
ship in mines and tunnels. One owner is allowed to possess and to work
one, two, three, or more
whole meers, or similarly one or more separate
tunnels, provided he
conforms to the decrees of the laws relating to
metals, and to the
orders of the And because he alone pro
vides the expenditure of money on the
mines, if they yield metal he alone
obtains the product from them. But when large and frequent expenditures
are necessary in mining, he to
whom the
company, and they each lay out
a part of the expense and share with him
the profit or loss of the
mine. But the title of the mines or tunnels remains
undivided, although for
the purpose of dividing the expense and profit it
may be said each mine
or tunnel is divided into parts
This division is made in various ways.
A mine, and the same thing
must be understood with regard to a tunnel,
may be divided into two halves,
that is into two similar portions, by
which method two owners spend
an equal amount on it and draw an equal
profit from it, for each possesses
one half. Sometimes it is divided into four shares, by which compact
four persons
can be owners, so that each possesses one-fourth, or also two
persons,
so that one possesses three-fourths, and the other only
one-fourth
or three owners, so that the first has two-fourths, and
the second and third
one-fourth each. Sometimes it is divided into eight shares, by which plan
there may be
eight owners, so that each is possessor of one-eighth; some
times
there are two owners, so that one has five-sixths
twenty-fourth, and the
other one-eighth; or there may be three owners, in
which one has
three-quarters and the second and third each one-eighth;
or it may be
divided so that one owner has seven-twelfths, together with
one
twenty-fourth, a second owner has one-quarter, and a third owner has
one-eighth; or so that the first has one-half, the second one-third and
one
twenty-fourth, and the third one-eighth; or so that the first has
one-half,
as before, and the second and third each one-quarter; or so
that the first
and second each have one-third and one twenty-fourth,
and the third one
quarter; and in the same way the divisions may be
adjusted in all the other
proportions. The different ways of dividing the shares originate from the
different
proportions of ownership. Sometimes a mine is divided into
sixteen parts, each of which is a
twenty-fourth and a forty-eighth; or it may
be divided into thirty-two
parts, each of which is a forty-eighth and half a
seventy-second and a
two hundred and eighty-eighth; or into sixty-four
parts of which each
share is one seventy-second and one five hundred and
seventy-sixth; or
finally, into one hundred and twenty-eight parts, any one
of which is
half a seventy-second and half of one five hundred and
seventy
sixth.
Now an iron mine either remains undivided or is divided into two,
four,
or occasionally more shares, which depends on the excellence of the
veins. But a lead, bismuth, or tin mine, and likewise one of copper or even
quicksilver, is also divided into eight shares, or into sixteen or
thirty-two,
and less commonly into sixty-four. The number of the divisions of the silver
mines at Freiberg in Meissen
did not formerly progress beyond this; but
similarly
the tunnel at Schneeberg, first of all into one hundred and
twenty
eight shares, of which one hundred and twenty-six are the
property of
private owners in the mines or tunnels, one belongs to the
State and one
to the Church; while in Joachimsthal only one hundred and
twenty-two
shares of the mines or tunnels are the property of private
owners, four
are proprietary shares, and the State and Church each have
one in the
same way. To these there has lately been added in some places one share
for the
most needy of the population, which makes one hundred and
twenty
nine shares. It is only the private owners of mines who pay contributions.
A proprietary holder, though he holds as many as four shares such as I have
described, does not pay contributions, but gratuitiously supplies the
owners
of the mines with sufficient wood from his forests for
timbering, machinery,
buildings, and smelting; nor do those belonging
to the State, Church, and
the poor pay contributions, but the proceeds
are used to build or repair
public works and sacred buildings, and to
support the most needy with the
profits which they draw from the mines. Furthermore, in our State, the
one hundred and twenty-eighth share has
begun to be divided into two,
four, or eight parts, or even into three,
six, twelve, or smaller parts. This
is done when one mine is created out of two, for then the owner who
formerly
possessed one-half becomes owner of one-fourth; he who
possessed one
fourth, of one-eighth; he who possessed one-third, of
one-sixth; he who
possessed one-sixth, of one-twelfth. Since our countrymen call a mine a
the owners subscribe a For, just as those who
go to a banquet (
making large profits from mining are accustomed to contribute toward
the
expenditure. However, the manager of the mine assesses the contributions
of the
owners annually, or for the most part quarterly, and as often he
renders an account of receipts and expenses. At Freiberg in Meissen the
old practice was for the manager to exact a
contribution from the owners
every week, and every week to distribute
among them the profits of the
mines, but this practice during almost
the last fifteen years has been so far
changed that contribution and
distribution are made four
year. Large or small contributions are imposed according to the number
of
workmen which the mine or tunnel requires; as a result, those who
possess many shares provide many contributions. Four times a year the
owners contribute to the cost, and four times
during the year the profits of
the mines are distributed among them;
these are sometimes large, some
times small, according as there is
more or less gold or silver or other metal
dug out. Indeed, from the St.
George mine in Schneeberg the miners extracted
so much silver in a
quarter of a year that silver cakes, which were worth
share. From the Annaberg mine which is known as the Himmelich Höz,
they
had a dole of eight hundred thaler; from a mine in Joachimsthal
which
is named the Sternen, three hundred thaler; from the head mine at
Abertham, which is called St. Lorentz, two hundred and twenty-five thaler
The more shares of which any individual is owner the more profits he
takes.
I will now explain how the owners may lose or obtain the right over a
mine, or a tunnel, or a share. Formerly, if anyone was able to prove by
witnesses that the owners had
failed to send miners for three continuous
shifts
gave the right over it to the informer, if he
desired it. But although miners
preserve this custom to-day, still mining share
owners who have paid
their contributions do not lose their right over
their mines against their will. Formerly, if water which had not been drawn off from the higher shaft of
some mine percolated through a vein or stringer into the shaft of
another
mine and impeded their work, then the owners of the mine which
suffered
the damage went to the
to the shafts two Jurors. If they found that matters were as claimed,
the right over the mine
which caused the injury was given to the owners
who suffered the
injury. But this custom in certain places has been changed,
for the
of two shafts, orders
the owners of the shaft which causes the injury to
contribute part of
the expense to the owners of the shaft which receives the
injury; if
they fail to do so, he then deprives them of their right over their
mine; on the other hand, if the owners send men to the workings to dig
and draw off the water from the shafts, they keep their right over
their
mine. Formerly owners used to obtain a right over any tunnel, firstly, if
in
its bottom they made drains and cleansed them of mud and sand so that
the water might flow out without any hindrance, and restored those
drains
which had been damaged; secondly, if they provided shafts or
openings to
supply the miners with air, and restored those which had
fallen in; and
finally, if three miners were employed continuously in
driving the tunnel. But the principal reason for losing the title to a tunnel was that for a
period
of eight days no miner was employed upon it; therefore, when
anyone
was able to prove by witnesses that the owners of a tunnel had
not done
these things, he brought his accusation before the
going out from the town to the tunnel and inspecting the drains and the
ventilating machines and everything else, and finding the charge to be
true,
placed the witness under oath, and asked him: “Whose tunnel
is this at the
present time?” The witness would reply: “The
King's” or “The
the first
applicant. This was the severe rule under which the owners at one
time lost their
rights over a tunnel; but its severity is now considerably
mitigated,
for the owners do not now forthwith lose their right over a tunnel
through not having cleaned out the drains and restored the shafts or
ventilation holes which have suffered damage; but the
the
tunnel manager to do it, and if he does not obey, the authorities fine
the tunnel. Also it is sufficient for one miner to be engaged in driving the
tunnel. Moreover, if the owner of a tunnel sets boundaries at a fixed spot
in
the rocks and stops driving the tunnel, he may obtain a right over it so
far as he has gone, provided the drains are cleaned out and ventilation
holes are kept in repair. But any other owner is allowed to start from the
established mark and
drive the tunnel further, if he pays the former owners
of the tunnel as
much money every three months as the
ought to be
paid.
There remain for discussion, the shares in the mines and tunnels.
Formerly if anybody conveyed these shares to anyone else, and the latter
had once paid his contribution, the seller
and this custom
to-day has the force of law. But if the seller denied that the
contribution had been paid, while the
buyer of the shares declared that he could
prove by witnesses that he
had paid his contribution to the other proprietors,
and a case arose
for trial, then the evidence of the other proprietors carried
more
weight than the oath of the seller. To-day the buyer of the shares proves
that he has paid his contribution
by a document which the mine or tunnel
manager always gives each one;
if the buyer has contributed no money
there is no obligation on the
seller to keep his bargain. Formerly, as I have
said above, the proprietors used to contribute money
weekly, but now con
tributions are paid four times each year. To-day, if for the space of a month
anyone does not take proceedings
against the seller of the shares for the con
tribution, the right
of taking proceedings is lost. But when the Clerk has
already entered on the register the shares which
had been conveyed or
bought, none of the owners loses his right over
the share unless the money
is not contributed which the manager of the
mine or tunnel has demanded
from the owner or his agent. Formerly, if on the application of the manager
the owner or his agent
did not pay, the matter was referred to the
meister,
if he failed to contribute
for three successive weeks, the
the right to his shares to the first
applicant. To-day this custom is un
changed, for if owners fail for the space
of a month to pay the contribu
tions which the manager of the mine
has imposed on them, on a stated day
their names are proclaimed aloud
and struck off the list of owners, in
the presence of the
Clerk, and each of such shares
is entered on the proscribed list. If, how
to the manager of the mine or tunnel,
and pay the money which is due from
them to the Share Clerk, he removes
their shares from the proscribed
list. They are not thereupon restored to their former position unless the
other owners consent; in which respect the custom now in use differs
from
the old practice, for to-day if the owners of shares constituting
anything
over half the mine consent to the restoration of those who
have been
proscribed, the others are obliged to consent whether they
wish to or not. Formerly, unless such restoration had been sanctioned by the approval of
the owners of one hundred shares, those who had been proscribed were
not
restored to their former position.
The procedure in suits relating to shares was formerly as follows: he
who instituted a suit and took legal proceedings against another in
respect
of the shares, used to make a formal charge against the accused
possessor
before the This was done either at his house or in some public
place or at the
mines, once each day for three days if the shares belonged to
an old
mine, and three times in eight days if they belonged to a
head
meer. But if he could not find the possessor of the shares in these places, it
was valid and effectual to make the accusation against him at the house
of
the When, however, he made the charge for the third time, he
used to bring
with him a notary, whom the
“Have I earned the
fee?” and who would respond: “You have earned
it”;
thereupon the
who
made the accusation, and the accuser in turn would pay down the
customary fee to the After these proceedings, if the man whom
the
proprietors of the mine or of the
head-mine was sent to him to acquaint him
with the facts, but if he
dwelt elsewhere proclamation was made in some
public place, or at the
mine, openly and in a loud voice in the hearing of
numbers of miners. Nowadays a date is defined for the one who is answer
able for the
debt of shares or money, and information is given the accused
by an
official if he is near at hand, or if he is absent, a letter is sent him;
nor is the right over his shares taken from anyone for the space of one
and
a half months. So much for these matters.
Now, before I deal with the methods which must be employed in
working, I
will speak of the duties of the Mining Prefect, the
the Jurors, the Mining
Clerk, the Share Clerk, the manager of the mine
or tunnel, the foreman
of the mine or tunnel, and the workmen.
To the Mining Prefect, whom the King or Prince appoints as his deputy,
all men of all races, ages, and rank, give obedience and submission. He
governs and regulates everything at his discretion, ordering those
things
which are useful and advantageous in mining operations, and
prohibiting
those which are to the contrary. He levies penalties and punishes offenders;
he arranges disputes which
the
even he cannot arrange them, he allows
the owners who are at variance over
some point to proceed to
litigation; he even lays down the law, gives orders
mines the pay of persons who hold any post or office. He is present in
person when the mine managers present their quarterly
accounts of profits
and expenses, and generally represents the King or
Prince and upholds his
dignity. The Athenians in this way set Thucydides, the famous historian,
over the
mines of Thasos
Next in power to the Mining Prefect comes the
has
jurisdiction over all who are connected with mines, with a few exceptions,
which are the Tithe Gatherer, the Cashier, the Silver Refiner, the
Master
of the Mint, and the Coiners themselves. Fraudulent, negligent, or dissolute
men he either throws into prison, or
deprives of promotion, or fines;
of these fines, part is given as a
tribute to those in power. When the mine
owners have a dispute over boundaries he arbitrates it; or
if he cannot
settle the dispute, he pronounces judgment jointly with
the Jurors;
from them, however, an appeal lies to the Mining Prefect. He transcribes
his decrees in a book and sets up the records in public. It is also his duty
to grant the right over the mines to those who
apply, and to confirm their
rights; he also must measure the mines, and
fix their boundaries, and see
that the mine workings are not allowed to
become dangerous. Some of
these duties he observes on fixed days; for on Wednesday in the
presence
of the Jurors he confirms the rights over the mines which he
has granted,
settles disputes about boundaries, and pronounces
judgments. On Mondays,
Tuesdays, Thursdays, and Fridays, he rides up to the mines,
and dismounting
at some of them explains what is required to be done,
or considers the
boundaries which are under controversy. On Saturday all the mine managers
and mine foremen render an account of
the money which they have spent
on the mines during the preceding week,
and the Mining Clerk transcribes
this account into the register of
expenses. Formerly, for one Principality
there was one
jurisdiction and control over them; for every mine
had its own judge,
just as to-day each locality has a
being changed. To this ancient
Meissen, disputes were referred; hence
right up to the present time the one
at Freiberg still has the power of
pronouncing judgment when mine owners
who are engaged in disputes among
themselves appeal to him. The old
whatsoever; whereas the judge could only try the things which were done
in his own district, in the same way that every modern
To each
signifying to the applicant
for a right over a mine, the day and hour on which
the right is
granted, the name of the applicant, and the location of the mine. He also affixes at the entrance to the mine, quarterly, at the appointed
time,
a sheet of paper on which is shown how much contribution must be
paid to
the manager of the mine. These notices are prepared jointly with the
of the
separate mines.
I now come to the Jurors, who are men experienced in mining
matters and
of good repute. Their number is greater or less as there
are few or more mines; thus if
there are ten mines there will be five
pairs of Jurors, like a Into however many
divisions the total number of mines has been divided,
so many divisions
has the body of Jurors; each pair of Jurors usually
visits some of
the mines whose administration is under their
supervision on every
day that workmen are employed; it is usually so
arranged that they
visit all the mines in the space of fourteen days. They inspect and con
sider all details, and deliberate and consult
with the mine foreman on
matters relating to the underground workings,
machinery, timbering, and
everything else. They also jointly with the mine foreman from time to
time make the price
per fathom to the workmen for mining the ore, fixing
it at a high or
low price, according to whether the rock is hard or soft; if,
however,
the contractors find that an unforeseen and unexpected hardness
occurs,
and for that reason have difficulty and delay in carrying out their
work, the Jurors allow them something in excess of the price fixed;
while if there is a softness by reason of water, and the work is done
more
easily and quickly, they deduct something from the price. Further, if the
Jurors discover manifest negligence or fraud on the part
of any foreman
or workman, they first admonish or reprimand him as to
his duties and
obligations, and if he does not become more diligent and
improve, the matter
is reported to the
persons of their functions and office, or, if they have
committed a crime,
throws them into prison. Lastly, because the Jurors have been given
to the
confirm the right over any mine, nor measure
the mines, nor fix their
boundaries, nor settle disputes about
boundaries, nor pronounce judgment,
nor, finally, does he without them
listen to any account of profits and
expenditure.
Now the Mining Clerk enters each mine in his books, the new mines
in one
book, the old mines which have been re-opened in another. This
is done in the following way: first is written the name of the man
who has
applied for the right over the mine, then the day and hour on
which he
made his application, then the vein and the locality in which
it is situated,
next the conditions on which the right has been given,
and lastly, the day on
which the A document containing all these
particulars is also given to the person
whose right over a mine has been
confirmed. The Mining Clerk also sets down in another book the names
of the owners
of each mine over which the right has been confirmed;
in another any
intermission of work permitted to any person for cer
supplies to
another for drawing off water or making machinery; and in
another the
decisions of the
settled by them as honorary
arbitrators. All these matters he enters in the
books on Wednesday of every week; if
holidays fall on that day he does it
on the following Thursday. Every Saturday he enters in another book the
total expenses of the
preceding week, the account of which the mine manager
has rendered; but
the total quarterly expenses of each mine manager, he
enters in a
special book at his own convenience. He enters similarly in
another book a list of owners who have been
proscribed. Lastly, that no one
may be able to bring a charge of falsification
against him, all these books
are enclosed in a chest with two locks,
the key of one of which is kept by the
Mining Clerk, and of the other
by the
The Share Clerk enters in a book the owners of each mine whom
the first
finder of the vein names to him, and from time to time replaces the
names of the sellers with those of the buyers of the shares. It sometimes
happens that twenty or more owners come into the possession
of some
particular share. Unless, however, the seller is present, or has sent a letter
to the
Mining Clerk with his seal, or better still with the seal of the Mayor
of the town where he dwells, his name is not replaced by that of anyone
else;
for if the Share Clerk is not sufficiently cautious, the law
requires him
to restore the late owner wholly to his former position. He writes out a
fresh document, and in this way gives proof of
possession. Four times a
year, when the accounts of the quarterly expenditure are
rendered, he
names the new proprietors to the manager of each mine,
that the manager
may know from whom he should demand contributions and
among whom
to distribute the profits of the mines. For this work the mine manager pays
the Clerk a fixed fee.
I will now speak of the duties of the mine manager.
In the case of the
owners of every mine which is not yielding metal, the
manager announces
to the proprietors their contributions in a document
which is affixed to the
doors of the town hall, such contributions
being large or small, according as
the If anyone fails to pay these
contributions for the space of a month, the
manager removes their names
from the list of owners, and makes their
shares the common property of the
other proprietors. And so, whomsoever the mine manager names as not
having paid his
contribution, that same man the Mining Clerk designates
in writing, and
so also does the Share Clerk. Of the contribution, the
mine manager applies part to the payment of the
foreman and workmen,
and lays by a part to purchase at the lowest price
the necessary things for
the mine, such as iron tools, nails, firewood,
planks, buckets, drawing-ropes,
or grease. But in the case of a mine which is yielding metal, the
Tithe
gatherer pays the mine manager week by week as much money as
suffices
to discharge the workmen's wages and to provide the necessary
implements
for mining. The mine manager of each mine also, in the presence of its
foreman, on
Saturday in each week renders an account of his expenses to
whether the money has
been contributed by the owners or taken from the
Tithe-gatherer; and of
his quarterly expenditure in the same way
to them and to the Mining
Prefect and to the Mining Clerk, four
times a year at the appointed
time; for just as there are four seasons
of the year, namely, Spring,
Summer, Autumn, and Winter, so there are
fourfold accounts of profits
and expenses. In the beginning of the first
month of each quarter an account is
rendered of the money which the
manager has spent on the mine during
the previous quarter, then of the
profit which he has taken from it
during the same period; for example,
the account which is rendered at
the beginning of spring is an account of all
the profits and expenses
of each separate week of winter, which have been
entered by the Mining
Clerk in the book of accounts. If the manager
has spent the money of the proprietors advantageously in
the mine and
has faithfully looked after it, everyone praises him as a
diligent and honest
man; if through ignorance in these matters he has
caused loss, he is generally
deprived of his office; if by his
carelessness and negligence the owners have
suffered loss, the
if he has been guilty of fraud or
theft, he is punished with fine, prison, or
death. Further, it is the business of the manager to see that the foreman
of
the mine is present at the beginning and end of the shifts, that he digs
the ore in an advantageous manner, and makes the required timbering,
machines, and drains. The manager also makes the deductions from the
pay of the workmen whom
the foreman has noted as negligent. Next,
if the mine is rich in metal, the manager must see that its
ore-house is closed
on those days on which no work is performed; and if
it is a rich vein of gold
or silver, he sees that the miners promptly
transfer the output from the shaft
or tunnel into a chest or into the
strong room next to the house where the
foreman dwells, that no
opportunity for theft may be given to dishonest
persons. This duty he shares in common with the foreman, but the one
which
follows is peculiarly his own. When ore is smelted he is present in
person, and watches that the
smelting is performed carefully and advan
tageously. If from it gold or silver is melted out, when it is melted in the
cupellation furnace he enters the weight of it in his books and carries
it
to the Tithe-gatherer, who similarly writes a note of its weight in
his books;
it is then conveyed to the refiner. When it has been brought back, both
the Tithe-gatherer and manager again
enter its weight in their books. Why
again? Because he looks after the goods of the owners just as if they were
his
own. Now the laws which relate to mining permit a manager to have
charge of
more than one mine, but in the case of mines yielding gold or
silver,
to have charge of only two. If, however, several mines following the
head-mine begin to produce
metal, he remains in charge of these others until
he is freed from the
duty of looking after them by the Last of
all, the manager, the
with the owners, settle the remuneration for the labourers. Enough of the
duties and occupation of the manager.
I will now leave the manager, and discuss him who controls the workmen
of the mine, who is therefore called the foreman, although some call
him
the watchman. It is he who distributes the work among the labourers, and
sees
diligently that each faithfully and usefully performs his duties. He
also discharges workmen on account of incompetence, or negligence,
and
supplies others in their places if the two Jurors and manager give
their
consent. He must be skilful in working wood, that he may timber shafts,
place
posts, and make underground structures capable of supporting an
under
mined mountain, lest the rocks from the hangingwall of the
veins, not being
supported, become detached from the mass of the
mountain and over
whelm the workmen with destruction. He must be able to make and lay
out the drains in the tunnels, into
which the water from the veins, stringers,
and seams in the rocks may
collect, that it may be properly guided and
can flow away. Further, he must be able to recognize veins and stringers,
so as to sink
shafts to the best advantage, and must be able to discern one
kind of
material which is mined from another, or to train his subordinates
that
they may separate the materials correctly. He must also be well
acquainted with all methods of washing, so as to
teach the washers how
the metalliferous earth or sand is washed. He supplies the miners with iron
tools when they are about to start to
work in the mines, and apportions a
certain weight of oil for their
lamps, and trains them to dig to the best
advantage, and sees that they
work faithfully. When their shift is finished,
he takes back the oil which has been left. On account of his numerous and
important duties and labours, only one
mine is entrusted to one foreman,
nay, rather sometimes two or three
foremen are set over one mine.
Since I have mentioned the shifts, I will briefly explain how these are
carried on. The twenty-four hours of a day and night are divided into three
shifts,
and each shift consists of seven hours. The three remaining hours are
intermediate between the shifts, and form
an interval during which the
workmen enter and leave the mines. The first shift begins at the fourth hour
in the morning and lasts till
the eleventh hour; the second begins at the
twelfth and is finished at
the seventh; these two are day shifts in the
morning and afternoon. The third is the night shift, and commences at the
eighth hour in the
evening and finishes at the third in the morning. The
unless necessity
demands it. In that case, whether they draw water from
the shafts or mine the ore,
they keep their vigil by the night lamps, and to
prevent themselves
falling asleep from the late hours or from fatigue, they
lighten their
long and arduous labours by singing, which is neither wholly
untrained
nor unpleasing. In some places one miner is not allowed to
undertake two shifts in
succession, because it often happens that he either
falls asleep in the
mine, overcome by exhaustion from too much labour, or
arrives too late
for his shift, or leaves sooner than he ought. Elsewhere he
is allowed to do so, because he cannot subsist on the pay
of one shift,
especially if provisions grow dearer. The
forbid an extraordinary shift when he concedes only one
ordinary shift.
call a “campana,”
gives the workmen warning, and when this is heard they
run hither and
thither through the streets toward the mines. Similarly,
the same sound of the bell warns the foreman that a shift has
just been
finished; therefore as soon as he hears it, he stamps on the
woodwork of the
shaft and signals the workmen to come out. Thereupon, the nearest as soon
as they hear the signal, strike the rocks
with their hammers, and the sound
reaches those who are furthest away. Moreover, the lamps show that the
shift has come to an end when the oil
becomes almost consumed and fails
them. The labourers do not work on Saturdays, but buy those things which
are
necessary to life, nor do they usually work on Sundays or annual
festivals, but on these occasions devote the shift to holy things. However,
the workmen do not rest and do nothing if necessity demands
their labour;
for sometimes a rush of water compels them to work,
sometimes an impending
fall, sometimes something else, and at such
times it is not considered
irreligious to work on holidays. Moreover, all workmen of this class are
strong and used to toil from
birth.
The chief kinds of workmen are miners, shovelers, windlass men, carriers,
sorters, washers, and smelters, as to whose duties I will speak in the
fol
lowing books, in their proper place. At present it is enough to add this one
fact, that if the workmen have
been reported by the foreman for negligence,
the
dismisses them from their work on
Saturday, or deprives them of part of
their pay; or if for fraud,
throws them into prison. However, the owners
of works in which the metals are smelted, and the
master of the smelter, look
after their own men. As to the government and duties of miners, I have
now said enough; I
will explain them more fully in another work entitled
END OF BOOK IV.
In the last book I have explained the methods of
delimiting the meers
along each kind of vein, and
the duties of mine officials. In this book
in like
manner explain the principles of under
ground mining and the art of
surveying. First
then, I will proceed to deal with those matters
which pertain
to the former heading, since both the
subject and methodical
arrangement require it. And so I will describe first of all the digging of
shafts, tunnels, and
drifts on
indications shown by
the rocks;
then I will speak of the tools by which veins and rocks are broken
down
and excavated; the method by which fire shatters the hard veins;
and
further, of the machines with which water is drawn from the shafts
and
air is forced into deep shafts and long tunnels, for digging is impeded
by the inrush of the former or the failure of the latter; next I will
deal
with the two kinds of shafts, and with the making of them and of
tunnels;
and finally, I will describe the method of mining
latae,
Now when a miner discovers a
and above it sets up a
windlass, and builds a shed over the shaft to prevent
the rain from
falling in, lest the men who turn the windlass be numbed
by the cold or
troubled by the rain. The windlass men also place their
barrows in it, and the miners store
their iron tools and other implements therein. Next to the shaft-house another house is built, where the mine foreman and
the
other workmen dwell, and in which are stored the ore and other
things which
are dug out. Although some persons build only one house, yet because
sometimes boys
and other living things fall into the shafts, most miners
deliberately
place one house apart from the other, or at least separate them
by a
wall.
Now a shaft is dug, usually two fathoms long, two-thirds of a fathom
wide, and thirteen fathoms deep; but for the purpose of connecting with
a
tunnel which has already been driven in a hill, a shaft may be sunk
to a
depth of only eight fathoms, at other times to fourteen, more or
lessA
shaft may be made vertical or inclined, according as the vein which
the
miners follow in the course of digging is vertical or inclined. A tunnel is a
subterranean ditch driven lengthwise, and is nearly twice
as high as it is
broad, and wide enough that workmen and others may be
able to pass and
carry their loads. It is usually one and a quarter fathoms high, while
its width is about
three and three-quarters feet. Usually two workmen are
required to drive it, one of whom digs out the
upper and the other the lower
part, and the one goes forward, while the
other follows closely after. Each
sits upon small boards fixed securely from the footwall to the
hangingwall,
or if the vein is a soft one, sometimes on a wedge-shaped
plank fixed on to the
vein itself. Miners sink more inclined shafts than vertical, and some of each
kind do
not reach to tunnels, while some connect with them. But as for
some shafts, though they have already been sunk to the
required depth,
the tunnel which is to pierce the mountain may not yet
have been driven
far enough to connect with them.
It is advantageous if a shaft connects with a tunnel, for then the miners
and other workmen carry on more easily the work they have undertaken;
but if the shaft is not so deep, it is usual to drift from one or both
sides of it. From these openings the owner or foreman becomes acquainted with the
veins and stringers that unite with the principal vein, or cut across
it, or
THREE VERTICAL SHAFTS, OF WHICH THE FIRST, A, DOES NOT REACH THE TUNNEL; THE
SECOND, B, REACHES THE TUNNEL; TO THE THIRD, C, THE TUNNEL HAS NOT YET
BEEN
DRIVEN. D—TUNNEL.
along after the manner of a tunnel, they are entirely hidden
within the
THREE INCLINED SHAFTS, OF WHICH A DOES NOT YET REACH THE TUNNEL; B REACHES
THE
TUNNEL; TO THE THIRD, C, THE TUNNEL HAS NOT YET BEEN DRIVEN.
D—TUNNEL.This kind of an opening, however, differs from a tunnel in that it
is
dark throughout its length. whereas a tunnel has a mouth open to daylight.
A—SHAFT. B, C—DRIFT. D—ANOTHER SHAFT. E—TUNNEL.
F—MOUTH OF TUNNEL.
I have spoken of shafts, tunnels, and drifts.
I will now speak of the
indications given by the
the rocks. These indications, as also many others which I will explain, are
to a
great extent identical in
profundae.
When a stringer junctions with a main vein and causes a swelling, a
shaft should be sunk at the junction. But when we find the stringer inter
secting the main vein crosswise
or obliquely, if it descends vertically down
to the depths of the
earth, a second shaft should be sunk to the point where
the stringer
cuts the main vein; but if the stringer cuts it obliquely the
shaft
should be two or three fathoms back, in order that the junction may
be
pierced lower down. At such junctions lies the best hope of finding the
ore for the sake of
which we explore the ground, and if ore has already been
found, it is
usually found in much greater abundance at that spot. Again,
if several stringers descend into the earth, the miner, in order
to pierce
through the point of contact, should sink the shaft in the
midst of these
stringers, or else calculate on the most prominent
one.
Since an inclined vein often lies near a vertical vein, it is advisable
to sink a shaft at the spot where a stringer or cross-vein cuts them
both;
or where a
are usually found
there. In the same way we have a good prospect of finding
metal at the point
where an inclined vein joins a vertical one; this is why
miners
cross-cut the hangingwall or footwall of a main vein, and in these
openings seek for a vein which may junction with the principal vein a
few
fathoms below. Nay, further, these same miners, if no stringer or cross
vein
intersects the main vein so that they can follow it in their workings,
even cross-cut through the solid rock of the hangingwall or footwall. These
cross-cuts are likewise called “
opening
which has to be undertaken is made from a tunnel or from a drift. Miners have some hope when only a cross vein cuts a main vein.
Further,
if a vein which cuts the main vein obliquely does not appear
anywhere
beyond it, it is advisable to dig into that side of the main
vein toward which
the oblique vein inclines, whether the right or left
side, that we may ascer
tain if the main vein has absorbed it; if
after cross-cutting six fathoms it
is not found, it is advisable to dig
on the other side of the main vein, that
we may know for certain
whether it has carried it forward. The owners
of a main vein can often dig no less profitably on that side
where the vein
which cuts the main vein again appears, than where it
first cuts it; the
owners of the intersecting vein, when that is found
again, recover their title,
which had in a measure been lost.
The common miners look favourably upon the stringers which come
from the
north and join the main vein; on the other hand, they look
unfavourably
upon those which come from the south, and say that these do
much harm
to the main vein, while the former improve it. But I think
that miners should not neglect either of them: as I showed
in Book III,
experience does not confirm those who hold this opinion
about veins, so now
common miners which have proved
good, but I know this could be of little
or no benefit to
posterity.
If the miners find no stringers or veins in the hangingwall or footwall of
the main vein, and if they do not find much ore, it is not worth while
to
undertake the labour of sinking another shaft. Nor ought a shaft to be sunk
where a vein is divided into two or three
parts, unless the indications are
satisfactory that those parts may be
united and joined together a little later. Further, it is a bad indication for a vein rich in mineral to bend and turn
hither and thither, for unless it goes down again into the ground
vertically or
inclined, as it first began, it produces no more metal;
and even though it
does go down again, it often continues barren. Stringers which in their
outcrops bear metals, often disappoint miners,
no metal being found in depth. Further, inverted seams in the rocks are counted among the bad
indications.
The miners hew out the whole of solid veins when they show clear evidence
of being of good quality; similarly they hew out the drusy
especially if the
cavities are plainly seen to have formerly borne metal, or
if the
cavities are few and small. They do not dig barren veins through
which water flows, if there are no
metallic particles showing; occasionally,
however, they dig even barren
veins which are free from water, because
of the pyrites which is devoid
of all metal, or because of a fine black soft
substance which is like
wool. They dig stringers which are rich in metal,
or sometimes, for the
purpose of searching for the vein, those that are devoid
of ore which
lie near the hangingwall or footwall of the main vein. This
then, generally speaking, is the mode of dealing with stringers and
veins.
Let us now consider the metallic material which is found in the
of
either cohesive and continuous,
or scattered and dispersed among them,
or swelling out in bellying
shapes, or found in veins or stringers which
originate from the main
vein and ramify like branches; but these latter veins
and stringers are
very short, for after a little space they do not appear again. If we come across a small quantity of metallic material it is an indication;
but if a large quantity, it is not an “indication,” but the
very thing for
which we explore the earth. As soon as a miner who searches for veins
discovers pure metal or
minerals, or rich metallic material, or a great
abundance of material
which is poor in metal, let him sink a shaft on the
spot without any
delay. If the material appears more abundant or of better
quality on the one
side, he will incline his digging in that direction.
Gold, silver, copper, and quicksilver are often found native
often iron and bismuth; almost
never tin and lead. Nevertheless tin-stone
is not far removed from the pure white tin which
is melted out of them, and
galena, from which lead is obtained, differs
little from that metal itself.
Now we may classify gold ores.
Next after native gold, we come to the
gold colour. These must be reckoned as the richest ores, because the gold
exceeds the
stone or earth in weight. Next come all gold ores of which each.
one hundred
a
small proportion of gold is found in the earth or stone, yet it equals in
value
other metals of greater weight.A vein which contains a
larger proportion of silver than of gold is
rarely found to be a rich one. Earth, whether it be dry or wet, rarely abounds in gold; but in dry earth
there is more often found a greater quantity of gold, especially if it
has the
scales resembling mica. The solidified juices, azure, chrysocolla, orpiment,
and realgar, also
frequently contain gold. Likewise native or
found sometimes in large, and sometimes in small quantities
in quartz,
degree, and which is sometimes so porous
that it seems completely decom
posed. Lastly, gold is found in pyrites, though rarely in large quantities.
When considering silver ores other than native silver, those ores are
This quality comprises
ruby silver, or whether white, or
black, or grey, or purple, or yellow, or liver-Sometimes quartz, schist, or marble is of this quality
also, if much
native or But that ore is considered
of poor quality if three
one hundred
is mixed
with all kinds of earth and stone compounds, except the various
kinds
of
As regards other kinds of metal, although some rich ores are found,
still, unless the veins contain a large quantity of ore, it is very
rarely worth
while to dig them. The Indians and some other races do search for gems in
veins hidden deep
in the earth, but more often they are noticed from their
clearness, or
rather their brilliancy, when metals are mined. When they
outcrop, we follow veins of marble by mining in the same way
as is
done with rock or building-stones when we come upon them. But
gems, properly so called, though they sometimes have veins of their
own,
are still for the most part found in mines and rock quarries, as
the
lodestone in iron mines, the emery in silver mines, the
trochítes,
of the owners, usually
collect them from the seams in the rocks.
miner neglect the digging of
“extraordinary earths,”
if they are
found in stone quarries, or in their own veins; their value is usually
indicated by their taste. Nor, lastly, does the miner fail to give attention to
the solidified
juices which are found in metallic veins, as well as in their own
veins, from which he collects and gathers them. But I will say no more
on these matters, because I have explained more
fully all the metals and
mineral substances in the books “
But I will return to the indications.
If we come upon earth which is
like lute, in which there are particles
of any sort of metal, native or
the best possible indication of a vein is given to
miners, for the metallic
material from which the particles have become
detached is necessarily close
by. But if this kind of earth is found absolutely devoid of all metallic
material, but fatty, and of white, green, blue, and similar colours,
they must
not abandon the work that has been started. Miners have other indications in
the veins and stringers, which I have
described already, and in the rocks, about
which I will speak a little
later. If the miner comes across other dry earths
which contain native or
across yellow, red, black, or some other
“extraordinary” earth, though it is
devoid of mineral, it
is not a bad indication. Chrysocolla, or azure, or verdigris,
or orpiment, or realgar, when they
are found, are counted among the good
indications. Further, where underground springs throw up metal we ought
to continue
the digging we have begun, for this points to the particles having
been
detached from the main mass like a fragment from a body. In the
same way the thin scales of any metal adhering to stone or rock
are counted
among the good indications. Next, if the veins which are composed partly
of quartz, partly of clayey
or dry earth, descend one and all into the depths
of the earth
together, with their stringers, there is good hope of metal being
found; but if the stringers afterward do not appear, or little metallic
material is met with, the digging should not be given up until there is
nothing
remaining. Dark or black or horn or liver-coloured quartz is usually a good
sign;
white is sometimes good, sometimes no sign at all. But calc-spar,
showing itself in a
good indication; for it did not belong to the vein proper, but
to some stringer. Those kinds of stone which easily melt in fire, especially if they are
translucent
(fluorspar?), must be counted among the medium indications,
for if other
good indications are present they are good, but if no good
indications are
present, they give no useful significance. In the same way we ought to form
our judgment with regard to gems. Veins which at the hangingwall and
footwall have horn-coloured quartz or
marble, but in the middle clayey
earth, give some hope; likewise those
give hope in which the hangingwall
or footwall shows iron-rust coloured
earth, and in the middle greasy and
sticky earth; also there is hope
for those which have at the hanging or footwall
that kind of earth
which we call “soldiers' earth,” and in the middle black
earth or earth which looks as if burnt. The special indication of gold is
orpiment; of silver is bismuth and
sory, chalcitis,
misy,
of iron, iron rust. Gold and copper are equally indicated by chrysocolla and
azure; silver
and lead, by the lead. But, though miners rightly
call bismuth “the roof of
silver,” and though copper pyrites is the common
parent of
vitriol and
peculiar minerals, just as have
orpiment and
Now, just as certain vein materials give miners a favourable indication,
so also do the rocks through which the
way,
for sand discovered in a mine is reckoned among the good indications,
especially if it is very fine. In the same way schist, when it is of a
bluish or blackish colour, and
also limestone, of whatever colour it may be, is
a good sign for a
silver vein. There is a rock of another kind that is a good sign;
in it are scattered
tiny black stones from which tin is smelted; especially when
the whole
space between the veins is composed of this kind of rock. Very often indeed, this good kind of rock in conjunction with valuable
stringers contains within its folds the
it
descends vertically into the earth, the benefit belongs to that mine in
which it is seen first of all; if inclined, it benefits the other
neighbouring
minesAs a result the miner who is not ignorant of geometry can calculate
from
the other mines the depth at which the
metal
will wind its way through the rock into his mine. So much for these
matters.
I now come to the mode of working, which is varied and complex, for in
some places they dig crumbling ore, in others hard ore, in others a
harder
ore, and in others the hardest kind of ore. In the same way, in some places
the hangingwall rock is soft and
fragile, in others hard, in others harder, and
in still others of the
hardest sort. I call that ore “crumbling” which is com
posed of earth,
and of soft solidified juices; that ore “hard” which is composed
of metallic minerals and moderately hard stones, such as for the most
part
are those which easily melt in a fire of the first and second
orders, like lead
and similar materials. I call that ore “harder” when with those I have already
mentioned are combined various sorts of quartz, or stones which easily
melt
in fire of the third degree, or pyrites, or I call
that ore hardest, which is composed throughout the whole vein of
these hard
stones and compounds. The hanging or footwalls of a vein are hard, when
composed of rock in
which there are few stringers or seams; harder, in
which they are
fewer; hardest, in which they are fewest or none at all. When these are absent, the rock is quite devoid of water which softens
it. But the hardest rock of the hanging or footwall, however, is seldom as
hard as the harder class of ore.
Miners dig out crumbling ore with the pick alone.
When the metal
has not yet shown itself, they do not discriminate
between the hangingwall
and the veins; when it has once been found,
they work with the utmost care. For first of all they tear away the hangingwall rock separately from the
vein,
afterward with a pick they dislodge the crumbling vein from the
footwall
the ground. They break a hard vein loose from the footwall by blows with
a hammer
upon the first kind of iron tool
appropriate names, and with the same
tools they hew away the hard hanging
wall rock. They hew out the hangingwall rock in advance more frequently, the
rock
of the footwall more rarely; and indeed, when the rock of the footwall
resists iron tools, the rock of the hangingwall certainly cannot be
broken unless
it is allowable to shatter it by fire. With regard to the harder veins which are
tractable to iron tools, and
likewise with regard to the harder and hardest
kind of hangingwall
rock, they generally attack them with more powerful
iron tools, in
fact, with the fourth kind of iron tool, which are called by their
appropriate names; but if these are not ready to hand, they use two or
three iron tools of the first kind together. As for the hardest kind of metal
bearing vein, which in a measure
resists iron tools, if the owners of the
neighbouring mines give them
permission, they break it with fires. But if
these owners refuse them permission, then first of all they hew
out the rock of
the hangingwall, or of the footwall if it be less hard;
then they place timbers
set in hitches in the hanging or footwall, a
little above the vein, and from
the front and upper part, where the
vein is seen to be seamed with small
cracks, they drive into one of the
little cracks one of the iron tools which
I have mentioned; then in
each fracture they place four thin iron
blocks, and in order to hold
them more firmly, if necessary, they place
as many thin iron plates
back to back; next they place thinner iron
plates between each two iron
blocks, and strike and drive them by
turns with hammers, whereby the
vein rings with a shrill sound; and the
moment when it begins to be
detached from the hangingwall or footwall
rock, a tearing sound is
heard. As soon as this grows distinct the miners
hastily flee away; then a
great crash is heard as the vein is broken and torn,
and falls down. By this method they throw down a portion of a vein weigh
ing a
hundred pounds more or less. But if the miners by any other method
hew the hardest kind of vein which
is rich in metal, there remain certain
cone-shaped portions which can
be cut out afterward only with difficulty. As
for this knob of hard ore, if it is devoid of metal, or if they are
not allowed to
apply fire to it, they proceed round it by digging to
the right or left, because
it cannot be broken into by iron wedges
without great expense. Meantime,
while the workmen are carrying out the task they have
undertaken, the
depths of the earth often resound with sweet singing,
whereby they lighten a
toil which is of the severest kind and full of
the greatest dangers.
As I have just said, fire shatters the hardest rocks, but the method of its
application is not simpleFor if a vein held in the rocks cannot be hewn
low, a heap of dried logs is placed against the rock and fired; if the
drift or
tunnel is high, two heaps are necessary, of which one is
placed above the
other, and both burn until the fire has consumed them. This force does not
generally soften a large portion of the vein, but
only some of the surface. When the rock in the hanging or footwall can be worked by the iron tools
and the vein is so hard that it is not tractable to the same tools,
then the
walls are hollowed out; if this be in the end of the drift or
tunnel or above
or below, the vein is then broken by fire, but not by
the same method; for
if the hollow is wide, as many logs are piled into
it as possible, but if narrow,
only a few. By the one method the greater fire separates the vein more
completely
from the footwall or sometimes from the hangingwall, and by the
other,
the smaller fire breaks away less of the vein from the rock, because in
that case the fire is confined and kept in check by portions of the
rock which
surround the wood held in such a narrow excavation. Further, if the
excavation is low, only one pile of logs is placed in
it, if high, there are
two, one placed above the other, by which plan
the lower bundle being
kindled sets alight the upper one; and the fire
being driven by the draught
into the vein, separates it from the rock
which, however hard it may be, often
becomes so softened as to be the
most easily breakable of all. Applying this
principle, Hannibal, the Carthaginian General, imitating
the Spanish miners, Even
if a vein is a very wide one, as tin veins usually are, miners
excavate into the
small streaks, and into those hollows they put dry
wood and place amongst
them at frequent intervals sticks, all sides of
which are shaved down fan
shaped, which easily take light, and when
once they have taken fire com
municate it to the other bundles of
wood, which easily ignite.
A—KINDLED LOGS. B—STICKS SHAVED DOWN FAN-SHAPED.
C—TUNNEL.
While the heated veins and rock are giving forth a foetid vapour and the
shafts or tunnels are emitting fumes, the miners and other workmen do
not
go down in the mines lest the stench affect their health or
actually kill them,
as I will explain in greater detail when I come to
speak of the evils which
affect miners. The
suffocated, gives no one permission to break
veins or rock by fire in shafts or
tunnels where it is possible for the
poisonous vapour and smoke to permeate
the veins or stringers and pass
through into the neighbouring mines, which
have no hard veins or rock. As for that part of a vein or the surface of the
rock which the fire has
separated from the remaining mass, if it is overhead,
the miners
dislodge it with a crowbar, or if it still has some degree of hardness,
they thrust a smaller crowbar into the cracks and so break it down, but
if Thus broken off, the rock
tumbles down; or if it still remains, they
break it off with picks. Rock
and earth on the one hand, and metal and ore on the other, are
filled into
buckets separately and drawn up to the open air or to the
nearest tunnel. If the shaft is not deep, the buckets are drawn up by a machine turned by
men; if it is deep, they are drawn by machines turned by horses.
It often happens that a rush of water or sometimes stagnant air hinders
the mining; for this reason miners pay the greatest attention to these
matters, just as much as to digging, or they should do so. The water of the
veins and stringers and especially of vacant workings,
must be drained out
through the shafts and tunnels. Air, indeed, becomes stagnant both in
tunnels and in shafts; in a deep
shaft, if it be by itself, this occurs if it is
neither reached by a
tunnel nor connected by a drift with another shaft;
this occurs in a
tunnel if it has been driven too far into a mountain and no
shaft has
yet been sunk deep enough to meet it; in neither case can the
air move
or circulate. For this reason the vapours become heavy and
resemble mist, and they
smell of mouldiness, like a vault or some under
ground chamber
which has been completely closed for many years. This
suffices to prevent miners from continuing their work for long in
these places,
even if the mine is full of silver or gold, or if they do
continue, they cannot
breathe freely and they have headaches; this more
often happens if they
work in these places in great numbers, and bring
many lamps, which then
supply them with a feeble light, because the
foul air from both lamps and
men make the vapours still more heavy.
A small quantity of water is drawn from the shafts by machines of
different kinds which men turn or work. If so great a quantity has flowed
into one shaft as greatly to impede
mining, another shaft is sunk some
fathoms distant from the first, and
thus in one of them work and labour are
carried on without hindrance,
and the water is drained into the other, which
is sunk lower than the
level of the water in the first one; then by these
machines or by those
worked by horses, the water is drawn up into the drain
and flows out of
the shaft-house or the mouth of the nearest tunnel. But
when into the shaft of one mine, which is sunk more deeply, there
flows all
the water of all the neighbouring mines, not only from that
vein in which
the shaft is sunk, but also from other veins, then it
becomes necessary for a
large sump to be made to collect the water;
from this sump the water is
drained by machines which draw it through
pipes, or by ox-hides, about
which I will say more in the next book. The water which pours into the
tunnels from the veins and stringers and
seams in the rocks is carried
away in the drains.
Air is driven into the extremities of deep shafts and long tunnels by
powerful blowing machines, as I will explain in the following book,
which
will deal with these machines also. The outer air flows spontaneously into
the caverns of the earth, and
when it can pass through them comes out again. This, however, comes about in different ways, for in spring and summer it
flows into the deeper shafts, traverses the tunnels or drifts, and
finds its way
lowest tunnel and, meeting a shaft in
its course, turns aside to a higher tunnel
and passes out therefrom;
but in autumn and winter, on the other hand, it
enters the upper tunnel
or shaft and comes out at the deeper ones. This
change in the flow of air currents occurs in temperate regions at
the beginning
of spring and the end of autumn, but in cold regions at
the end of spring
and the beginning of autumn. But at each period, before the air regularly
assumes its own accustomed
course, generally for a space of fourteen days
it undergoes frequent
variations, now blowing into an upper shaft or
tunnel, now into a lower
one. But enough of this, let us now proceed to
what remains.
There are two kinds of shafts, one of the depth already described, of
which kind there are usually several in one mine; especially if the
mine is
entered by a tunnel and is metal-bearing. For when the first tunnel is
connected with the first shaft, two new
shafts are sunk; or if the inrush of
water hinders sinking, sometimes
three are sunk; so that one may take
the place of a sump and the work
of sinking which has been begun may be
continued by means of the
remaining two shafts; the same is done in the
case of the second tunnel
and the third, or even the fourth, if so many are
driven into a
mountain. The second kind of shaft is very deep, sometimes
as much as sixty,
eighty, or one hundred fathoms. These shafts continue
vertically toward the depths of the earth, and by
means of a hauling-rope
the broken rock and metalliferous ores are
drawn out of the mine; for which
reason miners call them vertical
shafts. Over these shafts are erected
machines by which water is extracted; when
they are above ground the
machines are usually worked by horses, but
when they are in tunnels, other
kinds are used which are turned by
water-power. Such are the shafts which
are sunk when a vein is rich in metal.
Now shafts, of whatever kind they may be, are supported in various
ways. If the vein is hard, and also the hanging and footwall rock, the shaft
does not require much timbering, but timbers are placed at intervals,
one end
of each of which is fixed in a hitch cut into the rock of the
hangingwall and
the other fixed into a hitch cut in the footwall. To these timbers are fixed
small timbers along the footwall, to which
are fastened the lagging and
ladders. The lagging is also fixed to the timbers, both to those which screen
off
the shaft on the ends from the vein, and to those which screen off the
rest of the shaft from that part in which the ladders are placed. The lagging
on the sides of the shaft confine the vein, so as to prevent
fragments of it
which have become loosened by water from dropping into
the shaft and
terrifying, or injuring, or knocking off the miners and
other workmen who
are going up or down the ladders from one part of the
mine to another. For
the same reason, the lagging between the ladders and the haulage-way
on
the other hand, confine and shut off from the ladders the fragments
of rock
which fall from the buckets or baskets while they are being
drawn up;
moreover, they make the arduous and difficult descent and
ascent to appear
less terrible, and in fact to be less dangerous.
If a vein is soft and the rock of the hanging and footwalls is weak,
a
closer structure is necessary; for this purpose timbers are joined together
in rectangular shapes and placed one after the other without a break. These
A—WALL PLATES. B—DIVIDERS. C—LONG END POSTS. D—END
PLATES.
timbers, which reach from the hangingwall
to the footwall, are fixed into corres
ponding square holes in the
timbers which lie along the hanging or footwall,
or the upper part of
the end of one and the lower part of the end of the other
are cut out
and one laid on the other. The great weight of these joined
timbers is sustained by stout beams
placed at intervals, which are deeply set
into hitches in the footwall
and hangingwall, but are inclined. In order that
these joined timbers may remain stationary, wooden wedges
or poles cut
from trees are driven in between the timbers and the vein
and the hanging
wall and the footwall; and the space which remains
empty is filled with loose
dirt. If the hanging and footwall rock is sometimes hard and sometimes soft,
and the vein likewise, solid joined timbers are not used, but timbers
are
placed at intervals; and where the rock is soft and the vein
crumbling,
carpenters put in lagging between them and the wall rocks,
and behind these
they fill with loose dirt; by this means they fill up
the void.
When a very deep shaft, whether vertical or inclined, is supported by
joined timbers, then, since they are sometimes of bad material and a
fall is
threatened, for the sake of greater firmness three or four
pairs of strong end
posts are placed between these, one pair on the
hangingwall side, the other
on the footwall side. To prevent them from falling out of position and to
make them firm and
substantial, they are supported by frequent end plates,
and in order
that these may be more securely fixed they are mortised into
the posts. Further, in whatever way the shaft may be timbered, dividers
are placed
upon the wall plates, and to these is fixed lagging, and this
marks off
and separates the ladder-way from the remaining part of the shaft. If a vertical shaft is a very deep one, planks are laid upon the timbers by
the
side of the ladders and fixed on to the timbers, in order that the
men who are
going up or down may sit or stand upon them and rest when
they are tired. To prevent danger to the shovellers from rocks which, after being drawn up
from so deep a shaft fall down again, a little above the bottom of the
shaft
small rough sticks are placed close together on the timbers, in
such a way as
to cover the whole space of the shaft except the
ladder-way. A hole,
however, is left in this structure near the footwall, which is
kept open so that
there may be one opening to the shaft from the
bottom, that the buckets
full of the materials which have been dug out
may be drawn from the
shaft through it by machines, and may be returned
to the same place again
empty; and so the shovellers and other workmen,
as it were hiding beneath
this structure, remain perfectly safe in the
shaft.
In mines on one vein there are driven one, two, or sometimes three
or
more tunnels, always one above the other. If the vein is solid and
hard, and likewise the hanging and footwall
rock, no part of the tunnel
needs support, beyond that which is
required at the mouth, because at that
spot there is not yet solid
rock; if the vein is soft, and the hanging and
footwall rock are
likewise soft, the tunnel requires frequent strong timbering,
which is
provided in the following way. First, two dressed posts are erected
and set into the tunnel floor,
which is dug out a little; these are of medium
touch the
top of the tunnel; then upon them is placed a smaller dressed cap,
which is mortised into the heads of the posts: at the bottom, other
small
timbers, whose ends are similarly squared, are mortised into the
posts. At
each interval of one and a half fathoms, one of these sets is
erected; each one
of these the miners call a “little
doorway,” because it opens a certain amount
of passage way; and
indeed, when necessity requires it, doors are fixed to the
timbers of
each little doorway so that it can be closed. Then lagging of
planks or of poles is placed upon the caps lengthwise,
so as to reach from one
set of timbers to another, and is laid along
the sides, in case some portion of
the body of the mountain may fall,
and by its bulk impede passage or crush
persons coming in or out. Moreover, to make the timbers remain stationary,
wooden pegs are driven
between them and the sides of the tunnel. Lastly,
if rock or earth are carried out in wheelbarrows, planks joined
together are
laid upon the sills; if the rock is hauled out in trucks,
then two timbers
three-quarters of a foot thick and wide are laid on
the sills, and, where they
join, these are usually hollowed out so that
in the hollow, as in a road, the iron
pin of the truck may be pushed
along; indeed, because of this pin in the
groove, the truck does not
leave the worn track to the left or right. Beneath
the sills are the drains through which the water flows away.
A—POSTS. B—CAPS. C—SILLS. D—DOORS. E—LAGGING.
F—DRAINS.
Miners timber drifts in the same way as tunnels.
These do not, however,
require sill-pieces, or drains; for the broken
rock is not hauled very far, nor does
the water have far to flow. If the vein above is metal-bearing, as it sometimes is
drifts that have already been driven, other drifts are driven again
and again until that part of the vein is reached which does not yield
metal. The timbering of these openings is done as follows: stulls are set at
intervals into hitches in the hanging and footwall, and upon them
smooth poles are laid continuously; and that they may be able to
bear the weight, the stulls are generally a foot and a half thick. After the
ore has been taken out and the mining of the vein is being
done elsewhere,
the rock then broken, especially if it cannot be taken
away without great
difficulty, is thrown into these openings among the
timber, and the carriers
of the ore are saved toil, and the owners save
half the expense. This then,
generally speaking, is the method by which everything
relating to the
timbering of shafts, tunnels, and drifts is carried
out.
All that I have hitherto written is in part peculiar to
and in part common to all
kinds of veins; of what follows, part is specially
applicable to But first I will
describe how Where torrents, rivers, or
streams have by inundations washed away part
of the slope of a mountain or
a hill, and have disclosed a
and narrow, and then wider, for nearly all the
vein should be hewn away; and
when this tunnel has been driven further,
a shaft which supplies air should be
sunk in the mountain or hill, and
through it from time to time the ore, earth,
and rock can be drawn up
at less expense than if they be drawn out through the
very great length
of the tunnel; and even in those places to which the tunnel
does not
yet reach, miners dig shafts in order to open a
they conjecture must lie
beneath the soil. In this way, when the upper
layers are removed, they dig through rock
sometimes of one kind and colour,
sometimes of one kind but different
colours, sometimes of different kinds but
of one colour, and, lastly,
of different kinds and different colours. The thickness
of rock, both of each single stratum and of all combined,
is uncertain, for
the whole of the strata are in some places twenty
fathoms deep, in others
more than fifty; individual strata are in some
places half a foot thick; in others,
one, two, or more feet; in others,
one, two, three, or more fathoms. For
example, in those districts which lie at the foot of the Harz
mountains,
there are many different coloured strata, covering a copper
When
the soil has been stripped, first of all is disclosed a stratum which
is red, but of a dull shade and of a thickness of twenty, thirty, or
five and
thirty fathoms. Then there is another stratum, also red, but of a light
shade, which has
usually a thickness of about two fathoms. Beneath this is a
stratum of ash-coloured clay nearly a fathom thick,
which, although it is
not metalliferous, is reckoned a vein. Then follows a third stratum,
which is ashy, and about three fathoms
thick. Beneath this lies a vein
of ashes to the thickness of five fathoms, and
these ashes are mixed with
rock of the same colour. Joined to the last, and underneath, comes a
stratum, the fourth in
number, dark in colour and a foot thick. Under this
comes the fifth stratum, of a pale or yellowish colour, two
feet thick; under-
thick. Afterward occurs the seventh stratum, likewise of dark colour, but
still
darker than the last, and two feet thick. This is followed by an eighth
stratum, ashy, rough, and a foot thick. This kind, as also the others,
is sometimes distinguished by stringers
of the stone which easily melts in
fire of the second order. Beneath this is another ashy rock, light in
weight, and five feet thick. Next to this comes a lighter ash-coloured
one, a foot thick; beneath
this lies the eleventh stratum, which is dark and
very much like the
seventh, and two feet thick. Below the last is
a twelfth stratum of a whitish colour and soft, also
two feet thick; the
weight of this rests on a thirteenth stratum, ashy
and one foot thick, whose
weight is in turn supported by a fourteenth
stratum, which is blackish and
half a foot thick. There follows this, another stratum of black colour,
likewise half a
foot thick, which is again followed by a sixteenth stratum
still
blacker in colour, whose thickness is also the same. Beneath this, and
last of all, lies the cupriferous stratum, black
coloured and schistose, in which
there sometimes glitter scales of
gold-coloured pyrites in the very thin sheets,
which, as I said
elsewhere, often take the forms of various living things.
The miners mine out a
driving a low
tunnel in it, and if the nature of the work and place permit, they
sink
also a shaft in order to discover whether there is a second vein beneath
the first one; for sometimes beneath it there are two, three, or more
similar
metal-bearing veins, and these are excavated in the same way
laterally and
longitudinally. They generally mine
usually bind
on themselves small wooden cradles. For this reason, this
particular class of miners, in order to use their
iron tools, are obliged to bend
their necks to the left, not
infrequently having them twisted. Now these
veins also sometimes divide, and where these parts re-unite,
ore of a richer and
a better quality is generally found; the same thing
occurs where the stringers,
of which they are not altogether devoid,
join with them, or cut them crosswise,
or divide them obliquely. To prevent a mountain or hill, which has in
this way been undermined,
from subsiding by its weight, either some natural
pillars and arches
are left, on which the pressure rests as on a foundation, or
timbering
is done for support. Moreover, the materials which are dug out
and which are devoid of metal
are removed in bowls, and are thrown back,
thus once more filling the
caverns.
Next, as to
These are dug by a somewhat different
method, for when one of these
shows some metal at the top of the ground,
first of all one shaft is
sunk; then, if it is worth while, around this one many
shafts are sunk
and tunnels are driven into the mountain. If a torrent or
spring has torn fragments of metal from such a vein, a
tunnel is first driven
into the mountain or hill for the purpose of
searching for the ore; then
when it is found, a vertical shaft is sunk
in it. Since the whole mountain, or
more especially the whole hill, is
undermined, seeing that the whole of it is
composed of ore, it is
necessary to leave the natural pillars and arches, or the
place is
timbered. But sometimes when a vein is very hard it is broken by
fire, whereby it
happens that the soft pillars break up, or the timbers are
burnt away,
and the mountain by its great weight sinks into itself, and then
the
shaft buildings are swallowed up in the great subsidence. Therefore,
about a
ject to this kind of ruin, through which the materials that are
excavated may
be carried out, not only while the pillars and
underpinnings still remain whole
and solid, but also after the supports
have been destroyed by fire and have
fallen. Since ore which has thus fallen must necessarily be broken by fire,
new
shafts through which the smoke can escape must be sunk in the abyss.
At those places where stringers intersect, richer ore is generally obtained
from the mine; these stringers, in the case of tin mines, sometimes
have in
them black stones the size of a walnut. If such a vein is found in a plain,
as not infrequently happens in the
case of iron, many shafts are sunk, because
they cannot be sunk very
deep. The work is carried on by this method
because the miners cannot drive a
tunnel into a level plain of this kind.
There remain the stringers in which gold alone is sometimes found,
in
the vicinity of rivers and streams, or in swamps. If upon the soil being
removed, many of these are found, composed of
earth somewhat baked and
burnt, as may sometimes be seen in clay pits,
there is some hope that gold
may be obtained from them, especially if
several join together. But the
very point of junction must be pierced, and the length and width
searched
for ore, and in these places very deep shafts cannot be
sunk.
I have completed one part of this book, and now come to the other, in
which I will deal with the art of surveying. Miners measure the solid
that their workmen may not
encroach on other people's possessions. The
surveyor either measures the interval not yet wholly dug through,
which
lies between the mouth of a tunnel and a shaft to be sunk to that
depth, or
between the mouth of a shaft and the tunnel to be driven to
that spot which
lies under the shaft, or between both, if the tunnel is
neither so long as to
reach to the shaft, nor the shaft so deep as to
reach to the tunnel; and thus
on both sides work is still to be done. Or in some cases, within the tunnels
and drifts, are to be fixed the
boundaries of the meers, just as the
has determined the
boundaries of the same meers above ground.
Each method of surveying depends on the measuring of triangles.
A
small triangle should be laid out, and from it calculations must be
made
regarding a larger one. Most particular care must be taken that we do not
deviate at all from a
correct measuring; for if, at the beginning, we are drawn Now these triangles are of many shapes, since shafts differ among themselves
and are not all sunk by one and the same method into the depths of the
earth, nor do the slopes of all mountains come down to the valley or
plain in
the same manner. For if a shaft is vertical, there is a triangle with a right
angle,
which the Greeks call
inequalities of the mountain slope, has either two
equal sides or three unequal
sides. The Greeks call the former
a right angle triangle cannot have three
equal sides. If a shaft is inclined
and sunk in the same vein in which the tunnel is
driven, a triangle is likewise
made with a right angle, and this again,
according to the various inequalities
of the mountain slope, has either
two equal or three unequal sides. But if
a shaft is inclined and is sunk in one vein, and a tunnel is
driven in
another vein, then a triangle comes into existence which has
either an obtuse
angle or all acute angles. The former the Greeks call
equal sides, but in accordance
with the different mountain slopes has either
two equal sides or three
unequal sides. That triangle which has all acute
angles in accordance with the
different mountain slopes has either three equal
sides, which the
Greeks call
unequal sides.
The surveyor, as I said, employs his art when the owners of the mines
desire to know how many fathoms of the intervening ground require to be
dug; when a tunnel is being driven toward a shaft and does not yet
reach
it; or when the shaft has not yet been sunk to the depth of the
bottom of the
tunnel which is under it; or when neither the tunnel
reaches to that point,
nor has the shaft been sunk to it. It is of importance that miners should
know how many fathoms remain from
the tunnel to the shaft, or from the
shaft to the tunnel, in order to
calculate the expenditure; and in order that
the owners of a
metal-bearing mine may hasten the sinking of a shaft and
the excavation
of the metal, before the tunnel reaches that point and the
tunnel
owners excavate part of the metal by any right of their own; and on
the
other hand, it is important that the owners of a tunnel may similarly
hasten their driving before a shaft can be sunk to the depth of a
tunnel, so
that they may excavate the metal to which they will have a
right.
The surveyor, first of all, if the beams of the shaft-house do not give him
the opportunity, sets a pair of forked posts by the sides of the shaft
in such
a manner that a pole may be laid across them. Next, from the pole he lets
down into the shaft a cord with a weight
attached to it. Then he stretches a
second cord, attached to the upper end of the first
cord, right down along the
slope of the mountain to the bottom of the
mouth of the tunnel, and fixes it to
the ground. Next, from the same pole not far from the first cord, he lets
down a
third cord, similarly weighted, so that it may intersect the second
cord, which descends obliquely. Then, starting from that point where the
third cord cuts the second cord
which descends obliquely to the mouth of the
tunnel, he measures the
second cord upward to where it reaches the end of
A—UPRIGHT FORKED POSTS. B—POLE OVER THE POSTS. C—SHAFT.
D—FIRST CORD.
E—WEIGHT OF FIRST CORD. F—SECOND CORD.
G—SAME FIXED GROUND. H—HEAD
OF FIRST CORD. I—MOUTH OF
TUNNEL. K—THIRD CORD. L—WEIGHT OF THIRD CORD.
M—FIRST
SIDE MINOR TRIANGLE. N—SECOND SIDE MINOR TRIANGLE. O—THIRD SIDE
MINOR TRIANGLE. P—THE MINOR TRIANGLE.Afterward, starting again from that point where the third cord intersects the
second cord, he measures the straight space which lies between that
point
and the opposite point on the first cord, and in that way forms
the minor
triangle, and he notes this second side of the minor triangle
in the same way as
before. Then, if it is necessary, from the angle formed by the first cord and
the second side of the minor triangle, he measures upward to the end of
the
first cord and also makes a note of this third side of the minor
triangle. The
third side of the minor triangle, if the shaft is vertical or
inclined and is sunk
on the same vein in which the tunnel is driven,
will necessarily be the same
length as the third cord above the point
where it intersects the second cord;
and so, as often as the first side
of the minor triangle is contained in the
length of the whole cord
which descends obliquely, so many times the length
of the second side
of the minor triangle indicates the distance between the
mouth of the
tunnel and the point to which the shaft must be sunk; and
similarly, so
many times the length of the third side of the minor triangle
gives the
distance between the mouth of the shaft and the bottom of the
tunnel.
When there is a level bench on the mountain slope, the surveyor first
measures across this with a measuring-rod; then at the edges of this
bench
he sets up forked posts, and applies the principle of the
triangle to the two
sloping parts of the mountain; and to the fathoms
which are the length of
that part of the tunnel determined by the
triangles, he adds the number
of fathoms which are the width of the
bench. But if sometimes the
mountain side stands up, so that a cord cannot run
down from the shaft to
the mouth of the tunnel, or, on the other hand,
cannot run up from the
mouth of the tunnel to the shaft, and,
therefore, one cannot connect them in
a straight line, the surveyor, in
order to fix an accurate triangle, measures the
mountain; and going
downward he substitutes for the first part of the cord
a pole one
fathom long, and for the second part a pole half a fathom
long. Going upward, on the contrary, for the first part of the cord he
sub
stitutes a pole half a fathom long, and for the next part, one
a whole fathom
long; then where he requires to fix his triangle he adds
a straight line to
these angles.
To make this system of measuring clear and more explicit, I will proceed
by describing each separate kind of triangle. When a shaft is vertical or
inclined, and is sunk in the same vein on
which the tunnel is driven, there
is created, as I said, a triangle
containing a right angle. Now if the minor
triangle has the two sides equal, which, in accordance
with the numbering
used by surveyors, are the second and third sides,
then the second and third
sides of the major triangle will be equal;
and so also the intervening
distances will be equal which lie between
the mouth of the tunnel and the
bottom of the shaft, and which lie
between the mouth of the shaft and the
bottom of the tunnel. For example, if the first side of the minor triangle is
seven feet long
and the second and likewise the third sides are five feet, and
seven feet, that is 117 fathoms and five feet,
then the intervening space, of
course, whether the whole of it has been
already driven through or has yet
to be driven, will be one hundred
times five feet, which makes eighty-three
fathoms and two feet. Anyone with this example of proportions will be
able to construct the
major and minor triangles in the same way as I have
done, if there be
the necessary upright posts and cross-beams. When a shaft is
vertical the triangle is absolutely upright; when it is
inclined and is sunk on
the same vein in which the tunnel is driven, it
is inclined toward one side.
A TRIANGLE HAVING A RIGHT ANGLE AND TWO EQUAL SIDES.
Therefore, if a
tunnel has been driven into the mountain for sixty fathoms,
there
remains a space of ground to be penetrated twenty-three fathoms and
two
feet long; for five feet of the second side of the major triangle, which
lies above the mouth of the shaft and corresponds with the first side
of the
minor triangle, must not be added. Therefore, if the shaft has been sunk
in the middle of the head meer, a
tunnel sixty fathoms long will reach
to the boundary of the meer only
when the tunnel has been extended a
further two fathoms and two feet;
but if the shaft is located in the middle of
an ordinary meer, then the
boundary will be reached when the tunnel has been
driven a further
length of nine fathoms and two feet. Since a tunnel, for
every one hundred fathoms of length, rises in grade
one fathom, or at all
events, ought to rise as it proceeds toward the
shaft, one more fathom must
always be taken from the depth allowed to
the shaft, and one added to the
length allowed to the tunnel. Proportionately, because a tunnel fifty
fathoms long is raised half a
fathom, this amount must be taken from the
depth of the shaft and added
to the length of the tunnel. In the same way
if a tunnel is one hundred or fifty fathoms shorter or
longer, the same propor
tion also must be taken from the depth of
the one and added to the length
of the other. For this reason, in the case mentioned above, half a fathom
and a little
more must be added to the distance to be driven through, so
that there
remain twenty-three fathoms, five feet, two palms, one and a half
digits and a fifth of a digit; that is, if even the minutest
proportions are
carried out; and surveyors do not neglect these without
good cause. Similarly, if the shaft is seventy fathoms deep, in order that it may reach
to
the bottom of the tunnel, it still must be sunk a further depth of
thirteen
fathoms and two feet, or rather twelve fathoms and a half, one
foot, two
digits, and four-fifths of half a digit. And in this instance five feet must be
deducted from the reckoning,
because these five feet complete the third side
of the minor triangle,
which is above the mouth of the shaft, and from its
and the fifth part of half a digit. But if the tunnel has been driven to a
point where it is under the
shaft, then to reach the roof of the tunnel the
shaft must still be
sunk a depth of eleven fathoms, two and a half feet, one
palm, two
digits, and four-fifths of half a digit.
If a minor triangle is produced of the kind having three unequal sides,
then the sides of the greater triangle cannot be equal; that is, if the
first
side of the minor triangle is eight feet long, the second six
feet long, and the
third five feet long, and the cord along the side of
the greater triangle, not
to go too far from the example just given, is
one hundred and one times
eight feet, that is, one hundred and
thirty-four fathoms and four feet, the
distance which lies between the
mouth of the tunnel and the bottom of the
shaft will occupy one hundred
times six feet in length, that is, one hundred
fathoms. The distance between the mouth of the shaft and the bottom of the
tunnel
is one hundred times five feet, that is, eighty-three fathoms and two feet.
And so, if the tunnel is eighty-five fathoms long, the remainder to be driven
into the mountain is fifteen fathoms long, and here, too, a correction
in
measurement must be taken from the depth of the shaft and added to
the
length of the tunnel; what this is precisely, I will pursue no
further, since
everyone having a small knowledge of arithmetic can work
it out. If the
shaft is sixty-seven fathoms deep, in order that it may reach the
bottom of
the tunnel, the further distance required to be sunk amounts
to sixteen
fathoms and two feet.
A TRIANGLE HAVING A RIGHT ANGLE AND THREE UNEQUAL SIDES.
The surveyor employs this same method in measuring the mountain,
whether
the shaft and tunnel are on one and the same vein, whether the vein
is
vertical or inclined, or whether the shaft is on the principal vein and the
tunnel
on a transverse vein descending vertically to the depths of the
earth; in the
latter case the excavation is to be made where the
transverse vein cuts the
vertical vein. If the principal vein descends on an incline and the cross-vein
descends
vertically, then a minor triangle is created having one obtuse angle or
all three angles acute. If the minor triangle has one angle obtuse and the two
sides which are
the second and third are equal, then the second and third
sides of the
major triangle will be equal, so that if the first side of the minor
triangle is nine feet, the second, and likewise the third, will be five
feet. Then
the first side of the major triangle will be one hundred and one
times nine
feet, or one hundred and fifty-one and one-half fathoms, and
each of the
other sides of the major triangle will be one hundred times
five feet, that is,
eighty-three fathoms and two feet. But when the first shaft is inclined,
inclined, and one
always following the other. Therefore, if a tunnel is seventy
seven fathoms long, it will reach
to the middle of the bottom of a shaft when
six fathoms and two feet
further have been sunk. But if all such inclined
shafts are seventy-six fathoms deep, in order
that the last one may reach
the bottom of the tunnel, a depth of seven
fathoms and two feet remains to
be sunk.
TRIANGLE HAVING AN OBTUSE ANGLE AND TWO EQUAL SIDES.
If a minor triangle is made which has an obtuse angle and three unequal
sides, then again the sides of the large triangle cannot be equal. For
example, if the first side of the minor triangle is six feet long,
the second
three feet, and the third four feet, and the cord along the
side of the greater
triangle one hundred and one times six feet, that
is, one hundred and one
fathoms, the distance between the mouth of the
tunnel and the bottom of
the last shaft will be a length one hundred
times three feet, or fifty fathoms;
but the depth that lies between the
mouth of the first shaft and the bottom of
the tunnel is one hundred
times four feet, or sixty-six fathoms and four feet. Therefore, if a tunnel is forty-four fathoms long, the remaining distance to
be driven is six fathoms. If the shafts are fifty-eight fathoms deep, the
newest will touch the
bottom of the tunnel when eight fathoms and four
feet have been
sunk.
TRIANGLE HAVING AN OBTUSE ANGLE AND THREE UNEQUAL SIDES.
If a minor triangle is produced which has all its angles acute and its
three sides equal, then necessarily the second and third sides of the
minor
triangle will be equal, and likewise the sides of the major
triangle frequently
referred to will be equal. Thus if each side of the minor triangle is six feet
long, and the cord
measurement for the side of the major triangle is one
hundred and one
times six feet, that is, one hundred and one fathoms, then
both the
distances to be dug will be one hundred fathoms. And thus if the
tunnel is ninety fathoms long, it will reach the middle
of the bottom of the
last shaft when ten fathoms further have been
driven. If the shafts are
it is sunk a further depth of five
fathoms.
A TRIANGLE HAVING ALL ITS ANGLES ACUTE AND ITS THREE SIDES EQUAL.
If a triangle is made which has all its angles acute, but only two sides
equal, namely, the first and third, then the second and third sides are
not
equal; therefore the distances to be dug cannot be equal. For example, if
the first side of the minor triangle is six feet long,
and the second is four feet,
and the third is six feet, and the cord
measurement for the side of the major
triangle is one hundred and one
times six feet, that is, one hundred and one
fathoms, then the distance
between the mouth of the tunnel and the bottom of
the last shaft will
be sixty-six fathoms and four feet. But the distance from the
mouth of the first shaft to the bottom of the
tunnel is one hundred fathoms. So if the tunnel is sixty fathoms long, the remaining distance to be driven
into the mountain is six fathoms and four feet. If the shaft is ninety-seven
fathoms deep, the last one will reach the
bottom of the tunnel when a further
depth of three fathoms has been
sunk.
TRIANGLE HAVING ALL ITS ANGLES ACUTE AND TWO SIDES EQUAL, A, B, UNEQUAL SIDE
C.
If a minor triangle is produced which has all its angles acute, but its
three sides unequal, then again the distances to be dug cannot be
equal. For example, if the first side of the minor triangle is seven feet long, the
second side is four feet, and the third side is six feet, and the cord
measure
ment for the side of the major triangle is one hundred and
one times seven
feet or one hundred and seventeen fathoms and four
feet, the distance
between the mouth of the tunnel and the bottom of
the last shaft will be
four hundred feet or sixty-six fathoms, and the
depth between the mouth of
the first shaft and the bottom of the tunnel
will be one hundred fathoms. Therefore, if a tunnel is fifty fathoms long, it will reach the middle of the
bottom of the newest shaft when it has been driven sixteen fathoms and
four
feet further. But if the shafts are then ninety-two fathoms deep, the last
eight fathoms.
A TRIANGLE HAVING ALL ITS ANGLES ACUTE AND ITS THREE SIDES UNEQUAL.
This is the method of the surveyor in measuring the mountain, if the
principal vein descends inclined into the depths of the earth or the
transverse
vein is vertical. But if they are both inclined, the surveyor uses the same
method, or he
measures the slope of the mountain separately from the slope
of the
shaft. Next, if a transverse vein in which a tunnel is driven does not
cut the
principal vein in that spot where the shaft is sunk, then it is necessary
for the starting point of the survey to be in the other shaft in which
the
transverse vein cuts the principal vein. But if there be no shaft on that spot
where the outcrop of the
transverse vein cuts the outcrop of the principal
vein, then the
surface of the ground which lies between the shafts must
be measured,
or that between the shaft and the place where the outcrop of
the one
vein intersects the outcrop of the other.
Some surveyors, although they use three cords, nevertheless ascertain
only the length of a tunnel by that method of measuring, and determine
the depth of a shaft by another method; that is, by the method by
which cords are re-stretched on a level part of the mountain or in
a valley, or in flat fields, and are measured again. Some, however, do
not employ this method in surveying the depth of a
shaft and the
length of a tunnel, but use only two cords, a graduated
hemicycle
rod half
a fathom long. They suspend in the shaft one cord, fastened
from the upper pole and
weighted, just as the others do. Fastened to the
upper end of this cord, they stretch another right down
the slope of the mountain
to the bottom of the mouth of the tunnel and
fix it to the ground. Then to
the upper part of this second cord they apply on its lower side
the broad part
of a hemicycle. This consists of half a circle, the outer margin of which is
covered
with wax, and within this are six semi-circular lines. From the
there proceed straight lines
converging toward the centre of the hemicycle;
these mark the middles
of intervening spaces lying between other straight lines
which extend
to the fourth semi-circular line. But all lines whatsoever, from
the waxed margin up to the fourth line,
whether they go beyond it or not,
correspond with the graduated lines
which mark the minor spaces of a rod. Those which go beyond the fourth line correspond with the lines marking
A—WAXED SEMICIRCLE OF THE HEMICYCLE. B—SEMICIRCULAR LINES.
C—STRAIGHT
LINES. D—LINE MEASURING THE HALF. E—LINE
MEASURING THE WHOLE. F—TONGUE.
middle of the
intervening space which lies between the others. The
straight lines, which run from the fifth to the sixth semi-circular
line, show
nothing further. Nor does the line which measures the half, show anything
when it has
already passed from the sixth straight line to the base of the
hemicycle. When the hemicycle is applied to the cord, if its tongue indicates
the
sixth straight line which lies between the second and third semi-circular
lines, the surveyor counts on the rod six lines which separate the
minor
spaces, and if the length of this portion of the rod be taken
from the second
cord, as many times as the cord itself is half-fathoms
long, the remaining
length of cord shows the distance the tunnel must
be driven to reach under
the shaft. But if he sees that the tongue has gone so far that it marks the
sixth
line between the fourth and fifth semi-circular lines, he counts six lines
which separate the major spaces on the rod; and this entire space is
deducted
from the length of the second cord, as many times as the
number of whole
fathoms which the cord contains; and then, in like
manner, the remaining
length of cord shows us the distance the tunnel
must be driven to reach
under the shaft.
STRETCHED CORDS: A—FIRST CORD. B—SECOND CORD. C—THIRD CORD.
D—TRIANGLE.
Both these surveyors, as well as the others, in the first place make use
of the haulage rope. These they measure by means of others made of linden
bark, because the
latter do not stretch at all, while the former become very
slack. These cords they stretch on the surveyor's field, the first one to
represent the parts of mountain slopes which descend obliquely. Then the
second cord, which represents the length of the tunnel to be
driven to reach
the shaft, they place straight, in such a direction
that one end of it can touch
the lower end of the first cord; then they
similarly lay the third cord straight,
and in such a direction that its
upper end may touch the upper end of
the first cord, and its lower end
the other extremity of the second cord, and
thus a triangle is formed. This third cord is measured by the instrument
with the index, to
determine its relation to the perpendicular; and the length
of this
cord shows the depth of the shaft.
Some surveyors, to make their system of measuring the depth of a shaft
more certain, use five stretched cords: the first one descending
obliquely;
two, that is to say the second and third, for ascertaining
the length of the
tunnel; two for the depth of the shaft; in which way
they form a quadrangle
divided into two equal triangles, and this tends
to greater accuracy.
STRETCHED CORDS: A—FIRST. B—SECOND. B—THIRD.
C—FOURTH. C—FIFTH.
D—QUADRANGLE.
These systems of measuring the depth of a shaft and the length of a
tunnel, are accurate when the vein and also the shaft or shafts go down
to the The same is true
when a tunnel runs straight on to a shaft. But when each of them bends
now in this, now in that direction, if they
have not been completely driven
and sunk, no living man is clever
enough to judge how far they are deflected
from a straight course. But if the whole of either one of the two has been ex
cavated its
full distance, then we can estimate more easily the length of one,
or
the depth of the other; and so the location of the tunnel, which is below
a newly-started shaft, is determined by a method of surveying which I
will
describe. First of all a tripod is fixed at the mouth of the tunnel, and likewise at
the mouth of the shaft which has been started, or at the place where
the shaft will
be started. The tripod is made of three stakes fixed to the ground, a small
rectangular board being placed upon the stakes and fixed to them, and
on
this is set a compass. Then from the lower tripod a weighted cord is let
down perpendicularly
to the earth, close to which cord a stake is fixed in the
ground. To this stake another cord is tied and drawn straight into the tunnel
to
a point as far as it can go without being bent by the hangingwall or the
footwall of the vein. Next, from the cord which hangs from the lower tripod,
a third cord
likewise fixed is brought straight up the sloping side of the
mountain
to the stake of the upper tripod, and fastened to it. In order that
the measuring of the depth of the shaft may be more
certain, the third cord
should touch one and the same side of the cord
hanging from the lower tripod
which is touched by the second
cord—the one which is drawn into the tunnel. All this having been correctly carried out, the surveyor, when at length
the cord which has been drawn straight into the tunnel is about to be
bent
by the hangingwall or footwall, places a plank in the bottom of
the tunnel
and on it sets the orbis, an instrument which has an
indicator peculiar
to itself. This instrument, although it also has waxed circles, differs from the
other, which I have described in the third book. But by both these
instruments, as well as by a rule and a square, he
determines whether the
stretched cords reach straight to the extreme
end of the tunnel, or whether
they sometimes reach straight, and are
sometimes bent by the footwall or
hangingwall. Each instrument is divided into parts, but the compass into
twenty-four
parts, the orbis into sixteen parts; for first of all it is divided
into four principal parts, and then each of these is again divided into
four. Both have waxed circles, but the compass has seven circles, and the orbis
only five circles. These waxed circles the surveyor marks, whichever instru
ment he
uses, and by the succession of these same marks he notes any
change in
the direction in which the cord extends. The orbis has an open
ing running from its outer edge as far as the
centre, into which opening he
puts an iron screw, to which he binds the
second cord, and by screwing it into
the plank, fixes it so that the
orbis may be immovable. He takes care
to prevent the second cord, and afterward the others which
are put up,
from being pulled off the screw, by employing a heavy iron,
into an opening
of which he fixes the head of the screw. In the case of the compass, since
it has no opening, he merely places it
by the side of the screw. That the
instrument does not incline forward or backward, and in that
way the
instrument a standing plummet level, the
tongue of which, if the instrument
is level, indicates no numbers, but
the point from which the numbers start.
COMPASS. A, B, C, D, E, F, G ARE THE SEVEN WAXED CIRCLES.
When the surveyor has carefully observed each separate angle of the
tunnel and has measured such parts as he ought to measure, then he lays
them out in the same way on the surveyor's field
no less
carefully observes each separate angle and measures them. First of
all, to each angle, according as the calculation of his
triangle and his art
require it, he lays out a straight cord as a line. Then he stretches a cord at
A, B, C, D, E—FIVE WAXED CIRCLES OF THE
F—OPENING OF SAME.
G—SCREW. H—PERFORATED IRON.
A—LINES OF THE ROD WHICH SEPARATE MINOR SPACES. B—LINES OF THE
ROD WHICH SEPARATE MAJOR SPACES.
may reach
the end of the straight cord; then he stretches a third cord
A—STANDING PLUMMET LEVEL. B—TONGUE. C—LEVEL AND TONGUE.
the upper end of the second cord, and with its
lower end the last end of the
first cord. The length of the third cord shows the depth of the shaft, as I
said
before, and at the same time that point on the tunnel to which the shaft
will reach when it has been sunk.
If one or more shafts reach the tunnel through intermediate drifts and
shafts, the surveyor, starting from the nearest which is open to the
air,
measures in a shorter time the depth of the shaft which requires
to be sunk,
than if he starts from the mouth of the tunnel. First of all he measures
that space on the surface which lies between
the shaft which has been sunk
and the one which requires to be sunk. Then he measures the incline of all
the shafts which it is necessary to
measure, and the length of all the drifts
with which they are in any
way connected to the tunnel. Lastly, he
measures part of the tunnel; and when all this is properly
done, he demon
strates the depth of the shaft and the point in the
tunnel to which the shaft
will reach. But sometimes a very deep straight shaft requires to be sunk
at the same
place where there is a previous inclined shaft, and to the same
depth,
in order that loads may be raised and drawn straight up by machines.
Those machines on the surface are turned by horses; those inside the earth,
by the same means, and also by water-power. And so, if it becomes
necessary to sink such a shaft, the surveyor first
of all fixes an iron screw
in the upper part of the old shaft, and from
the screw he lets down a cord
as far as the first angle, where again he
fixes a screw, and again lets down the
cord as far as the second angle;
this he repeats again and again until the
cord reaches to the bottom of
the shaft. Then to each angle of the cord he
applies a hemicycle, and marks the
waxed semi-circle according to the lines
which the tongue indicates,
and designates it by a number, in case it should be
moved; then he
measures the separate parts of the cord with another cord
made of
linden bark. Afterward, when he has come back out of the shaft,
he goes away and
transfers the markings from the waxed semi-circle of the
hemicycle to
an orbis similarly waxed. Lastly, the cords are stretched on the
surveyor's field, and he measures
the angles, as the system of measuring by
triangles requires, and
ascertains which part of the footwall and which
part of the hangingwall
rock must be cut away in order that the shaft may
descend straight. But if the surveyor is required to show the owners of the
mine, the spot
in a drift or a tunnel in which a shaft needs to be raised
from the
bottom upward, that it should cut through more quickly, he
begins
measuring from the bottom of the drift or tunnel, at a point
beyond the
spot at which the bottom of the shaft will arrive, when it has been
sunk. When he has measured the part of the drift or tunnel up to the first
shaft which connects with an upper drift, he measures the incline of
this
shaft by applying a hemicycle or orbis to the cord. Then in a like manner
he measures the upper drift and the incline shaft
which is sunk therein
toward which a raise is being dug, then again all
the cords are stretched in
the surveyor's field, the last cord in such
a way that it reaches the first, and
then he measures them. From this measurement is known in what part
vein remain
to be broken through in order that the shaft may be connected.
I have described the first reason for surveying; I will now describe
another. When one vein comes near another, and their owners are different
persons
who have late come into possession, whether they drive a tunnel
or a
drift, or sink a shaft, they may encroach, or seem to encroach, without
any lawful right, upon the boundaries of the older owners, for which
reason
the latter very often seek redress, or take legal proceedings. The surveyor
either himself settles the dispute between the owners, or
by his art gives
evidence to the judges for making their decision, that
one shall not encroach
on the mine of the other. Thus, first of all he measures the mines of each
party with a basket
rope and cords of linden bark; and having applied to the
cords an orbis
or a compass, he notes the directions in which they extend. Then he stretches the cords on the surveyor's field; and starting from that
point whose owners are in possession of the old meer toward the other,
whether it is in the hanging or footwall of the vein, he stretches a
cross
cord in a straight line, according to the sixth division of
the compass,
that is, at a right angle to the vein, for a distance of
three and a
half fathoms, and assigns to the older owners that which
belongs to
them. But if both ends of one vein are being dug out in two tunnels, or
drifts
from opposite directions, the surveyor first of all considers the lower
tunnel or drift and afterward the upper one, and judges how much each
of
them has risen little by little. On each side strong men take in their hands
a stretched cord and hold it
so that there is no point where it is not strained
tight; on each side
the surveyor supports the cord with a rod half a fathom
long, and stays
the rod at the end with a short stick as often as he thinks
it
necessary. But some fasten cords to the rods to make them steadier.
The surveyor attaches a suspended plummet level to the middle of the cord to
enable him to calculate more accurately on both sides, and from this he
ascer
tains whether one tunnel has risen more than another, or in
like manner one
drift more than another. Afterward he measures the incline of the shafts
on both sides, so that
he can estimate their position on each side. Then he
easily sees how many fathoms remain in the space which must be
broken
through. But the grade of each tunnel, as I said, should rise one fathom in
the
distance of one hundred fathoms.
The Swiss surveyors, when they wish to measure tunnels driven into
the
highest mountains, also use a rod half a fathom long, but composed of
three parts, which screw together, so that they may be shortened. They
use a cord made of linden bark to which are fastened slips of paper
showing
the number of fathoms. They also employ an instrument peculiar to them,
which has a needle; but
in place of the waxed circles they carry in their
hands a chart on
which they inscribe the readings of the instrument. The
instrument is placed on the back part of the rod so that the tongue,
and the
extended cord which runs through the three holes in the tongue,
demonstrates
the direction, and they note the number of fathoms. The tongue shows
whether the cord inclines forward or backward. The tongue does not hang,
a half-lying position. They measure the tunnels for the purpose of knowing
how many fathoms
they have been increased in elevation; how many fathoms
the lower is
distant from the upper one; how many fathoms of interval is
INDICATOR OF A SUSPENDED PLUMMET LEVEL.
the same vein,
or cross-stringers, or two veins which are approaching one
another.
But I return to our mines.
If the surveyor desires to fix the boundaries
of the meer within the
tunnels or drifts, and mark to them with a sign cut in the
rock, in the
same way that the
above ground, he first
of all ascertains, by measuring in the manner
which I have explained
above, which part of the tunnel or drift lies
beneath the surface
boundary mark, stretching the cords along the drifts to
a point beyond
that spot in the rock where he judges the mark should be
cut. Then, after the same cords have been laid out on the surveyor's field,
he starts from that upper cord at a point which shows the boundary
mark,
and stretches another cross-cord straight downward according to
the sixth
A—NEEDLE OF THE INSTRUMENT. B—ITS TONGUE. C, D, E—HOLES IN
THE TONGUE.
Then that part
of the lowest cord which lies beyond the part to which
the cross-cord
runs being removed, it shows at what point the boundary
mark should
be cut into the rock of the tunnel or drift. The cutting is made in the
presence of the two Jurors and the manager
and the foreman of each
mine. For as the
the boundary stones on the
surface, so the surveyor cuts in the rock a sign
which for this reason
is called the boundary rock. If he fixes the boundary
mark of a meer in which a shaft has recently
begun to be sunk on a vein,
first of all he measures and notes the
incline of that shaft by the com
pass or by another way with the
applied cords; then he measures all
the drifts up to that one in whose
rock the boundary mark has to
be cut. Of these drifts he measures each angle; then the cords, being
laid out
on the surveyor's field, in a similar way he stretches a
cross
cord, as I said, and cuts the sign on the rock. But if the underground
boundary rock has to be cut in a drift which lies
beneath the first drift, the
surveyor starts from the mark in the first
drift, notes the different angles,
one by one, takes his measurements,
and in the lower drift stretches a cord
beyond that place where he
judges the mark ought to be cut; and then,
as I said before, lays out
the cords on the surveyor's field. Even if a vein
runs differently in the lower drift from the upper one,
in which the first
boundary mark has been cut in the rock, still, in
the lower drift the mark
must be cut in the rock vertically beneath. For if he cuts the lower mark
obliquely from the upper one some part of
the possession of one mine is
taken away to its detriment, and given to
the other. Moreover, if it
happens that the underground boundary mark requires to
be cut in an
angle, the surveyor, starting from that angle, measures
one fathom toward
the front of the mine and another fathom toward the
back, and from these
measurements forms a triangle, and dividing its
middle by a cross-cord,
makes his cutting for the boundary mark.
Lastly, the surveyor sometimes, in order to make more certain, finds the
boundary of the meers in those places where many old boundary marks
are cut in the rock. Then, starting from a stake fixed on the surface,
he first of all
measures to the nearest mine; then he measures one shaft
after another;
then he fixes a stake on the surveyors' field, and making
a beginning
from it stretches the same cords in the same way and measures
them, and
again fixes in the ground a stake which for him will signify the end
of
his measuring. Afterward he again measures underground from that
spot at which he left
off, as many shafts and drifts as he can remember. Then
he returns to the surveyor's field, and starting again from the
second stake,
makes his measurements; and he does this as far as the
drift in which the
boundary mark must be cut in the rock. Finally, commencing from the
stake first fixed in the ground, he
stretches a cross-cord in a straight line to
the last stake, and this
shows the length of the lowest drift. The point
where they touch, he judges to be the place where the
underground boundary
mark should be cut.
END OF BOOK V.
Digging of veins I have written of, and the timbering
of shafts,
tunnels, drifts, and other excavations,
and the art of surveying. I will now speak first of
all, of the iron tools with which veins and
rocks are
broken, then of the buckets into which the lumps
of
earth, rock, metal, and other excavated materials
are thrown, in order
that they may be drawn, con
veyed, or carried out. Also, I will speak of the
water vessels and drains, then of the machines
of
different kinds,And while all these
matters are being described accurately, many methods
of work will be
explained.
There are certain iron tools which the miners designate by names of their
own, and besides these, there are wedges, iron blocks, iron plates,
hammers,
crowbars, pikes, picks, hoes, and shovels. Of those which are especially
referred to as “iron tools”
there are four varieties, which are different
from one another in
length or thickness, but not in shape, for the
upper end of all of them
is broad and square, so that it can be struck by the The lower end is pointed so as to split the hard rocks and veins
with
its point. All of these have eyes except the fourth.
The first,
which is in daily use among miners, is three-quarters of a
foot long, a digit
and a half wide, and a digit thick. The second is of the same width as the
first, and the same thickness,
but one and one half feet long, and is used to
shatter the hardest
veins in such a way that they crack open. The third
is the same length as the second, but is a little wider and
thicker; with
this one they dig the bottoms of those shafts which
slowly accumulate water. The fourth is nearly three palms and one digit long, two digits thick, and in
the upper end it is three digits wide, in the middle it is one palm
wide, and
at the lower end it is pointed like the others; with this
they cut out the
harder veins. The eye in the first tool is one palm distant from the upper
end, in the
second and third it is seven digits distant; each swells out
around the
eye on both sides, and into it they fit a wooden handle, which
they
hold with one hand, while they strike the iron tool with a hammer, after
placing it against the rock. These tools are made larger or smaller as
necessary. The smiths, as far as possible, sharpen again all that become dull.
A—FIRST “IRON TOOL.” B—SECOND. C—THIRD.
D—FOURTH.
BLOCK. G—IRON PLATE. H—WOODEN HANDLE.
I—HANDLE INSERTED IN FIRST TOOL.
A wedge is usually three palms and two digits long and six digits wide;
at the upper end, for a distance of a palm, it is three digits thick,
and
beyond that point it becomes thinner by degrees, until finally it
is quite
sharp.
The iron block is six digits in length and width; at the upper end it is
two digits thick, and at the bottom a digit and a half. The iron plate is
the same length and width as the iron block, but it is
very thin. All of these,
as I explained in the last book, are used when the hardest
kind of veins are
hewn out. Wedges, locks, and plates, are likewise made larger or smaller.
A—SMALLEST OF THE SMALLER HAMMERS. B—INTERMEDIATE.
C—LARGEST. D—SMALL
KIND OF THE LARGER HAMMER. E—LARGE
KIND. F—WOODEN HANDLE. G—HANDLE
FIXED IN THE SMALLEST
HAMMER.
Hammers are of two kinds, the smaller ones the miners hold in
one hand,
and the larger ones they hold with both hands. The former,
because of their size and use, are of three sorts. With the smallest,
that is to say, the lightest, they strike the second
“iron tool;” with the
intermediate one the first
“iron tool;” and with the largest the third “iron
tool”; this one is two digits wide and thick. Of the larger sort of hammers
there are two kinds; with the smaller they
strike the fourth “iron tool;”
with the larger they drive
the wedges into the cracks; the former are three,
and the latter five
digits wide and thick, and a foot long. All swell out in
their middle, in which there is an eye for a handle,
but in most cases the
handles are somewhat light, in order that the
workmen may be able to strike
more powerful blows by the hammer's full
weight being thus concentrated.
The iron crowbars are likewise of two kinds, and each kind is pointed at
one end. One is rounded, and with this they pierce to a shaft full of water
when
a tunnel reaches to it; the other is flat, and with this they knock out
of the stopes on to the floor, the rocks which have been softened by
the fire,
and which cannot be dislodged by the pike. A miner's pike, like a sailor's,
is a long rod having an iron head.
A—ROUND CROWBAR. B—FLAT CROWBAR. C—PIKE.
A—PICK. B—HOE. C—SHOVEL.
The miner's pick differs from a peasant's pick in that the latter is wide
at the bottom and sharp, but the former is pointed. It is used to dig out
ore which is not hard, such as earth. Likewise a hoe and shovel are in no
way different from the common
articles, with the one they scrape up earth
and sand, with the other
they throw it into vessels.
Now earth, rock, mineral substances and other things dug out with
the
pick or hewn out with the “iron tools” are hauled out of the
shaft
in buckets, or baskets, or hide buckets; they are drawn out of
tunnels in
wheelbarrows or open trucks, and from both they are
sometimes carried in
trays.
Buckets are of two kinds, which differ in size, but not in material or
shape. The smaller for the most part hold only about one
larger are generally
capable of carrying one-sixth of a
of unchangeable capacity, but they
often vary.
with hoops, one of which binds the top and the other the
bottom. The hoops are sometimes made of hazel and oak, but these are easily
broken by dashing against the shaft, while those made of iron are more
durable. In the larger buckets the staves are thicker and wider, as also are
both
hoops, and in order that the buckets may be more firm and strong,
they
have eight iron straps, somewhat broad, four of which run from the
upper hoop downwards, and four from the lower hoop upwards, as if to
meet
each other. The bottom of each bucket, both inside and outside, is furnished
with
two or three straps of iron, which run from one side of the lower hoop
to the other, but the straps which are on the outside are fixed
crosswise. Each bucket has two iron hafts which project above the edge, and it has an
iron semi-circular bail whose lower ends are fixed directly into the
hafts,
that the bucket may be handled more easily. Each kind of bucket is much
deeper than it is wide, and each is wider at
the top, in order that the material
which is dug out may be the more
easily poured in and poured out again. Into the smaller buckets strong boys, and into larger ones men, fill earth
from the bottom of the shaft with hoes; or the other material dug up is
shovelled into them or filled in with their hands, for which reason
these men
are called “shovellers.
into the bale; then the buckets are drawn up by machines—the
smaller ones,
because of their lighter weight, by machines turned by
men, and the larger
ones, being heavier, by the machines turned by
horses. Some, in place
of these buckets, substitute baskets which hold just as
much, or even more,
since they are lighter than the buckets; some use
sacks made of ox-hide
instead of buckets, and the drawing-rope hook is
fastened to their iron bale,
usually three of these filled with
excavated material are drawn up at the
same time as three are being
lowered and three are being filled by boys. The
latter are generally used at Schneeberg and the former at
Freiberg.
A—SMALL BUCKET. B—LARGE BUCKET. C—STAVES. D—IRON
HOOPS. E—IRON
STRAPS. F—IRON STRAPS ON THE BOTTOM.
G—HAFTS. H—IRON BALE. I—HOOK OF
DRAWING-ROPE.
K—BASKET. L—HIDE BUCKET OR SACK.
That which we call a
two, such as horses draw. When filled with excavated material it is pushed
It is made as follows: two planks
are chosen about five feet long, one
foot wide, and two digits thick; of
each of these the lower side is cut
away at the front for a length of one
foot, and at the back for a
length of two feet, while the middle is left whole. Then in the front parts are bored circular holes, in order that the ends of
an
axle may revolve in them. The intermediate parts of the planks are
perforated twice near the
bottom, so as to receive the heads of two little
cleats on which the
planks are fixed; and they are also perforated in the
middle, so as to
receive the heads of two end-boards, while keys fixed in
these
projecting heads strengthen the whole structure. The handles are
made out of the extreme ends of the long planks, and
they turn downward
at the ends that they may be grasped more firmly in
the hands. The small
wheel, of which there is only one, neither has a nave nor does
it revolve
around the axle, but turns around with it. From the felloe, which the
Greeks called
middle of the axle toward the opposite felloe; the axle is square,
with
the exception of the ends, each of which is rounded so as to turn
in the
opening. A workman draws out this barrow full of earth and rock and draws
it back
empty. Miners also have another wheelbarrow, larger than this
one, which they
use when they wash earth mixed with tin-stone on to which
a stream has
been turned. The front end-board of this one is deeper, in
order that the earth which
has been thrown into it may not fall out.
A—SMALL WHEELBARROW. B—LONG PLANKS THEREOF. C—END-BOARDS.
D—SMALL
WHEEL. E—LARGER BARROW. F—FRONT END-BOARD
THEREOF.
A—RECTANGULAR IRON BANDS ON TRUCK. B—ITS IRON STRAPS.
C—IRON AXLE.
D—WOODEN ROLLERS. E—SMALL IRON KEYS.
F—LARGE BLUNT IRON PIN.
G—SAME TRUCK UPSIDE DOWN.
The open truck has a capacity half as large again as a wheelbarrow; it is
about four feet long and about two and a half feet wide and deep; and
since
its shape is rectangular, it is bound together with three
rectangular iron
bands, and besides these there are iron straps on all
sides. Two small iron
axles are fixed to the bottom, around the ends of which
wooden rollers revolve
on either side; in order that the rollers shall
not fall off the immovable
axles, there are small iron keys. A large blunt pin fixed to the bottom of the
truck runs in a groove of a
plank in such a way that the truck does not
leave the beaten track. Holding the back part with his hands, the carrier
pushes out the truck
laden with excavated material, and pushes it back
again empty. Some people call it a “dog”
makes a noise which seems to
them not unlike the bark of a dog. This truck
is used when they draw loads out of the longest tunnels, both
because it is
moved more easily and because a heavier load can be
placed in it.
Bateas
are generally two feet long and one
foot wide. When they have been
filled with ore, especially when but little is dug
from the shafts and tunnels,
men either carry them out on their
shoulders, or bear them away hung from
A—SMALL BATEA. B—ROPE. C—LARGE BATEA.
their necks. Pliny
which was mined was carried out on men's
shoulders, but in truth this
method of carrying forth burdens is
onerous, since it causes great fatigue
to a great number of men, and
involves a large expenditure for labour; for
this reason it has been
rejected and abandoned in our day. The length of
the larger batea is as much as three feet, the width up to
a foot and a palm. In these bateas the metallic earth is washed for the purpose of testing
it.
Water-vessels differ both in the use to which they are put and in the
material of which they are made; some draw the water from the shafts
and
pour it into other things, as dippers; while some of the vessels
filled with
water are drawn out by machines, as buckets and bags; some
are made of
wood, as the dippers and buckets, and others of hides, as
the bags. The
water-buckets, just like the buckets which are filled with dry
material, are of
two kinds, the smaller and the larger, but these are
unlike the other buckets at
the top, as in this case they are narrower,
in order that the water may not be
spilled by being bumped against the
timbers when they are being drawn out
of the shafts, especially those
considerably inclined. The water is poured
into these buckets by dippers, which are small
wooden buckets, but unlike the
water-buckets, they are neither narrow
at the top nor bound with iron hoops,
but with hazel,—because
there is no necessity for either. The smaller buckets
are drawn up by machines turned by men, the larger
ones by those turned by
horses.
A—SMALLER WATER-BUCKET. B—LARGER WATER-BUCKET. C—DIPPER
A—WATER-BAG WHICH TAKES IN WATER BY ITSELF. B—WATER-BAG INTO
WHICH WATER
POURS WHEN IT IS PUSHED WITH A SHOVEL.
Our people give the name of water-bags to those very large skins for
carrying water which are made of two, or two and a half, ox-hides. When
these water-bags have undergone much wear and use, first the hair
comes
off them and they become bald and shining; after this they become
torn. If the tear is but a small one, a piece of smooth notched stick is put
into the broken part, and the broken bag is bound into its notches on
either
side and sewn together; but if it is a large one, they mend it
with a piece of
ox-hide. The water-bags are fixed to the hook of a drawing-chain and let
down and
dipped into the water, and as soon as they are filled they are drawn
up
by the largest machine. They are of two kinds; the one kind take in the
water by themselves; the
water pours into the other kind when it is pushed
in a certain way by a
wooden shovel.
When the water has been drawn out from the shafts, it is run off in
troughs, or into a hopper, through which it runs into the trough. Likewise
the water which flows along the sides of the tunnels is carried
off in drains. These are composed of two hollowed beams joined firmly together, so as to
hold the water which flows through them, and they are covered by planks
all along their course, from the mouth of the tunnel right up to the
extreme
end of it, to prevent earth or rock falling into them and
obstructing the flow
of the water. If much mud gradually settles in them the planks are raised
and the
drains are cleaned out, for they would otherwise become stopped up
and
obstructed by this accident. With regard to the trough lying above
A—TROUGH. B—HOPPER.
houses, these are
usually hollowed out of single trees. Hoppers are generally
made of four planks, so cut on the lower side and
joined together that the
top part of the hopper is broader and the
bottom part narrower.
I have sufficiently indicated the nature of the miners' iron tools and
their vessels. I will now explain their machines, which are of three kinds,
that is,
hauling machines, ventilating machines, and ladders. By means of
the hauling machines loads are drawn out of the shafts; the
ventilating
machines receive the air through their mouths and blow it
into shafts or
tunnels, for if this is not done, diggers cannot carry
on their labour without
great difficulty in breathing; by the steps of
the ladders the miners go
down into the shafts and come up again.
Hauling machines are of varied and diverse forms, some of them being
made with great skill, and if I am not mistaken, they were unknown to
the
Ancients. They have been invented in order that water may be drawn from
the depths
of the earth to which no tunnels reach, and also the excavated
material
from shafts which are likewise not connected with a tunnel, or if
so,
only with very long ones. Since shafts are not all of the same depth, there
is a great variety
among these hauling machines. Of those by which dry loads
are drawn out of the shafts, five sorts are
in the most common use, of which
I will now describe the first. Two timbers a little longer than the shaft are
placed beside it, the one
in the front of the shaft, the other at the back. Their extreme ends have holes through which stakes, pointed at the bottom
like wedges, are driven deeply into the ground, so that the timbers may
remain
stationary. Into these timbers are mortised the ends of two cross-timbers,
one laid
on the right end of the shaft, while the other is far enough
from the
left end that between it and that end there remains suitable
space for
placing the ladders. In the middle of the cross-timbers, posts are
fixed and secured with
iron keys. In hollows at the top of these posts
thick iron sockets hold the ends of
the barrel, of which each end projects
beyond the hollow of the post,
and is mortised into the end of another
piece of wood a foot and a half
long, a palm wide and three digits thick;
the other end of these pieces
of wood is seven digits wide, and into each
of them is fixed a round
handle, likewise a foot and a half long. A
winding-rope is wound around the barrel and fastened to it at the
middle part. The loop at each end of the rope has an iron hook which
is engaged in
the bale of a bucket, and so when the windlass revolves by
being turned
by the cranks, a loaded bucket is always being drawn out of the
shaft
and an empty one is being sent down into it. Two robust men turn
the windlass, each having a wheelbarrow near him,
into which he unloads
the bucket which is drawn up nearest to him; two
buckets generally fill a
wheelbarrow; therefore when four buckets have
been drawn up, each man
runs his own wheelbarrow out of the shed and
empties it. Thus it happens
that if shafts are dug deep, a hillock rises around the
shed of the windlass. If a vein is not metal-bearing, they pour out the earth and rock without
discriminating; whereas if it is metal-bearing, they preserve these
materials, When they draw up
buckets of water they empty the water through the
hopper into a trough,
through which it flows away.
A—TIMBER PLACED IN FRONT OF THE SHAFT. B—TIMBER PLACED AT THE
BACK OF THE
SHAFT. C—POINTED STAKES. D—CROSS-TIMBERS.
E—POSTS OR THICK PLANKS.
F—IRON SOCKETS. G—BARREL.
H—ENDS OF BARREL. I—PIECES OF WOOD.
K—HANDLE.
L—DRAWING-ROPE. M—ITS HOOK. N—BUCKET. O—BALE OF THE
BUCKET.
The next kind of machine, which miners employ when the shaft is
deeper,
differs from the first in that it possesses a wheel as well as cranks.
This windlass, if the load is not being drawn up from a great depth, is
turned
by one windlass man, the wheel taking the place of the other
man. But if the
depth is greater, then the windlass is turned by three men,
the wheel being
substituted for a fourth, because the barrel having
been once set in motion,
the rapid revolutions of the wheel help, and
it can be turned more easily. Sometimes masses of lead are hung on to this wheel, or are fastened to the
spokes, in order that when it is turned they depress the spokes by
their weight
and increase the motion; some persons for the same reason
fasten into the
barrel two, three, or four iron rods, and weight their
ends with lumps of lead. The windlass wheel differs from the wheel of a carriage and from the one
A—BARREL. B—STRAIGHT LEVERS. C—USUAL CRANK. D—SPOKES
OF WHEEL.
E—RIM OF THE SAME WHEEL.
which is turned by water
power, for it lacks the buckets of a water-wheel
and it lacks the nave
of a carriage wheel. In the place of the nave it has a thick
barrel, in which are mortised
the lower ends of the spokes, just as their upper
ends are mortised
into the rim. When three windlass men turn this machine,
four straight levers are
fixed to the one end of the barrel, and to the
other the crank which is
usual in mines, and which is composed of two limbs,
of which the
rounded horizontal one is grasped by the hands; the rect
angular
limb, which is at right angles to the horizontal one, has mortised in its
lower end the round handle, and in the upper end the end of the barrel. This
crank is worked by one man, the levers by two men, of whom one
pulls while
the other pushes; all windlass workers, whatsoever kind of
a machine they
may turn, are necessarily robust that they can sustain
such great toil.
The third kind of machine is less fatiguing for the workman, while it
raises larger loads; even though it is slower, like all other machines
which
have drums, yet it reaches greater depths, even to a depth of 180
feet. It
consists of an upright axle with iron journals at its extremities,
which
turn in two iron sockets, the lower of which is fixed in a block
set in the
ground and the upper one in the roof beam. This axle has at its lower end a
A—UPRIGHT AXLE. B—BLOCK. C—ROOF BEAM. D—WHEEL.
E—TOOTHED-DRUM.
F—HORIZONTAL AXLE. G—DRUM COMPOSED OF
RUNDLES. H—DRAWING ROPE.
I—POLE. K—UPRIGHT POSTS.
L—CLEATS ON THE WHEEL.
wheel made of thick planks joined firmly
together, and at its upper end a
toothed drum; this toothed drum turns
another drum made of rundles, which
is on a horizontal axle. A winding-rope is wound around this latter axle,
which turns in iron
bearings set in the beams. So that they may not fall, the
two workmen grasp with their hands a pole
fixed to two upright posts, and
then pushing the cleats of the lower
wheel backward with their feet, they
revolve the machine; as often as
they have drawn up and emptied one
bucket full of excavated material,
they turn the machine in the opposite
direction and draw out
another.
The fourth machine raises burdens once and a half as large again as the
two machines first explained. When it is made, sixteen beams are erected
each forty feet long, one
foot thick and one foot wide, joined at the top with
clamps and widely
separated at the bottom. The lower ends of all of
them are mortised into separate sills laid flat
upon the ground; these sills
are five feet long, a foot and a half
wide, and a foot thick. Each beam is also
connected with its sill by a post, whose upper end is
mortised into the beam
foot thick, and one foot
wide. Thus a circular area is made, the diameter of
which is fifty feet; in
the middle of this area a hole is sunk to a depth of ten
feet, and
rammed down tight, and in order to give it sufficient firmness, it is
strengthened with contiguous small timbers, through which pins are
driven,
for by them the earth around the hole is held so that it cannot
fall in. In
the bottom of the hole is planted a sill, three or four feet long and
a foot and a
half thick and wide; in order that it may remain fixed, it
is set into the small
timbers; in the middle of it is a steel socket in
which the pivot of the axle turns. In like manner a timber is mortised into two of the large beams, at the top
beneath the clamps; this has an iron bearing in which the other iron
journal of
the axle revolves. Every axle used in mining, to speak of them once for all,
has two iron
journals, rounded off on all sides, one fixed with keys in the centre
of each end. That part of this journal which is fixed to the end
of the axle is as
broad as the end itself and a digit thick; that which
projects beyond
the axle is round and a palm thick, or thicker if necessity
requires;
the ends of each miner's axle are encircled and bound by an
iron band
to hold the journal more securely. The axle of this machine,
except at the ends, is square, and is forty
feet long, a foot and a half thick
and wide. Mortised and clamped into the axle above the lower end are the
ends of
four inclined beams; their outer ends support two double
cross
beams similarly mortised into them; the inclined beams are
eighteen feet
long, three palms thick, and five wide. The two cross-beams are fixed to
the axle and held together by wooden
keys so that they will not separate,
and they are twenty-four feet
long. Next, there is a drum which is made of
three wheels, of which the middle
one is seven feet distant from the upper
one and from the lower one;
the wheels have four spokes which are
supported by the same number of
inclined braces, the lower ends of which
are joined together round the
axle by a clamp; one end of each spoke is
mortised into the axle and
the other into the rim. There are rundles all
round the wheels, reaching from the rim of the
lowest one to the rim of the
middle one, and likewise from the rim of
the middle wheel to the rim of the top
one; around these rundles are
wound the drawing-ropes, one between the lowest
wheel and the middle
one, the other between the middle and top wheels. The whole of this construction is shaped like a cone, and is covered with a
shingle roof, with the exception of that square part which faces the
shaft. Then cross-beams, mortised at both ends, connect a double row of upright
posts; all of these are eighteen feet long, but the posts are one foot
thick
and one foot wide, and the cross-beams are three palms thick and
wide. There are sixteen posts and eight cross-beams, and upon these cross-beams
are laid two timbers a foot wide and three palms thick, hollowed out to
a
width of half a foot and to a depth of five digits; the one is laid
upon the
upper cross-beams and the other upon the lower; each is long
enough to
reach nearly from the drum of the whim to the shaft. Near the same drum
each timber has a small round wooden roller six
digits thick, whose ends are
A—UPRIGHT BEAMS. B—SILLS LAID FLAT UPON THE GROUND.
C—POSTS. D—AREA.
E—SILL SET AT THE BOTTOM OF THE
HOLE. F—AXLE. G—DOUBLE CROSS-BEAMS.
H—DRUM.
I—WINDING-ROPES. K—BUCKET. L—SMALL PIECES OF WOOD HANGING
FROM DOUBLE CROSS-BEAMS. M—SHORT WOODEN BLOCK. N—CHAIN.
O—POLE BAR.
P—GRAPPLING HOOK. (Some members mentioned in
the text are not shown).Each timber also has a
wooden pulley, which together with its iron axle
revolves in holes in the
timber. These pulleys are hollowed out all round, in order that the
drawing
rope may not slip out of them, and thus each rope is drawn
tight and turns
over its own roller and its own pulley. The iron hook of each rope is engaged
with the bale of the bucket. Further, with regard to the double cross
beams which are mortised to
the lower part of the main axle, to each end
of them there is mortised
a small piece of wood four feet long. These appear
to hang from the double cross-beams, and a short wooden
block is fixed to the
lower part of them, on which a driver sits. Each of these blocks has an iron
clavis which holds a chain, and that in
turn a pole-bar. In this way it is
possible for two horses to draw this whim, now this
way and now that; turn
by turn one bucket is drawn out of the shaft
full and another is let down
into it empty; if, indeed, the shaft is
very deep four horses turn the whim. When a bucket has been drawn up, whether filled with dry or wet materials,
it must be emptied, and a workman inserts a grappling hook and
overturns
it; this hook hangs on a chain made of three or four links,
fixed to a timber.
The fifth machine is partly like the whim, and partly like the third rag
and chain pump, which draws water by balls when turned by horse power,
as I will explain a little later. Like this pump, it is turned by horse
power and has two axles, namely,
an upright one—about whose lower end,
which decends into an
underground chamber, there is a toothed drum—and a
horizontal
one, around which there is a drum made of rundles. It has indeed
two drums around its horizontal axle, similar to those of
the big machine, but
smaller, because it draws buckets from a shaft
almost two hundred and forty
feet deep. One drum is made of hubs to which cleats are fixed, and
the other is
made of rundles; and near the latter is a wheel two
feet deep, measured
on all sides around the axle, and one foot wide; and
against this
impinges a brake,
that it be stopped. This is necessary when the hide buckets are emptied
after being drawn up
full of rock fragments or earth, or as often as water
is poured out of
buckets similarly drawn up; for this machine not only
raises dry loads,
but also wet ones, just like the other four machines which
I have
already described. By this also, timbers fastened on to its winding
chain are let down
into a shaft. The brake is made of a piece of wood one
foot thick and half a foot
long, projecting from a timber that is suspended
by a chain from one
end of a beam which oscillates on an iron pin, this in
turn being
supported in the claws of an upright post; and from the other end
of
this oscillating beam a long timber is suspended by a chain, and from this
long timber again a short beam is suspended. A workman sits on the short
beam when the machine needs to be stopped,
and lowers it; he then inserts
a plank or small stick so that the two
timbers are held down and cannot be
raised. In this way the brake is raised, and seizing the drum, presses it
so
tightly that sparks often fly from it; the suspended timber to which
the short beam is attached, has several holes in which the chain is
A—TOOTHED DRUM WHICH IS ON THE UPRIGHT AXLE. B—HORIZONTAL AXLE.
C—DRUM
WHICH IS MADE OF RUNDLES. D—WHEEL NEAR IT.
E—DRUM MADE OF HUBS.
F—BRAKE. G—OSCILLATING BEAM.
H—SHORT BEAM. I—HOOK.Above this wheel
there are boards to prevent the water from dripping
down and wetting it, for
if it becomes wet the brake will not grip the
machine so well. Near the
other drum is a pin from which hangs a chain, in the last link
of which there
is an iron hook three feet long; a ring is fixed to the
bottom of the bucket,
and this hook, being inserted into it, holds the
bucket back so that the water
may be poured out or the fragments of
rock emptied.
The miners either carry, draw, or roll down the mountains the ore which
is hauled out of the shafts by these five machines or taken out of the
tunnels. In the winter time our people place a box on a sledge and draw
it down
the low mountains with a horse; and in this season they
also fill sacks
made of hide and load them on dogs, or place two or
three of them on a
small sledge which is higher in the fore part and lower at
the back. Sitting on these sacks, not without risk of his life, the bold
driver
guides the sledge as it rushes down the mountain into the valleys with
a stick, which he carries in his hand; when it is rushing down too
quickly he arrests it with the stick, or with the same stick brings it
back to
the track when it is turning aside from its proper course. Some of the
A—SLEDGE WITH BOX PLACED ON IT. B—SLEDGE WITH SACKS PLACED ON IT.
C—STICK.
D—DOGS WITH PACK-SADDLES. E—PIG-SKIN SACKS
TIED TO A ROPE.
and drag them down from the highest mountains, which neither
horses,
mules nor asses can climb. Strong dogs, that are trained to bear pack
saddles, carry these sacks
when empty into the mountains. When they
are filled with ore, bound with thongs, and fastened to a
rope, a man,
winding the rope round his arm or breast, drags them down
through the
snow to a place where horses, mules, or asses bearing
pack-saddles can
climb. There the ore is removed from the pigskin sacks and put into other
sacks
made of double or triple twilled linen thread, and these placed on the
pack-saddles of the beasts are borne down to the works where the ores
are washed or smelted. If, indeed, the horses, mules, or asses are able
to climb the mountains,
linen sacks filled with ore are placed on their saddles,
and they carry
these down the narrow mountain paths, which are passable
neither by
wagons nor sledges, into the valleys lying below the steeper
portions
of the mountains. But on the declivity of cliffs which beasts cannot
climb, are placed
long open boxes made of planks, with transverse cleats to
hold them
together; into these boxes is thrown the ore which has been
brought in
wheelbarrows, and when it has run down to the level it is gathered
into
sacks, and the beasts either carry it away on their backs or drag it away
after it has been thrown into sledges or wagons. When the drivers bring
ore down steep mountain slopes they use
two-wheeled carts, and they drag
behind them on the ground the trunks
of two trees, for these by their weight
hold back the heavily-laden
carts, which contain ore in their boxes, and check
their descent, and
but for these the driver would often be obliged to
bind chains to the
wheels. When these men bring down ore from mountains
which do not have such
declivities, they use wagons whose beds are twice
as long as those of
the carts. The planks of these are so put together that,
when the ore is unloaded
by the drivers, they can be raised and taken apart,
for they are only
held together by bars. The drivers employed by the owners
of the ore bring down thirty or sixty
wagon-loads, and the master of the
works marks on a stick the number of
loads for each driver. But some
ore, especially tin, after being taken from the mines, is
divided into eight
parts, or into nine, if the owners of the mine give
“ninth parts” to the
owners of the tunnel. This is occasionally done by measuring with a bucket,
but more
frequently planks are put together on a spot where, with the
addition
of the level ground as a base, it forms a hollow box. Each owner
provides for removing, washing, and smelting that portion
which has fallen
to him. (Illustration p. 170).
Into the buckets, drawn by these five machines, the boys or men throw
the earth and broken rock with shovels, or they fill them with their
hands;
hence they get their name of shovellers. As I have said, the same
machines raise not only dry loads, but also wet
ones, or water; but before
I explain the varied and diverse kinds of
machines by which miners are wont
A—HORSES WITH PACK-SADDLES. B—LONG BOX PLACED ON THE SLOPE OF THE
CLIFF.
C—CLEATS THEREOF. D—WHEELBARROW. E—TWO-WHEELED
CART. F—TRUNKS OF
TREES. G—WAGON. H—ORE BEING
UNLOADED FROM THE WAGON. I—BARS.
K—MASTER OF THE WORKS
MARKING THE NUMBER OF CARTS ON A STICK. L—BOXES
INTO WHICH ARE
THROWN THE ORE WHICH HAS TO BE DIVIDED.
chains,
pipes, and heavy timbers, should be lowered into deep vertical shafts.
A windlass is erected whose barrel has on each end four straight levers; it
is fixed into upright beams and around it is wound a rope, one end of
which
is fastened to the barrel and the other to those heavy bodies
which are slowly
lowered down by workmen; and if these halt at any part
of the shaft they
are drawn up a little way. When these bodies are very heavy, then behind
this windlass another is
erected just like it, that their combined strength
may be equal to the
load, and that it may be lowered slowly. Sometimes for
the same reason, a pulley is fastened with cords to the
roof-beam, and the rope
descends and ascends over it.
A—WINDLASS. B—STRAIGHT LEVERS. C—UPRIGHT BEAMS.
D—ROPE. E—PULLEY.
F—TIMBERS TO BE LOWERED.
Water is either hoisted or pumped out of shafts.
It is hoisted up after
being poured into buckets or water-bags; the
water-bags are generally
brought up by a machine whose water-wheels
have double paddles, while the
buckets are brought up by the five
machines already described, although in
certain localities the fourth
machine also hauls up water-bags of moderate
size. Water is drawn up also by chains of dippers, or by suction pumps, or
either brought up in buckets or drawn up by chains of dippers or
suction
pumps, and when there is much water it is either drawn up in
hide bags or
by rag and chain pumps.
First of all, I will describe the machines which draw water by chains
of
dippers, of which there are three kinds. For the first, a frame is
made entirely of iron bars: it is two and a
half feet high, likewise two and
a half feet long, and in addition
one-sixth and one-quarter of a digit
long, one-fourth and
one-twenty-fourth of a foot wide. In it there are three
little horizontal iron axles, which revolve in
bearings or wide pillows of steel. and also four iron wheels, of which two are made with rundles and the same
number are toothed. Outside the frame, around the lowest axle, is a
wooden fly-wheel, so
that it can be more readily turned, and inside the frame
is a smaller
drum which is made of eight rundles, one-sixth and one
twenty
fourth of a foot long. Around the second axle, which does not project
beyond the frame, and is
therefore only two and a half feet and one-twelfth
and one-third part
of a digit long, there is on the one side, a smaller toothed
wheel,
which has forty-eight teeth, and on the other side a larger drum,
which
is surrounded by twelve rundles one-quarter of a foot long. Around the
third axle, which is one inch and one-third thick, is a
larger toothed wheel
projecting one foot from the axle in all
directions, which has seventy-two
teeth. The teeth of each wheel are fixed in with screws, whose threads are
screwed into threads in the wheel, so that those teeth which are broken
can be
replaced by others; both the teeth and rundles are steel. The upper axle
projects beyond the frame, and is so skilfully mortised
into the body of
another axle that it has the appearance of being one;
this axle proceeds
through a frame made of beams which stands around
the shaft, into an iron
fork set in a stout oak timber, and turns on a
roller made of pure steel. Around this axle is a drum of the kind possessed by those machines which
draw water by rag and chain; this drum has triple curved iron clamps,
to which the links of an iron chain hook themselves, so that a great
weight
cannot tear them away. These links are not whole like the links of other
chains, but each one
being curved in the upper part on each side catches the
one which comes
next, whereby it presents the appearance of a double chain. At the point where one catches the other, dippers made of iron or brass
plates
and holding half a
one hundred links there will be
the same number of dippers pouring out water. When the shafts are inclined, the mouths of the dippers project and are
covered
on the top that they may not spill out the water, but when the
shafts are
vertical the dippers do not require a cover. By fitting the end of the lowest
small axle into the crank, the man who
works the crank turns the axle, and at
the same time the drum whose
rundles turn the toothed wheel of the second
axle; by this wheel is
driven the one that is made of rundles, which
A—IRON FRAME. B—LOWEST AXLE. C—FLY-WHEEL. D—SMALLER
DRUM MADE OF
RUNDLES. E—SECOND AXLE. F—SMALLER TOOTHED
WHEEL G—LARGER DRUM MADE
OF RUNDLES. H—UPPER AXLE.
I—LARGER TOOTHED WHEEL. K—BEARINGS.
L—PILLOW.
M—FRAMEWORK. N—OAK TIMBER O—SUPPORT OF IRON BEARING
P—ROLLER Q—UPPER DRUM. R—CLAMPS. S—CHAIN.
T—LINKS. V—DIPPERS
X—CRANK. Y—LOWER DRUM OR
BALANCE WEIGHT.
which the clamps are fixed. In this way the chain, together with the empty
dippers, is slowly let
down, close to the footwall side of the vein, into the sump
to the
bottom of the balance drum, which turns on a little iron axle, both ends
of which are set in a thick iron bearing. The chain is rolled round the drum
and the dippers fill with water; the
chain being drawn up close to the hanging
wall side, carries the
dippers filled with water above the drum of the upper
axle. Thus there are always three of the dippers inverted and pouring
water
into a lip, from which it flows away into the drain of the tunnel. This
machine is less useful, because it cannot be constructed without
great expense,
and it carries off but little water and is somewhat
slow, as also are other
machines which possess a great number of
drums.
A—WHEEL WHICH IS TURNED BY TREADING. B—AXLE. C—DOUBLE
CHAIN. D—LINK
OF DOUBLE CHAIN. E—DIPPERS. F—SIMPLE
CLAMPS. G—CLAMP WITH TRIPLE CURVES.
The next machine of this kind, described in a few words by Vitruvius,
more rapidly brings up dippers,
holding a
much water is continually flowing. This machine has no iron frame nor
drums, but has around its axle a
wooden wheel which is turned by treading;
the axle, since it has no
drum, does not last very long. In other respects
this pump resembles the first kind, except that it
differs from it by having
a double chain. Clamps should be fixed to the axle of this machine, just as
to the drum
of the other one; some of these are made simple and others
with triple
curves, but each kind has four barbs.
The third machine, which far excels the two just described, is made
when
a running stream can be diverted to a mine; the impetus of the
stream
striking the paddles revolves a water-wheel in place of the wheel
turned by treading. With regard to the axle, it is like the second machine,
A—WHEEL WHOSE PADDLES ARE TURNED BY THE FORCE OF THE STREAM.
B—AXLE.
C—DRUM OF AXLE, TO WHICH CLAMPS ARE FIXED.
D—CHAIN. E—LINK. F—DIPPERS.
G—BALANCE
DRUM.
but the drum which is round the axle, the chain, and the balance
drum, are
like the first machine. It has much more capacious dippers than even the
second machine, but
since the dippers are frequently broken, miners rarely
use these
machines; for they prefer to lift out small quantities of water by
the
first five machines or to draw it up by suction pumps, or, if there is
water-bags.
Enough, then, of the first sort of pumps.
I will now explain the other,
that is the pump which draws, by means of
pistons, water which has been
raised by suction. Of these there are seven varieties, which though they
differ from one
another in structure, nevertheless confer the same benefits
upon
miners, though some to a greater degree than others. The first pump
is made as follows. Over the sump is placed a flooring, through which a
pipe—or two
lengths of pipe, one of which is joined into the other—are let
down to the bottom of the sump; they are fastened with pointed iron
clamps
driven in straight on both sides, so that the pipes may remain
fixed. The
lower end of the lower pipe is enclosed in a trunk two feet deep;
this trunk,
hollow like the pipe, stands at the bottom of the sump, but
the lower opening
of it is blocked with a round piece of wood; the
trunk has perforations
round about, through which water flows into it. If there is one length of
pipe, then in the upper part of the trunk
which has been hollowed out there is
enclosed a box of iron, copper, or
brass, one palm deep, but without a bottom,
and a rounded valve so
tightly closes it that the water, which has been drawn
up by suction,
cannot run back; but if there are two lengths of pipe, the
box is
enclosed in the lower pipe at the point of junction. An opening or a
spout in the upper pipe reaches to the drain of the
tunnel. Thus the work
man, eager at his labour, standing on the flooring
boards, pushes the piston
down into the pipe and draws it out again. At the top of the piston-rod is a
hand-bar and the bottom is fixed in a
shoe; this is the name given to the
leather covering, which is almost
cone-shaped, for it is so stitched that it is
tight at the lower end,
where it is fixed to the piston-rod which it surrounds,
but in the
upper end where it draws the water it is wide open. Or else an
iron disc one digit thick is used, or one of wood six digits
thick, each of which
is far superior to the shoe. The disc is fixed by an iron key which pene
trates through the
bottom of the piston-rod, or it is screwed on to the
rod; it is round,
with its upper part protected by a cover, and has five or
six openings,
either round or oval, which taken together present a star-like
appearance; the disc has the same diameter as the inside of the pipe,
so that it can be just drawn up and down in it. When the workman draws
the piston up, the water which has passed in at
the openings of the disc,
whose cover is then closed, is raised to the
hole or little spout, through which
it flows away; then the valve of
the box opens, and the water which has
passed into the trunk is drawn
up by the suction and rises into the pipe;
but when the workman pushes
down the piston, the valve closes and allows
the disc again to draw in
the water.
The piston of the second pump is more easily moved up and down.
When
this pump is made, two beams are placed over the sump, one near the
right side
of it, and the other near the left. To one beam a pipe is fixed with iron clamps;
to the other is fixed
either the forked branch of a tree or a timber cut out at
the top in
the shape of a fork, and through the prongs of the fork a round
hole is
bored. Through a wide round hole in the middle of a sweep passes
A—SUMP. B—PIPES. C—FLOORING. D—TRUNK.
E—PERFORATIONS OF TRUNK.
F—VALVE. G—SPOUT.
H—PISTON-ROD. I—HAND-BAR OF PISTON. K—SHOE. L—DISC
WITH ROUND OPENINGS. M—DISC WITH OVAL OPENINGS. N—COVER.
O—THIS MAN IS
BORING LOGS AND MAKING THEM INTO PIPES.
P—BORER WITH AUGER. Q—WIDER BORER.
A—ERECT TIMBER. B—AXLE. C—SWEEP WHICH TURNS ABOUT THE AXLE.
D—PISTON
ROD. E—CROSS-BAR. F—RING WITH WHICH TWO
PIPES ARE GENERALLY JOINED.
an iron axle, so fastened in the holes in
the fork that it remains fixed, and
the sweep turns on this axle. In one end of the sweep the upper end of a
piston-rod is fastened with
an iron key; at the other end a cross-bar is also
fixed, to the extreme
ends of which are handles to enable it to be held more
firmly in the
hands. And so when the workman pulls the cross-bar upward,
he forces the piston
into the pipe; when he pushes it down again he draws
the piston out of
the pipe; and thus the piston carries up the water which
has been drawn
in at the openings of the disc, and the water flows away through
the
spout into the drains. This pump, like the next one, is identical with
the first in all that
relates to the piston, disc, trunk, box, and valve.
The third pump is not unlike the one just described, but in place of
one
upright, posts are erected with holes at the top, and in these holes the
ends of an axle revolve. To the middle of this axle are fixed two wooden
bars, to the end of one
of which is fixed the piston, and to the end of the
other a heavy piece
of wood, but short, so that it can pass between the two
posts and may
move backward and forward. When the workman pushes
this piece of wood, the piston is drawn out of
the pipe; when it returns by its
A—POSTS. B—AXLE. C—WOODEN BARS. D—PISTON ROD.
E—SHORT PIECE OF WOOD.
F—DRAIN. G—THIS MAN IS
DIVERTING THE WATER WHICH IS FLOWING OUT OF THE DRAIN,
TO PREVENT IT
FROM FLOWING INTO THE TRENCHES WHICH ARE BEING DUG.
own weight, the
piston is pushed in. In this way, the water which the pipe
contains is drawn through the
openings in the disc and emptied by the piston
through the spout into
the drain. There are some who place a hand-bar
underneath in place of the short
piece of wood. This pump, as also the last
before described, is less generally used
among miners than the others.
The fourth kind is not a simple pump but a duplex one.
It is made as
follows. A rectangular block of beechwood, five feet long, two and a half
feet
wide, and one and a half feet thick, is cut in two and hollowed out wide
and deep enough so that an iron axle with cranks can revolve in it. The axle
is placed between the two halves of this box, and the first
part of the axle,
which is in contact with the wood, is round and the
straight end forms a
journal. Then the axle is bent down the depth of a foot and again bent so
as to
continue straight, and at this point a round piston-rod hangs from it;
next it is bent up as far as it was bent down; then it continues a
little way
straight again, and then it is bent up a foot and again
continues straight,
at which point a second round piston-rod is hung
from it; afterward it
A—BOX B—LOWER PART OF BOX. C—UPPER PART OF SAME.
D—CLAMPS. E—PIPES
BELOW THE BOX. F—COLUMN PIPE FIXED
ABOVE THE BOX. G—IRON AXLE. H—PISTON
RODS.
I—WASHERS TO PROTECT THE BEARINGS. K—LEATHERS. L—EYES IN
THE AXLE.
M—RODS WHOSE ENDS ARE WEIGHTED WITH LUMPS OF LEAD.
N—CRANK.
(
end of it, which also acts as a journal, is straight. This part which protrudes
through the wood is protected by two iron
washers in the shape of discs, to
which are fastened two leather
washers of the same shape and size, in order
to prevent the water which
is drawn into the box from gushing out. These
discs are around the axle; one of them is inside the box and the
other
outside. Beyond this, the end of the axle is square and has two eyes, in
which
are fixed two iron rods, and to their ends are weighted lumps of lead,
so that the axle may have a greater propensity to revolve; this axle
can
easily be turned when its end has been mortised in a crank. The upper part
of the box is the shallower one, and the lower part the
deeper, the upper
part is bored out once straight down through the
middle, the diameter of the
opening being the same as the outside
diameter of the column pipe; the
lower box has, side by side, two
apertures also bored straight down;
these are for two pipes, the space
of whose openings therefore is twice as
great as that of the upper
part; this lower part of the box is placed
upon the two pipes, which
are fitted into it at their upper ends, and the
lower ends of these
pipes penetrate into trunks which stand in the
sump. These trunks have perforations through which the water flows into
them. The iron axle is placed in the inside of the box, then the two iron
piston-rods which hang from it are let down through the two pipes to
the depth
of a foot. Each piston has a screw at its lower end which holds a thick iron
plate,
shaped like a disc and full of openings, covered with a leather, and
similarly to the other pump it has a round valve in a little box. Then the
upper part of the box is placed upon the lower one and properly
fitted to it on
every side, and where they join they are bound by wide
thick iron plates, and
held with small wide iron wedges, which are
driven in and are fastened with
clamps. The first length of column pipe is fixed into the upper part of the
box,
and another length of pipe extends it, and a third again extends this one,
and so on, another extending on another, until the uppermost one
reaches the
drain of the tunnel. When the crank worker turns the axle, the pistons in
turn draw the water
through their discs; since this is done quickly, and
since the area of
openings of the two pipes over which the box is set, is twice
as large
as the opening of the column pipe which rises from the box, and since
the pistons do not lift the water far up, the impetus of the water from
the
lower pipes forces it to rise and flow out of the column pipe into
the drain of
the tunnel. Since a wooden box frequently cracks open, it is better to
make it of
lead or copper or brass.
The fifth kind of pump is still less simple, for it is composed of two or
three pumps whose pistons are raised by a machine turned by men, for
each
piston-rod has a tappet which is raised, each in succession, by
two cams on
a barrel; two or four strong men turn it. When the pistons descend into
the pipes their discs draw the water; when
they are raised these force the
water out through the pipes. The upper part of each of these piston-rods,
which is half a foot
square, is held in a slot in a cross-beam; the lower part,
which drops
down into the pipes, is made of another piece of wood and is
round. Each of these three pumps is composed of two lengths of pipe fixed
A—TAPPETS OF PISTON-RODS. B—CAMS OF THE BARREL. C—SQUARE
UPPER PARTS
OF PISTON-RODS. D—LOWER ROUNDED PARTS OF PISTON-RODS.
E—CROSS-BEAMS.
F—PIPES. G—APERTURES OF PIPES.
H—TROUGH. (Fifth kind of pump—see p. 181).
A—WATER-WHEEL. B—AXLE. C—TRUNK ON WHICH THE LOWEST PIPE
STANDS.
D—BASKET SURROUNDING TRUNK. (Sixth kind of pump—see
p. 184.)
This machine draws the water higher, as much as
twenty-four feet. If the diameter of the pipes is large, only two pumps are
made; if
smaller, three, so that by either method the volume of water is the
same. This also must be understood regarding the other machines and
their
pipes. Since these pumps are composed of two lengths of pipe, the
little iron
box having the iron valve which I described before, is not enclosed
in
a trunk, but is in the lower length of pipe, at that point where it joins
the upper one; thus the rounded part of the piston-rod is only as long
as
the upper length of pipe; but I will presently explain this more
clearly.
The sixth kind of pump would be just the same as the fifth were it not
that it has an axle instead of a barrel, turned not by men but by a
water
wheel, which is revolved by the force of water striking its
buckets. Since water-power far exceeds human strength, this machine draws water
through its pipes by discs out of a shaft more than one hundred feet
deep. The bottom of the lowest pipe, set in the sump, not only of this pump but
also of the others, is generally enclosed in a basket made of
wicker-work, to
prevent wood shavings and other things being sucked in.
(See p. 183.)
The seventh kind of pump, invented ten years ago, which is the most
ingenious, durable, and useful of all, can be made without much
expense. It
is composed of several pumps, which do not, like those last
described, go down
into the shaft together, but of which one is below
the other, for if there are
three, as is generally the case, the lower
one lifts the water of the sump and
pours it out into the first tank;
the second pump lifts again from that tank
into a second tank, and the
third pump lifts it into the drain of the tunnel. A wheel fifteen feet high raises the piston-rods of all these pumps at the
same
time and causes them to drop together. The wheel is made to revolve by
paddles, turned by the force of a stream
which has been diverted to the
mountain. The spokes of the water-wheel are mortised in an axle six feet
long and
one foot thick, each end of which is surrounded by an iron band,
but in
one end there is fixed an iron journal; to the other end is attached an
iron like this journal in its posterior part, which is a digit thick
and as wide
as the end of the axle itself. Then the iron extends horizontally, being
rounded and about three digits
in diameter, for the length of a foot, and
serves as a journal; thence,
it bends to a height of a foot in a curve,
like the horn of the moon,
after which it again extends straight out for
one foot; thus it comes
about that this last straight portion, as it
revolves in an orbit
becomes alternately a foot higher and a foot lower than
the first
straight part. From this round iron crank there hangs the first flat
pump-rod, for the
crank is fixed in a perforation in the upper end of this flat
pump-rod
just as the iron key of the first set of “claws” is fixed into
the
lower end. In order to prevent the pump-rod from slipping off it, as it
could
easily do, and that it may be taken off when necessary, its opening
is
wider than the corresponding part of the crank, and it is fastened on
both sides by iron keys. To prevent friction, the ends of the pump-rods are
protected by iron
plates or intervening leathers. This first pump-rod is
about twelve feet long, the other two are
twenty-six feet, and each is a palm
A—SHAFT. B—BOTTOM PUMP. C—FIRST TANK. D—SECOND PUMP.
E—SECOND TANK.
F—THIRD PUMP. G—TROUGH. H—THE
IRON SET IN THE AXLE. I—FIRST PUMP ROD.
K—SECOND PUMP ROD.
L—THIRD PUMP ROD. M—FIRST PISTON ROD. N—SECOND
PISTON
ROD. O—THIRD PISTON ROD. P—LITTLE AXLES.
Q—“CLAWS.”The sides of each pump-rod are covered and
protected by iron plates,
which are held on by iron screws, so that a part
which has received
damage can be repaired. In the “claws” is set a
small round axle, a foot and a half
long and two palms thick. The ends are
encircled by iron bands to prevent the iron journals which
revolve in the
iron bearings of the wood from slipping out of it.
the
wooden “claws” extend two feet, with a width and thickness of
six
digits; they are three palms distant from each other, and both the
inner and
outer sides are covered with iron plates. Two rounded iron keys two digits
thick are immovably fixed into the
claws. The one of these keys per
forates the lower end of the first
pump-rod, and the upper end of the second
pump-rod which is held fast. The other key, which is likewise immovable,
perforates the iron end of
the first piston-rod, which is bent in a curve and
is immovable. Each such piston-rod is thirteen feet long and three digits
thick, and
descends into the first pipe of each pump to such depth that its
disc
nearly reaches the valve-box. When it descends into the pipe, the
water, penetrating through the
openings of the disc, raises the leather, and
when the piston-rod is
raised the water presses down the leather, and this
supports its
weight; then the valve closes the box as a door closes an
entrance. The pipes are joined by two iron bands, one palm wide, one
outside the
other, but the inner one is sharp all round that it may
fit into each
pipe and hold them together. Although at the present time
pipes lack the inner band, still they have
nipples by which they are joined
together, for the lower end of the
upper one holds the upper end of the lower
one, each being hewn away
for a length of seven digits, the former inside, the
latter outside, so
that the one can fit into the other. When the piston-rod
descends into the first pipe, that valve which I
have described is closed;
when the piston-rod is raised, the valve is
opened so that the water can run
in through the perforations. Each one of such pumps is composed of two
lengths of pipe, each of which
is twelve feet long, and the inside diameter is
seven digits. The lower one is placed in the sump of the shaft, or in a tank,
and its
lower end is blocked by a round piece of wood, above which there are
six perforations around the pipe through which the water flows into it. The
upper part of the upper pipe has a notch one foot deep and a palm
wide,
through which the water flows away into a tank or trough. Each tank is
two feet long and one foot wide and deep. There is the same number of
axles, “claws,” and rods of each
kind as there are pumps; if there are three
pumps, there are only two
tanks, because-the sump of the shaft and the drain
of the tunnel take
the place of two. The following is the way this machine
draws water from a shaft. The wheel being turned raises the first pump
rod, and the pump-rod
raises the first “claw,” and thus also the second
pump-rod,
and the first piston-rod; then the second pump-rod raises the
second
“claw,” and thus the third pump-rod and the second piston-rod;
then the third pump-rod raises the third “claw” and the
third piston-rod,
no use in the last pump. In turn, when the first pump-rod descends, each
set of
“claws” is lowered, each pump-rod and each piston-rod. And by this
system, at the same time the water is lifted into the tanks
and drained out of
them; from the sump at the bottom of the shaft it is
drained out, and it
is poured into the trough of the tunnel. Further, around the main axle there
may be placed two water wheels, if
the river supplies enough water to turn
them, and from the back part of
each round iron crank, one or two pump-rods
can be hung, each of which
can move the piston-rods of three pumps. Lastly, it is necessary that the shafts from which the water is pumped out in
pipes should be vertical, for as in the case of the hauling machines,
all pumps
which have pipes do not draw the water so high if the pipes
are inclined in
inclined shafts, as if they are placed vertically in
vertical shafts.
If the river does not supply enough water-power to turn the
last
described pump, which happens because of the nature of the
locality
or occurs during the summer season when there are daily
droughts, a
machine is built with a wheel so low and light that the
water of ever so little a
A—WATER WHEEL OF UPPER MACHINE. B—ITS PUMP. C—ITS TROUGH.
D—WHEEL OF
LOWER MACHINE. E—ITS PUMP. F—RACE.This water, falling into a race, runs therefrom on to a
second high and
heavy wheel of a lower machine, whose pump lifts the water
out of a
deep shaft. Since, however, the water of so small a stream cannot
alone revolve the
lower water-wheel, the axle of the latter is turned at the start
with a
crank worked by two men, but as soon as it has poured out into a pool
the water which has been drawn up by the pumps, the upper wheel draws
up this water by its own pump, and pours it into the race, from which
it
flows on to the lower water-wheel and strikes its buckets. So both this
water from the mine, as well as the water of the stream,
being turned down
the races on to that subterranean wheel of the lower
machine, turns it, and
water is pumped out of the deeper part of the
shaft by means of two or
three pumps.
If the stream supplies enough water straightway to turn a higher and
heavier water-wheel, then a toothed drum is fixed to the other end of
the
axle, and this turns the drum made of rundles on another axle set
below it. To each end of this lower axle there is fitted a crank of round iron curved
like the horns of the moon, of the kind employed in machines of this
description. This machine, since it has rows of pumps on each side,
draws great
quantities of water.
Of the rag and chain pumps there are six kinds known to us, of which
the
first is made as follows: A cave is dug under the surface of earth or in a
tunnel, and timbered on all sides by stout posts and planks, to prevent
either
the men from being crushed or the machine from being broken by
its collapse. In this cave, thus timbered, is placed a water-wheel fitted to an angular
axle.
The iron journals of the axle revolve in iron pillows, which are held in
timbers
of sufficient strength. The wheel is generally twenty-four feet high,
occasionally thirty, and
in no way different from those which are made for
grinding corn, except
that it is a little narrower. The axle has on one side
a drum with a groove in the middle of its
circumference, to which are fixed
many four-curved iron clamps. In these clamps catch the links of the chain,
which is drawn through the
pipes out of the sump, and which again falls,
through a timbered
opening, right down to the bottom into the sump to a
balancing drum. There is an iron band around the small axle of the
balancing drum, each
journal of which revolves in an iron bearing fixed to a
timber. The chain turning about this drum brings up the water by the
balls
through the pipes. Each length of pipe is encircled and protected by
five iron bands, a
palm wide and a digit thick, placed at equal distances from
each other;
the first band on the pipe is shared in common with the
preceding
length of pipe into which it is fitted, the last band with the
succeed
ing length of pipe which is fitted into it. Each length of pipe, except the
first, is bevelled on the outer
circumference of the upper end to a distance
of seven digits and for a
depth of three digits, in order that it may be inserted
into the length
of pipe which goes before it; each, except the last, is reamed
out on
the inside of the lower end to a like distance, but to the depth
A—UPPER AXLE. B—WHEEL WHOSE BUCKETS THE FORCE OF THE STREAM
STRIKES.
C—TOOTHED DRUM. D—SECOND AXLE. E—DRUM
COMPOSED OF RUNDLES. F—CURVED
ROUND IRONS. G—ROWS OF
PUMPS.
follows. And each length of pipe is fixed with iron clamps to the timbers of
the
shaft, that it may remain stationary. Through this continuous series
of pipes, the water is drawn by the balls
of the chain up out of the sump as
far as the tunnel, where it flows
out into the drains through an aperture in
the highest pipe. The balls which lift the water are connected by the iron
links of the
chain, and are six feet distant from one another; they are made
of the
hair of a horse's tail sewn into a covering to prevent it from being
pulled out by the iron clamps on the drum; the balls are of such size
that
one can be held in each hand. If this machine is set up on the surface of
the earth, the stream which
turns the water-wheel is led away through open
air ditches; if in a
tunnel, the water is led away through the subterranean
drains. The buckets of the water-wheel, when struck by the impact of the
stream,
move forward and turn the wheel, together with the drum, whereby
the
chain is wound up and the balls expel the water through the pipes. If
the wheel of this machine is twenty-four feet in diameter, it draws
water from a
shaft two hundred and ten feet deep; if thirty feet in
diameter, it will draw
water from a shaft two hundred and forty feet
deep. But such work requires
a stream with greater water-power.
The next pump has two drums, two rows of pipes and two
drawing
chains whose balls lift out the water; otherwise they are
like the last pump. This pump is usually built when an excessive amount of water flows into the
sump. These two pumps are turned by water-power; indeed, water draws
water.
The following is the way of indicating the increase or decrease of the
water in an underground sump, whether it is pumped by this rag and
chain
pump or by the first pump, or the third, or some other. From a beam which
is as high above the shaft as the sump is deep, is
hung a cord, to one
end of which there is fastened a stone, the other
end being attached to a
plank. The plank is lowered down by an iron wire fastened to the
other end;
when the stone is at the mouth of the shaft the plank
is right down the
shaft in the sump, in which water it floats. This
plank is so heavy that it can drag down the wire and its iron clasp
and
hook, together with the cord, and thus pull the stone upwards. Thus, as
the water decreases, the plank decends and the stone is raised;
on the
contrary, when the water increases the plank rises and the stone
is lowered. When the stone nearly touches the beam, since this indicates that the water
has been exhausted from the sump by the pump, the overseer in charge of
the
machine closes the water-race and stops the water-wheel: when the
stone
nearly touches the ground at the side of the shaft, this
indicates that the
sump is full of water which has again collected in
it, because the water raises
the plank and thus the stone drags back
both the rope and the iron wire;
then the overseer opens the
water-race, whereupon the water of the stream
again strikes the buckets
of the water-wheel and turns the pump. As
workmen generally cease from their labours on the yearly holidays,
and
A—WHEEL. B—AXLE. C—JOURNALS. D—PILLOWS. E—DRUM.
F—CLAMPS.
G—DRAWING-CHAIN. H—TIMBERS. I—BALLS.
K—PIPE. L—RACE OF STREAM.
the pump, if
necessary, must continue to draw water all the time, a bell rings
aloud
continuously, indicating that this pump, or any other kind, is uninjured
and nothing is preventing its turning. The bell is hung by a cord from
a small wooden axle held in the timbers
which stand over the shaft, and
a second long cord whose upper end is
fastened to the small axle is lowered
into the shaft; to the lower end
of this cord is fastened a piece of wood;
and as often as a cam on the
main axle strikes it, so often does the bell ring
and give forth a
sound.
The third pump of this kind is employed by miners when no river capable
of turning a water-wheel can be diverted, and it is made as follows. They
first dig a chamber and erect strong timbers and planks to prevent
the sides
from falling in, which would overwhelm the pump and kill the
men. The
roof of the chamber is protected with contiguous timbers, so
arranged that
the horses which pull the machine can travel over it. Next they again set up
sixteen beams forty feet long and one foot wide
and thick, joined by clamps
at the top and spreading apart at the
bottom, and they fit the lower end
of each beam into a separate sill
laid flat on the ground, and join these by a
post; thus there is
created a circular area of which the diameter is fifty
feet. Through an opening in the centre of this area there descends an
upright
square axle, forty-five feet long and a foot and a half wide and thick;
its lower pivot revolves in a socket in a block laid flat on the ground
in the
chamber, and the upper pivot revolves in a bearing in a beam
which is mor
tised into two beams at the summit beneath the clamps;
the lower pivot is
seventeen feet distant from either side of the
chamber,
rear. At the height of a foot above its lower end, the axle has a toothed wheel,
the diameter of which is twenty-two feet. This wheel is composed of four
spokes and eight rim pieces; the spokes
are fifteen feet long and three
quarters of a foot wide and
thick
the other in the two rims where they are joined
together. These rims are three
quarters of a foot thick and one foot wide, and
from them there rise and
project upright teeth three-quarters of a foot
high, half a foot wide, and six
digits thick. These teeth turn a second horizontal axle by means of a drum
composed of
twelve rundles, each three feet long and six digits wide and
thick. This drum, being turned, causes the axle to revolve, and around this
axle there is a drum having iron clamps with four-fold curves in which
catch
the links of a chain, which draws water through pipes by means of
balls. The iron journals of this horizontal axle revolve on pillows which are set in
the centre of timbers. Above the roof of the chamber there are mortised
into the upright axle
the ends of two beams which rise obliquely; the upper
ends of these
beams support double cross-beams, likewise mortised to the
axle. In the outer end of each cross-beam there is mortised a small wooden
piece which appears to hang down; in this wooden piece there is
similarly
A—UPRIGHT AXLE. B—TOOTHED WHEEL. C—TEETH.
D—HORIZONTAL AXLE.
E—DRUM WHICH IS MADE OF RUNDLES.
F—SECOND DRUM. G—DRAWING-CHAIN.
H—THE BALLS.
a chain, and this chain again a pole-bar. This machine, which draws water
from a shaft two hundred and forty feet
deep, is worked by thirty-two horses;
eight of them work for four
hours, and then these rest for twelve hours, and
the same number take
their place. This kind of machine is employed at the
foot of the HarzFurther, if
necessity arises, several pumps of this kind are often built
for the purpose of
mining one vein, but arranged differently in
different localities varying
according to the depth. At Schemnitz, in the Carpathian mountains, there
are three pumps, of
which the lowest lifts water from the lowest sump to
the first drains,
through which it flows into the second sump; the intermediate
one lifts
from the second sump to the second drain, from which it flows into
the
third sump; and the upper one lifts it to the drains of the tunnel, through
which it flows away. This system of three machines of this kind is turned
by ninety-six
horses; these horses go down to the machines by an inclined
A—AXLE. B—DRUM. C—DRAWING-CHAIN. D—BALLS.
E—CLAMPS.
The
lowest of these machines is set in a deep place, which is distant
from the
surface of the ground 660 feet.
The fourth species of pump belongs to the same genera, and is made
as
follows. Two timbers are erected, and in openings in them, the ends of a
barrel
revolve. Two or four strong men turn the barrel, that is to say, one
or two pull
the cranks, and one or two push them, and in this way help the
others;
alternately another two or four men take their place. The barrel
of this machine, just like the horizontal axle of the other
machines, has a
drum whose iron clamps catch the links of a
drawing-chain. Thus water
is drawn through the pipes by the balls from a depth of
forty-eight feet. Human strength cannot draw water higher than this, because such very
heavy labour exhausts not only men, but even horses; only water-power
can drive continuously a drum of this kind. Several pumps of this kind, as
of the last, are often built for the
purpose of mining on a single vein,
but they are arranged differently
for different positions and depths.
A—AXLES. B—LEVERS. C—TOOTHED DRUM. D—DRUM MADE OF
RUNDLES.
E—DRUM IN WHICH IRON CLAMPS ARE FIXED.
The fifth pump of this kind is partly like the third and partly like the
fourth, because it is turned by strong men like the last, and like the
third
it has two axles and three drums, though each axle is horizontal. The
journals of each axle are so fitted in the pillows of the beams that
they cannot
fly out; the lower axle has a crank at one end and a
toothed drum at the
other end; the upper axle has at one end a drum
made of rundles, and at
the other end, a drum to which are fixed iron
clamps, in which the links of a
chain catch in the same way as before,
and from the same depth, draw water
through pipes by means of balls. This revolving machine is turned by two
pairs of men alternately, for
one pair stands working while the other sits
taking a rest; while they
are engaged upon the task of turning, one pulls
the crank and the other
pushes, and the drums help to make the pump turn
more easily.
The sixth pump of this kind likewise has two axles.
At one end of the
lower axle is a wheel which is turned by two men
treading, this is twenty
three feet high and four feet wide, so
that one man may stand alongside
the other. At the other end of this axle is a toothed wheel.
The upper
axle has two drums
and one wheel; the first drum is made of rundles, and to
the other
there are fixed the iron clamps. The wheel is like the one on the
second machine which is chiefly used
for drawing earth and broken rock
out of shafts. The treaders, to prevent themselves from falling, grasp in
their hands
poles which are fixed to the inner sides of the wheel. When
they turn this wheel, the toothed drum being made to revolve, sets
in motion
the other drum which is made of rundles, by which means again
the links
of the chain catch to the cleats of the third drum and draw
water through
pipes by means of balls,—from a depth of sixty-six
feet.
But the largest machine of all those which draw water is the one which
follows. First of all a reservoir is made in a timbered chamber; this
reser
voir is eighteen feet long and twelve feet wide and high. Into this reservoir
a stream is diverted through a water-race or through
the tunnel; it has two
entrances and the same number of gates. Levers are fixed to the upper part
of these gates, by which they can be
raised and let down again, so that by one
way the gates are opened and
in the other way closed. Beneath the openings
are two plank troughs which carry the water flowing
from the reservoir, and
pour it on to the buckets of the water-wheel,
the impact of which turns the
wheel. The shorter trough carries the water, which strikes the buckets
that
turn the wheel toward the reservoir, and the longer trough carries
the
water which strikes those buckets that turn the wheel in the opposite
direction. The casing or covering of the wheel is made of joined boards to
which
strips are affixed on the inner side. The wheel itself is thirty-six feet
in diameter, and is mortised to an
axle, and it has, as I have already said,
two rows of buckets, of which
one is set the opposite way to the other, so
that the wheel may be
turned toward the reservoir or in the opposite
A—AXLES. B—WHEEL WHICH IS TURNED BY TREADING. C—TOOTHED
WHEEL.
D—DRUM MADE OF RUNDLES. E—DRUM TO WHICH ARE FIXED
IRON CLAMPS.
F—SECOND WHEEL. G—BALLS.The axle is square and is thirty-five feet long and two feet thick
and
wide. Beyond the wheel, at a distance of six feet, the axle has four hubs,
one
foot wide and thick, each one of which is four feet distant from the
next
to these hubs are fixed by iron nails as many pieces of wood
as are necessary
to cover the hubs, and, in order that the wood pieces
may fit tight, they are
broader on the outside and narrower on the
inside; in this way a drum is
made, around which is wound a chain to
whose ends are hooked leather bags. The reason why a drum of this kind is made, is that the axle may be kept in
good condition, because this drum when it becomes worn away by use can
be repaired easily. Further along the axle, not far from the end, is another
drum one foot
broad, projecting two feet on all sides around the axle. And
to this, when occasion demands, a brake is applied forcibly and
holds back
the machine; this kind of brake I have explained before. Near the axle,
in place of a hopper, there is a floor with a
considerable slope, having in
front of the shaft a width of fifteen
feet and the same at the back; at each
side of it there is a stout post
carrying an iron chain which has a large hook. Five men operate this machine; one lets down the doors which close the
reservoir gates, or by drawing down the levers, opens the water-races;
this
man, who is the director of this machine, stands in a hanging cage
beside the
reservoir. When one bag has been drawn out nearly as far as the sloping
floor, he
closes the water gate in order that the wheel may be stopped; when
the
bag has been emptied he opens the other water gate, in order that the
other set of buckets may receive the water and drive the wheel in the
opposite
direction. If he cannot close the water-gate quickly enough, and the water
continues to flow, he calls out to his comrade and bids him raise the
brake
upon the drum and stop the wheel. Two men alternately empty the bags,
one standing on that part of the
floor which is in front of the shaft,
and the other on that part which
is at the back. When the bag has been
nearly drawn up—of which fact a certain link
of the chain gives warning—the
man who stands on the one part of
the floor, catches a large iron hook in one
link of the chain, and
pulls out all the subsequent part of the chain toward
the floor, where
the bag is emptied by the other man. The object of this
hook is to prevent the chain, by its own weight, from
pulling down the
other empty bag, and thus pulling the whole chain from
its axle and
dropping it down the shaft. His comrade in the work, seeing that the bag
filled with water has been
nearly drawn out, calls to the director of the
machine and bids him
close the water of the tower so that there will be time
to empty the
bag; this being emptied, the director of the machine first of
all
slightly opens the other water-gate of the tower to allow the end of the
chain, together with the empty bag, to be started into the shaft again,
and
then opens entirely the water-gates. When that part of the chain which
has been pulled on to the floor has
been wound up again, and has been let
down over the shaft from the
drum, he takes out the large hook which was
fastened into a link of the
chain. The fifth man stands in a sort of cross-cut
beside the sump, that he may
not be hurt, if it should happen that a link
A—RESERVOIR. B—RACE. C, D—LEVERS. E, F—TROUGHS UNDER
THE WATER GATES.
G, H—DOUBLE ROWS OF BUCKETS. I—AXLE.
K—LARGER DRUM. L—DRAWING-CHAIN.
M—BAG.
N—HANGING CAGE. O—MAN WHO DIRECTS THE MACHINE. P, Q—MEN
EMPTYING BAGS.
the bag with a wooden shovel,
and fills it with water if it fails to take
in the water spontaneously. In these days, they sew an iron band into the
top of each bag that it
may constantly remain open, and when lowered into
the sump may fill
itself with water, and there is no need for a man to act as
governor of
the bags. Further, in these days, of those men who stand on
the floor the one
empties the bags, and the other closes the gates of the
reservoir and
opens them again, and the same man usually fixes the large
hook in the
link of the chain. In this way, three men only are employed in
working this machine; or
even—since sometimes the one who empties the
bag presses the
brake which is raised against the other drum and thus stops
the
wheel—two men take upon themselves the whole labour.
But enough of haulage machines; I will now speak of ventilating
machines. If a shaft is very deep and no tunnel reaches to it, or no drift
from
another shaft connects with it, or when a tunnel is of great length and
no shaft reaches to it, then the air does not replenish itself. In such a case it
weighs heavily on the miners, causing them to breathe
with difficulty, and
sometimes they are even suffocated, and burning
lamps are also extinguished. There is, therefore, a necessity for machines which the Greeks call
sound—which enable the miners to breathe
easily and carry on their work.
These devices are of three genera.
The first receives and diverts into
the shaft the blowing of the wind,
and this genus is divided into three species,
of which the first is as
follows. Over the shaft—to which no tunnel connects—
are placed three
sills a little longer than the shaft, the first over the front,
the
second over the middle, and the third over the back of the shaft. Their
ends have openings, through which pegs, sharpened at the bottom,
are driven
deeply into the ground so as to hold them immovable, in the
same way that
the sills of the windlass are fixed. Each of these sills is mortised into each
of three cross-beams, of which
one is at the right side of the shaft, the second
at the left, and the
third in the middle. To the second sill and the second
cross-beam—each of which is
placed over the middle of the shaft—planks
are fixed which are
joined in such a manner that the one which precedes
always fits into
the groove of the one which follows. In this way four angles
and the same number of intervening hollows are
created, which collect the
winds that blow from all directions. The planks are roofed above with a
cover made in a circular shape, and
are open below, in order that the wind may
not be diverted upward and
escape, but may be carried downward; and there
by the winds of
necessity blow into the shafts through these four openings. However, there is no need to roof this kind of machine in those localities in
which it can be so placed that the wind can blow down through its
topmost
part.
A—SILLS. B—POINTED STAKES. C—CROSS-BEAMS. D—UPRIGHT
PLANKS.
E—HOLLOWS. F—WINDS. G—COVERING DISC.
H—SHAFTS. I—MACHINE
WITHOUT A COVERING.
The second machine of this genus turns the blowing wind into a shaft
through a long box-shaped conduit, which is made of as many lengths of
planks, joined together, as the depth of the shaft requires; the joints
are
smeared with fat, glutinous clay moistened with water. The mouth of this con
duit either projects out of the shaft to a
height of three or four feet, or it does
not project; if it projects,
it is shaped like a rectangular funnel, broader and
wider at the top
than the conduit itself, that it may the more easily gather
the wind;
if it does not project, it is not broader than the conduit, but
planks
are fixed to it away from the direction in which the wind is blowing,
which catch the wind and force it into the conduit.
The third of this genus of machine is made of a pipe or pipes and
a
barrel. Above the uppermost pipe there is erected a wooden barrel, four
A—PROJECTING MOUTH OF CONDUIT. B—PLANKS FIXED TO THE MOUTH OF THE
CONDUIT
WHICH DOES NOT PROJECT.
feet high and three feet in
diameter, bound with wooden hoops; it has a
square blow-hole always
open, which catches the breezes and guides them
down either by a pipe
into a conduit or by many pipes into the shaft. To
the top of the upper pipe is attached a circular table as thick as
the bottom of the barrel, but of a little less diameter, so that the
barrel may be
turned around on it; the pipe projects out of the table
and is fixed in a
round opening in the centre of the bottom of the
barrel. To the end of the
pipe a perpendicular axle is fixed which runs through
the centre of the barrel
into a hole in the cover, in which it is
fastened, in the same way as at the
bottom. Around this fixed axle and the table on the pipe, the movable
barrel is
easily turned by a zephyr, or much more by a wind, which govern
the
wing on it. This wing is made of thin boards and fixed to the upper
part of the
barrel on the side furthest away from the blow-hole; this, as I
have
said, is square and always open. The wind, from whatever quarter of
which way
the barrel turns the blow-hole towards the wind itself; the
blow-hole
receives the wind, and it is guided down into the shaft by means
of the
conduit or pipes.
A—WOODEN BARRELS. B—HOOPS. C—BLOW-HOLES. D—PIPE.
E—TABLE. F—AXLE. G—OPENING IN THE BOTTOM OF THE
BARREL.
H—WING.
The second genus of blowing machine is made with fans, and is likewise
varied and of many forms, for the fans are either fitted to a windlass
barrel
or to an axle. If to an axle, they are either contained in a hollow drum,
which is made
of two wheels and a number of boards joining them together,
or else in
a box-shaped casing. The drum is stationary and closed on the
sides, except for round holes
of such size that the axle may turn in them;
it has two square
blow-holes, of which the upper one receives the air, while
the lower
one empties into the conduit through which the air is led down the
shaft. The ends of the axle, which project on each side of the drum, are
supported by forked posts or hollowed beams plated with thick iron; one
end of the axle has a crank, while in the other end are fixed four rods
with
thick heavy ends, so that they weight the axle, and when turned,
make it
A—DRUM. B—BOX-SHAPED CASING. C—BLOW-HOLE. D—SECOND
HOLE.
E—CONDUIT. F—AXLE. G—LEVER OF AXLE.
H—RODS.And so, when the workman turns the axle
by the crank, the fans, the
description of which I will give a little later, draw
in the air by the
blow-hole, and force it through the other blow-hole which
leads to the
conduit, and through this conduit the air penetrates into the
shaft.
The one with the box-shaped casing is furnished with just the same
things as the drum, but the drum is far superior to the box: for the
fans so
fill the drum that they almost touch it on every side, and
drive into the
conduit all the air that has been accumulated; but they
cannot thus fill
the box-shaped casing, on account of its angles, into
which the air partly
retreats; therefore it cannot be as useful as the
drum. The kind with a
box-shaped casing is not only placed on the ground, but
is also set up on timbers
like a windmill, and its axle, in place of a
crank, has four sails outside,
like the sails of a windmill. When these are struck by the wind they turn
the axle, and in this way
its fans—which are placed within the casing—drive
A—BOX-SHAPED CASING PLACED ON THE GROUND. B—ITS BLOW-HOLE.
C—ITS AXLE
WITH FANS. D—CRANK OF THE AXLE. E—RODS OF
SAME. F—CASING SET ON TIMBERS.
G—SAILS WHICH THE AXLE HAS
OUTSIDE THE CASING.Although
this machine has no need of men whom it is necessary to pay to
work the
crank, still when the sky is devoid of wind, as it often is,
the machine does
not turn, and it is therefore less suitable than the
others for ventilating a shaft.
In the kind where the fans are fixed to an axle, there is generally a
hollow stationary drum at one end of the axle, and on the other end is
fixed
a drum made of rundles. This rundle drum is turned by the toothed wheel
of a lower axle, which
is itself turned by a wheel whose buckets receive the
impetus of water. If the locality supplies an abundance of water this
machine is most
useful, because to turn the crank does not need men
who require pay,
and because it forces air without cessation through the
conduit into
the shaft.
A—HOLLOW DRUM. B—ITS BLOW-HOLE. C—AXLE WITH FANS.
D—DRUM
WHICH IS MADE OF RUNDLES. E—LOWER AXLE. F—ITS
TOOTHED WHEEL.
G—WATER WHEEL.
Of the fans which are fixed on to an axle contained in a drum or box,
there are three sorts. The first sort is made of thin boards of such length
and width as the
height and width of the drum or box require; the second
long thin blades of poplar or some other flexible wood; the third sort
has
boards like the last, to which are bound double and triple rows of
goose
feathers. This last is less used than the second, which in turn is less used
than
the first. The boards of the fan are mortised into the quadrangular
parts of the
barrel axle.
A—FIRST KIND OF FAN. B—SECOND KIND OF FAN. C—THIRD KIND OF
FAN. D—QUADRANGULAR PART OF AXLE. E—ROUND PART OF SAME.
F—CRANK.
Blowing machines of the third genus, which are no less varied and of no
fewer forms than those of the second genus, are made with bellows, for
by its
blasts the shafts and tunnels are not only furnished with air
through conduits
or pipes, but they can also be cleared by suction of
their heavy and pestilential
vapours. In the latter case, when the bellows is opened it draws the
vapours from
the conduits through its blow-hole and sucks these vapours
into itself;
in the former case, when it is compressed, it drives the air through
its nozzle into the conduits or pipes. They are compressed either by a man,
fixed
to the timbers above the conduit which projects out of the shaft, and so
placed that when the blast is blown through the conduit, its nozzle is
set in the conduit. When it is desired to suck out heavy or pestilential
vapours, the
blow-hole of the bellows is fitted all round the mouth of the
conduit. Fixed to the upper bellows board is a lever which couples
with another
running downward from a little axle, into which it is
mortised so that
it may remain immovable; the iron journals of this little
axle revolve
in openings of upright posts; and so when the workman pulls
down the
lever the upper board of the bellows is raised, and at the same time
the flap of the blow-hole is dragged open by the force of the wind. If the
nozzle of the bellows is enclosed in the conduit it draws pure
air into itself,
but if its blow-hole is fitted all round the mouth of
the conduit it exhausts
the heavy and pestilential vapours out of the
conduit and thus from the
shaft, even if it is one hundred and twenty
feet deep. A stone placed on the
upper board of the bellows depresses it and then
the flap of the blow-hole is
A—SMALLER PART OF SHAFT. B—SQUARE CONDUIT. C—BELLOWS.
D—LARGER PART
OF SHAFT.The bellows, by the first method, blows fresh air into the conduit
through its nozzle, and by the second method blows out through the
nozzle
the heavy and pestilential vapours which have been collected. In this
latter case fresh air enters through the larger part of the
shaft, and the miners
getting the benefit of it can sustain their toil. A certain smaller part of the
shaft which forms a kind of estuary,
requires to be partitioned off from the
other larger part by
uninterrupted lagging, which reaches from the top of the
shaft to the
bottom; through this part the long but narrow conduit reaches
down
nearly to the bottom of the shaft.
When no shaft has been sunk to such depth as to meet a tunnel driven
far
into a mountain, these machines should be built in such a manner that
the workman can move them about. Close by the drains of the tunnel
through which the water flows away,
wooden pipes should be placed and
joined tightly together in such a
manner that they can hold the air; these
should reach from the mouth of
the tunnel to its furthest end. At the mouth
of the tunnel the bellows should be so placed that through
its nozzle it can
blow its accumulated blasts into the pipes or the
conduit; since one blast
A—TUNNEL. B—PIPE. C—NOZZLE OF DOUBLE BELLOWS.
the air, whereby the miners are enabled to continue
their work.
If heavy vapours need to be drawn off from the tunnels, generally three
double or triple bellows, without nozzles and closed in the forepart,
are placed
upon benches. A workman compresses them by treading with his feet, just
as persons
compress those bellows of the organs which give out varied and
sweet
sounds in churches. These heavy vapours are thus drawn along the
air-pipes and through the
blow-hole of the lower bellows board, and are
expelled through the
blow-hole of the upper bellows board into the open
air, or into some
shaft or drift. This blow-hole has a flap-valve, which the
noxious blast opens, as often
as it passes out. Since one volume of air con
stantly rushes in to take the place of
another which has been drawn out by
the bellows, not only is the heavy
air drawn out of a tunnel as great as 1,200
feet long, or even longer,
but also the wholesome air is naturally drawn in
through that part of
the tunnel which is open outside the conduits. In this way
the air is changed, and the miners are enabled to carry on
the work they have
begun. If machines of this kind had not been invented, it would be necessary
for miners to drive two tunnels into a mountain, and continually, at
every
two hundred feet at most, to sink a shaft from the upper tunnel
to the
lower one, that the air passing into the one, and descending by
the shafts
into the other, would be kept fresh for the miners; this
could not be done
without great expense.
There are two different machines for operating, by means of horses, the
above described bellows. The first of these machines has on its axle a
wooden wheel, the rim of
which is covered all the way round by steps; a
horse is kept
continually within bars, like those within which horses are held
to be
shod with iron, and by treading these steps with its feet it turns the
wheel,
together with the axle; the cams on the axle press down the
sweeps which
compress the bellows. The way the instrument is made which raises the
bellows again, and also
the benches on which the bellows rest, I will explain
more clearly in
Book IX. Each bellows, if it draws heavy vapours
out of a tunnel, blows them out
of the hole in the upper board; if they are
drawn out of a shaft, it
blows them out through its nozzle. The wheel has
a round hole, which is transfixed with a pole when the
machine needs to be
stopped.
The second machine has two axles; the upright one is turned by a horse,
and its toothed drum turns a drum made of rundles on a horizontal axle;
in other respects this machine is like the last. Here, also, the nozzles of
the bellows placed in the conduits blow a
blast into the shaft or tunnel.
In the same way that this last machine can refresh the heavy air of a
shaft or tunnel, so also could the old system of ventilating by the
constant
shaking of linen cloths, which Pliny
A—MACHINE FIRST DESCRIBED. B—THIS WORKMAN, TREADING WITH HIS
FEET, IS COM
PRESSING THE BELLOWS. C—BELLOWS WITHOUT NOZZLES.
D—HOLE BY WHICH HEAVY
VAPOURS OR BLASTS ARE BLOWN OUT.
E—CONDUITS. F—TUNNEL. G—SECOND
MACHINE DESCRIBED.
H—WOODEN WHEEL. I—ITS STEPS. K—BARS. L—HOLE IN
SAME WHEEL. M—POLE. N—THIRD MACHINE DESCRIBED.
O—UPRIGHT AXLE.
P—ITS TOOTHED DRUM. Q—HORIZONTAL
AXLE. R—ITS DRUM WHICH IS MADE OF RUNDLES.
A—TUNNEL. B—LINEN CLOTH.
heavier with the depth of a shaft,
of which fact he has made mention, but
also with the length of a
tunnel.
The climbing machines of miners are ladders, fixed to one side of the shaft,
and these reach either to the tunnel or to the bottom of the shaft. I need not
describe how they are made, because they are used everywhere,
and need
not so much skill in their construction as care in fixing
them. However,
miners go down into mines not only by the steps of ladders, but
they are
also lowered into them while sitting on a stick or a wicker
basket, fastened to
the rope of one of the three drawing machines which
I described at first. Further, when the shafts are much inclined, miners and other workmen
sit
in the dirt which surrounds their loins and slide down in the same way
that boys do in winter-time when the water on some hillside has
congealed
with the cold, and to prevent themselves from falling, one
arm is wound about
a rope, the upper end of which is fastened to a beam
at the mouth of the shaft,
and the lower end to a stake fixed in the
bottom of the shaft. In these three
ways miners descend into the shafts. A fourth way may be mentioned
which is employed when men and horses go
down to the underground
A—DESCENDING INTO THE SHAFT BY LADDERS. B—BY SITTING ON A STICK.
C—BY
SITTING ON THE DIRT. D—DESCENDING BY STEPS CUT IN THE
ROCK.
a screw and have steps cut in the rock,
as I have already described.
It remains for me to speak of the ailments and accidents of miners, and of
the methods by which they can guard against these, for we should always
devote more care to maintaining our health, that we may freely perform
our
bodily functions, than to making profits. Of the illnesses, some affect the
joints, others attack the lungs, some
the eyes, and finally some are fatal to
men.
Where water in shafts is abundant and very cold, it frequently injures
the limbs, for cold is harmful to the sinews. To meet this, miners should
make themselves sufficiently high boots of
rawhide, which protect their
legs from the cold water; the man who does
not follow this advice will
suffer much ill-health, especially when he
reaches old age. On the other
hand, some mines are so dry that they are entirely devoid
of water, and this
dryness causes the workmen even greater harm, for
the dust which is stirred
and beaten up by digging penetrates into the
windpipe and lungs, and
produces difficulty in breathing, and the
disease which the Greeks call
implants consumption in the body; hence in the mines of the Carpathian
Mountains women are found who have married seven husbands, all of whom
this terrible consumption has carried off to a premature death. At Altenberg
in Meissen there is found in the mines black
and ulcers to the bone; this also corrodes iron, for which reason the
keys
of their sheds are made of wood. Further, there is a certain kind of
which
eats away the feet of the workmen when they have become wet, and
similarly their hands, and injures their lungs and eyes. Therefore, for their
long enough to reach
to the elbow, and they should fasten loose veils over their
faces; the
dust will then neither be drawn through these into their wind
pipes
and lungs, nor will it fly into their eyes. Not dissimilarly, among the
Romans
dust.
Stagnant air, both that which remains in a shaft and that which remains
in a tunnel, produces a difficulty in breathing; the remedies for this
evil
are the ventilating machines which I have explained above. There is another
illness even more destructive, which soon brings death
to men who work
in those shafts or levels or tunnels in which the hard
rock is broken by fire. Here the air is infected with poison, since large and small veins and seams
in the rocks exhale some subtle poison from the minerals, which is
driven
out by the fire, and this poison itself is raised with the smoke
not unlike
ore is smelted. If this poison cannot escape from the ground, but falls down
into the
pools and floats on their surface, it often causes danger, for if at any
time the water is disturbed through a stone or anything else, these
fumes rise
again from the pools and thus overcome the men, by being
drawn in with their
breath; this is even much worse if the fumes of the
fire have not yet all
escaped. The bodies of living creatures who are infected with this poison
generally swell immediately and lose all movement and feeling, and they
die
without pain; men even in the act of climbing from the shafts by
the
steps of ladders fall back into the shafts when the poison
overtakes them,
because their hands do not perform their office, and
seem to them to be round
and spherical, and likewise their feet. If by good fortune the injured
ones escape these evils, for a little
while they are pale and look like
dead men. At such times, no one should descend into the mine or into the
neighbouring mines, or if he is in them he should come out quickly. Prudent
and skilled miners burn the piles of wood on Friday, towards
evening, and
and in the meantime the
poisonous fumes pass away.
There are also times when a reckoning has to be made with Orcus,
for some metalliferous
localities, though such are rare, spontaneously
produce poison and
exhale pestilential vapour, as is also the case with some
openings in
the ore, though these more often contain the noxious fumes. In the towns of the plains of Bohemia there are some caverns which,
at
certain seasons of the year, emit pungent vapours which put out lights
and kill the miners if they linger too long in them. Pliny, too, has left
a record that when wells are sunk, the sulphurous
or aluminous vapours
which arise kill the well-diggers, and it is a
test of this danger if a burning
lamp which has been let down is
extinguished. In such cases a second well
is dug to the right or left, as an
air-shaft, which draws off these noxious
vapours. On the plains they construct bellows which draw up these noxious
vapours
and remedy this evil; these I have described before.
Further, sometimes workmen slipping from the ladders into the shafts
break their arms, legs, or necks, or fall into the sumps and are
drowned;
often, indeed, the negligence of the foreman is to blame, for
it is his special
work both to fix the ladders so firmly to the timbers
that they cannot break
away, and to cover so securely with planks the
sumps at the bottom of the
shafts, that the planks cannot be moved nor
the men fall into the water;
wherefore the foreman must carefully
execute his own work. Moreover,
he must not set the entrance of the shaft-house toward the
north wind,
lest in winter the ladders freeze with cold, for when this
happens the men's
hands become stiff and slippery with cold, and cannot
perform their office
of holding. The men, too, must be careful that, even if none of these things
happen,
they do not fall through their own carelessness.
Mountains, too, slide down and men are crushed in their fall and perish.
In fact, when in olden days Rammelsberg, in Goslar, sank down, so many
men were crushed in the ruins that in one day, the records tell us,
about
400 women were robbed of their husbands. And eleven years ago, part
of the mountain of Altenberg, which had been
excavated, became loose and
sank, and suddenly crushed six miners; it
also swallowed up a hut and one
mother and her little boy. But this generally occurs in those mountains
which contain Therefore, miners should leave numerous
arches under the mountains
which need support, or provide underpinning. Falling pieces of rock also injure their limbs, and to prevent this from
hap
pening, miners should protect the shafts, tunnels, and
drifts.
The venomous ant which exists in Sardinia is not found in our mines.
This animal is, as Solinus
is called
who imprudently sit on it. But, as the same writer tells us, springs of warm
and salubrious waters
gush out in certain places, which neutralise the venom
inserted by the
ants.
In some of our mines, however, though in very few, there are other
pernicious pests. These are demons of ferocious aspect, about which I have
spoken in my
book Demons of this kind
are expelled and put to flight by prayer and
fasting.
Some of these evils, as well as certain other things, are the reason why
pits are occasionally abandoned. But the first and principal cause is that
they do not yield metal, or
if, for some fathoms, they do bear metal they
become barren in depth. The second cause is the quantity of water which
flows in; sometimes the
miners can neither divert this water into the
tunnels, since tunnels
cannot be driven so far into the mountains, or they
cannot draw it out
with machines because the shafts are too deep; or if they
could draw it
out with machines, they do not use them, the reason
undoubtedly being
that the expenditure is greater than the profits of a
moderately poor
vein. The third cause is the noxious air, which the owners
sometimes cannot
overcome either by skill or expenditure, for which reason
the digging
is sometimes abandoned, not only of shafts, but also of tunnels. The
fourth cause is the poison produced in particular places, if it is
not in our
power either completely to remove it or to moderate its
effects. This is the
reason why the caverns in the Plain known as LaurentiusThe fifth cause are the
fierce and murderous demons, for if they cannot
be expelled, no one escapes
from them. The sixth cause is that the underpinnings become loosened
and collapse,
and a fall of the mountain usually follows; the underpinnings
are then
only restored when the vein is very rich in metal. The seventh
cause is military operations. Shafts and tunnels should not be re-opened
unless we are quite certain
of the reasons why the miners have deserted them,
because we ought not
to believe that our ancestors were so indolent and
spiritless as to
desert mines which could have been carried on with profit. Indeed, in our own days, not a few miners, persuaded by old women's tales,
have re-opened deserted shafts and lost their time and trouble. Therefore,
to prevent future generations from being led to act in such a
way, it is
advisable to set down in writing the reason why the digging
of each shaft or
tunnel has been abandoned, just as it is agreed was
once done at Freiberg,
when the shafts were deserted on account of the
great inrush of water.
END OF BOOK VI.
Since the Sixth Book has described the iron tools,
the vessels and the
machines used in mines, this
Book will describe the methods of
assaying
because it
is desirable to first test them in order
that the material mined may be
advantageously
smelted, or that the dross may be purged away and
the metal made pure. Although writers have men
tioned such tests, yet none of them have
set down the
directions for performing them, wherefore it is no
wonder that those who come later have written nothing on the subject.
By tests of this kind miners can determine with certainty whether
ores
contain any metal in them or not; or if it has already been
indicated
that the ore contains one or more metals, the tests show whether
it is
much or little; the miners also ascertain by such tests the method by
which the metal can be separated from that part of the ore devoid of
it;
and further, by these tests, they determine that part in which
there is much
metal from that part in which there is little. Unless these tests have been
carefully applied before the metals are
melted out, the ore cannot be smelted
without great loss to the owners,
for the parts which do not easily melt in the
fire carry the metals off
with them or consume them. In the last case, they pass
off with the fumes; in the other case they
are mixed with the slag and furnace
accretions, and in such event the
owners lose the labour which they have spent
in preparing the furnaces
and the crucibles, and further, it is necessary for them
to incur fresh
expenditure for fluxes and other things. Metals, when they have
been melted out, are usually assayed in order
that we may ascertain what pro
portion of silver is in a
gold is in one
or lead is contained in a
contained in one And from this we can calculate whether it
will be worth while to
separate the precious metals from the base metals, or
not. Further, a test of this kind shows whether coins are good or are
debased; and readily detects silver, if the coiners have mixed more
than is
lawful with the gold; or copper, if the coiners have alloyed
with the gold or
silver more of it than is allowable. I will explain all these methods with the
utmost care that I can.
The method of assaying ore used by mining people, differs from
smelting
only by the small amount of material used. Inasmuch as, by
smelting a small quantity, they learn whether the
smelting of a large
particular to employ assays,
they may, as I have already said, sometimes smelt
the metal from the
ore with a loss or sometimes without any profit; for they
expense. Both processes, however, are carried out in the same way, for just
as we
assay ore in a little furnace, so do we smelt it in the large furnace. Also
in both cases charcoal and not wood is burned. Moreover, in the crucible
when metals are tested, be they gold, silver,
copper, or lead, they are mixed in
precisely the same way as they are
mixed in the blast furnace when they
are smelted. Further, those who assay ores with fire, either pour out the
metal in a
liquid state, or, when it has cooled, break the crucible and clean
flows from the furnace into the forehearth, pours in
cold water and takes the
slag from the metal with a hooked bar. Finally, in the same way that gold
and silver are separated from lead in
a cupel, so also are they separated in
the cupellation furnace.
It is necessary that the assayer who is testing ore or metals should be
prepared and instructed in all things necessary in assaying, and that
he
should close the doors of the room in which the assay furnace
stands, lest
ROUND ASSAY FURNACE.
RECTANGULAR ASSAY FURNACE.
they are intent on the work. It is also necessary for him to place his balances
in a case, so that
when he weighs the little buttons of metal the scales may
not be
agitated by a draught of air, for that is a hindrance to his work.
Now I will describe the different things which are necessary in assaying,
beginning with the assay furnace, of which one differs from another in
shape, material, and the place in which it is set. In shape, they may be
round or rectangular, the latter shape being more
suited to assaying ores. The materials of the assay furnaces differ, in that one is made of bricks,
another of iron, and certain ones of clay. The one of bricks is built on a
chimney-hearth which is three and a half
feet high; the iron one is placed
in the same position, and also the
one of clay. The brick one is a cubit high,
a foot wide on the inside, and one foot
two digits long; at a point five digits
above the hearth—which is
usually the thickness of an unbaked
an iron plate is laid, and smeared over with lute on the
upper side to prevent
it from being injured by the fire; in front of
the furnace above the plate is a
mouth a palm high, five digits wide,
and rounded at the top. The iron plate
A—OPENINGS IN THE PLATE. B—PART OF PLATE WHICH PROJECTS BEYOND
THE FURNACE.
has three openings which are one digit wide and three
digits long, one is at
each side and the third at the back; through
them sometimes the ash falls
from the burning charcoal, and sometimes
the draught blows through the
chamber which is below the iron plate,
and stimulates the fire. For this
reason this furnace when used by metallurgists is named from
assaying, but
when used by the alchemists it is named from the
windThe part of the
iron plate which projects from the furnace is generally
three-quarters of a
can be placed quickly in
the furnace through its mouth with a pair of tongs,
or again, if
necessary, can be taken out of the furnace and laid there.
The iron assay furnace is made of four iron bars a foot and a half high,
which at the bottom are bent outward and broadened a short distance to
enable
them to stand more firmly; the front part of the furnace is made
from two
of these bars, and the back part from two of them; to these
bars on both
sides are joined and welded three iron cross-bars, the
first at a height of a palm
from the bottom, the second at a height of
a foot, and the third at the top. The upright bars are perforated at that point where the side cross-bars are
joined to them, in order that three similar iron bars on the remaining
sides
can be engaged in them; thus there are twelve cross-bars, which
make
three stages at unequal intervals. At the lower stage, the upright bars are
distant from each other one
foot and five digits; and at the middle stage the
front is distant from
the back three palms and one digit, and the sides are
distant from each
other three palms and as many digits; at the highest stage
from the
front to the back there is a distance of two palms, and between the
sides three palms, so that in this way the furnace becomes narrower at
the
top. Furthermore, an iron rod, bent to the shape of the mouth, is set into
the lowest bar of the front; this mouth, just like that of the brick
furnace,
is a palm high and five digits wide. Then the front cross-bar of the lower
stage is perforated on each side
of the mouth, and likewise the back one;
through these perforations
there pass two iron rods, thus making altogether
four bars in the lower
stage, and these support an iron plate smeared with
lute; part of this
plate also projects outside the furnace. The outside of
the furnace from the lower stage to the upper, is covered
with iron plates,
which are bound to the bars by iron wires, and
smeared with lute to enable
them to bear the heat of the fire as long
as possible.
As for the clay furnace, it must be made of fat, thick clay, medium so
far as relates to its softness or hardness. This furnace has exactly the same
height as the iron one, and its base
is made of two earthenware tiles, one
foot and three palms long and one
foot and one palm wide. Each side of the
fore part of both tiles is gradually cut away for the
length of a palm, so
that they are half a foot and a digit wide, which
part projects from the
furnace; the tiles are about a digit and a half
thick. The walls are similarly
of clay, and are set on the lower tiles at a
distance of a digit from the edge,
and support the upper tiles; the
walls are three digits high and have four
openings, each of which is
about three digits high; those of the back part and
of each side are
five digits wide, and of the front, a palm and a half wide, to
enable
the freshly made cupels to be conveniently placed on the hearth, when
it has been thoroughly warmed, that they may be dried there. Both tiles
are bound on the outer edge with iron wire, pressed into
them, so that they
will be less easily broken; and the tiles, not
unlike the iron bed-plate, have
three openings three digits long and a
digit wide, in order that when the upper
one on account of the heat of
the fire or for some other reason has become
damaged, the lower one may
be exchanged and take its place. Through these
air blows into the furnace after
passing through the openings in the walls of
the chamber. The furnace is rectangular, and inside at the lower part it is
three
palms and one digit wide and three palms and as many digits long. At
the upper part it is two palms and three digits wide, so that it also
grows
narrower; it is one foot high; in the middle of the back it is
cut out at
the bottom in the shape of a semicircle, of half a digit
radius. Not
unlike the furnace before described, it has in its forepart a mouth
which is
rounded at the top, one palm high and a palm and a digit wide. Its door
is also made of clay, and this has a window and a handle; even
the lid
of the furnace which is made of clay has its own handle,
fastened on with iron
wire. The outer parts and sides of this furnace are bound with iron wires,
which are usually pressed in, in the shape of triangles. The brick furnaces
must remain stationary; the clay and iron ones can be
carried from one
place to another. Those of brick can be prepared more quickly, while those
of iron are
more lasting, and those of clay are more suitable. Assayers
also make temporary furnaces in another way; they stand three
bricks
on a hearth, one on each side and a third one at the back, the
fore-part lies
open to the draught, and on these bricks is placed an
iron plate, upon which
they again stand three bricks, which hold and
retain the charcoal.
The setting of one furnace differs from another, in that some are placed
higher and others lower; that one is placed higher, in which the man
who is
assaying the ore or metals introduces the scorifier through the
mouth with the
tongs; that one is placed lower, into which he
introduces the crucible
through its open top.
In some cases the assayer uses an iron hoop
this is placed upon the hearth
of a chimney, the lower edge being daubed
with lute to prevent the
blast of the bellows from escaping under it. If the blast is given slowly, the ore will be smelted and the copper will
melt in
the triangular crucible, which is placed in it and taken away
again with the
tongs. The hoop is two palms high and half a digit thick; its diameter is
generally one foot and one palm, and where the blast from the bellows
enters
into it, it is notched out. The bellows is a double one, such as goldworkers
use, and sometimes
smiths. In the middle of the bellows there is a board in
which there is an
air-hole, five digits wide and seven long, covered by a
little flap
which is fastened over the air-hole on the lower side of the board;
this flap is of equal length and width. The bellows, without its head, is
three feet long, and at the back is
one foot and one palm wide and
somewhat rounded, and it is three palms
wide at the head; the head itself
is three palms long and two palms and
a digit wide at the part where it joins
the boards, then it gradually
becomes narrower. The nozzle, of which there
is only one, is one foot and two digits long;
this nozzle, and one-half of the
head in which the nozzle is fixed, are
placed in an opening of the wall, this
being one foot and one palm
thick; it reaches only to the iron hoop on the The hide of the bellows is
fixed to the bellows-boards with its own
peculiar kind of iron nails. It joins
both bellows-boards to the head, and over it there are cross
strips of
hide fixed to the bellows-boards with broad-headed nails, and
similarly
fixed to the head. The middle board of the bellows rests on an iron bar,
to which it is
fastened with iron nails clinched on both ends, so that it cannot
move;
the iron bar is fixed between two upright posts, through which it
penetrates. Higher up on these upright posts there is a wooden axle, with
iron
journals which revolve in the holes in the posts. In the middle of
this axle there is mortised a lever, fixed with iron
nails to prevent it from
flying out; the lever is five and a half feet
long, and its posterior end is
engaged in the iron ring of an iron rod
which reaches to the “tail” of the
lowest bellows-board,
and there engages another similar ring. And so when
the workman pulls down the lever, the lower part of the
bellows is raised and
drives the wind into the nozzle; then the wind,
penetrating through the hole
in the middle bellows-board, which is
called the air-hole, lifts up the upper
part of the bellows, upon whose
upper board is a piece of lead, heavy enough
to press down that part of
the bellows again, and this being pressed down
blows a blast through
the nozzle. This is the principle of the double bellows,
which is peculiar to the
iron hoop where are placed the triangular crucibles in
which copper ore
is smelted and copper is melted.
A—IRON HOOP. B—DOUBLE BELLOWS. C—ITS NOZZLE.
D—LEVER.
I have spoken of the furnaces and the iron hoop; I will now speak of
the
muffles and the crucibles. The muffle is made of clay, in the shape
of an inverted gutter tile; it
covers the scorifiers, lest coal dust fall into
them and interfere with
the assay. It is a palm and a half broad, and the
height, which corresponds with
the mouth of the furnace, is generally a palm,
the
mouth of the furnace, everywhere else on the sides and at the back
there is a space of three digits, to allow the charcoal to lie in the
open space
between it and the furnace. The muffle is as thick as a fairly thick earthen
jar; its upper part is
entire; the back has two little windows, and each side
has two or three
or even four, through which the heat passes into the scorifiers
and
melts the ore. In place of little windows, some muffles have small holes,
ten in the
back and more on each side. Moreover, in the back below the
little windows, or small holes, there
are cut away three semi-circular notches
half a digit high, and on each
side there are four. The back of the muffle
is generally a little lower than the front.
A—BROAD LITTLE WINDOWS OF MUFFLE. B—NARROW ONES. C—OPENINGS
IN THE
BACK THEREOF.
The crucibles differ in the materials from which they are made, because
they are made of either clay or ashes; and those of clay, which we also
call
“earthen,” differ in shape and size. Some are made in the shape of a mod
erately thick salver
(scorifiers), three digits wide, and of a capacity of an
by those who
assay gold or silver ore. Some are triangular and much
thicker and more capacious, holding five,
or six, or even more
these copper is melted, so that it can be
poured out, expanded, and tested
with fire, and in these copper ore is
usually melted.
The cupels are made of ashes; like the preceding scorifiers they are
tray-shaped, and their lower part is very thick but their capacity is
less. In these lead is separated from silver, and by them assays are concluded.
Inasmuch as the assayers themselves make the cupels, something must
be
said about the material from which they are made, and the method
of
making them. Some make them out of all kinds of ordinary ashes; these
are not good,
because ashes of this kind contain a certain amount of fat,
whereby
such cupels are easily broken when they are hot. Others make
them likewise out of any kind of ashes which have been
previously
leached; of this kind are the ashes into which warm water
has been infused
for the purpose of making lye. These ashes, after being dried in the sun or
a furnace, are sifted in a
hair sieve; and although warm water washes away the
A—SCORIFIER. B—TRIANGULAR CRUCIBLE. C—CUPEL.
fat from
the ashes, still the cupels which are made from such ashes are not
very
good because they often contain charcoal dust, sand, and pebbles. Some make them in the same way out of any kind of ashes, but first of all
pour water into the ashes and remove the scum which floats thereon;
then,
after it has become clear, they pour away the water, and dry the
ashes; they
then sift them and make the cupels from them. These, indeed, are good,
but not of the best quality, because ashes of
this kind are also not devoid of
small pebbles and sand. To enable cupels of the best quality to be made, all
the impurities must
be removed from the ashes. These impurities are of
two kinds; the one sort light, to which class
belong charcoal dust and fatty
material and other things which float in
water, the other sort heavy, such
as small stones, fine sand, and any
other materials which settle in the
bottom of a vessel. Therefore, first of all, water should be poured into the
ashes and the
light impurities removed; then the ashes should be
kneaded with the
hands, so that they will become properly mixed with
the water. When the water has become muddy and turbid, it should be
poured into a
second vessel. In this way the small stones and fine sand, or
any other heavy substance
which may be there, remain in the first vessel,
and should be thrown
away. When all the ashes have settled in this second
vessel, which will be
shown if the water has become clear and does not taste
of the flavour
of lye, the water should be thrown away, and the ashes
which have
settled in the vessel should be dried in the sun or in a furnace. This material is suitable for the cupels, especially if it is the ash of
beech
wood or other wood which has a small annual growth; those ashes
made
from twigs and limbs of vines, which have rapid annual growth, are
not so
frequently crack and break in the fire and
absorb the metals. If ashes of
beech or similar wood are not to be had, the assayer makes
little balls of such
ashes as he can get, after they have been cleared
of impurities in the manner
before described, and puts them in a
baker's or potter's oven to burn, and from
these the cupels are made,
because the fire consumes whatever fat or damp
there may be. As to all kinds of ashes, the older they are the better, for it is
necessary that they should have the greatest possible dryness. For this
reason ashes obtained from burned bones, especially from the
bones of the
heads of animals, are the most suitable for cupels, as are
also those ashes
obtained from the horns of deer and the spines of
fishes. Lastly, some take the
ashes which are obtained from burnt scrapings of
leather, when the tanners
scrape the hides to clear them from hair. Some prefer to use compounds,
that one being recommended which has one
and a half parts of ashes from the
bones of animals or the spines of
fishes, and one part of beech ashes, and half a
part of ashes of burnt
hide scrapings. From this mixture good cupels are
made, though far better ones are
obtained from equal portions of ashes of
burnt hide scrapings, ashes of
the bones of heads of sheep and calves, and
ashes of deer horns. But the best of all are produced from deer horns alone,
burnt to powder;
this kind, by reason of its extreme dryness, absorbs metals
least of
all. Assayers of our own day, however, generally make the
cupels from beech
ashes. These ashes, after being prepared in the
manner just described, are
first of all sprinkled with beer or water, to make
them stick together,
and are then ground in a small mortar. They are ground
again after being mixed with the ashes obtained from the
skulls of beasts or from
the spines of fishes; the more the ashes are
ground the better they are. Some rub bricks and sprinkle the dust so obtained, after sifting it, into the
beech ashes, for dust of this kind does not allow the hearth-lead to
absorb
the gold or silver by eating away the cupels. Others, to guard against the
same thing, moisten the cupels with white
of egg after they have been made,
and when they have been dried in the
sun, again crush them; especially if they
want to assay in it an ore or
copper which contains iron. Some moisten the
ashes again and again with cow's milk, and dry them,
and grind them in a
small mortar, and then mould the cupels. In the works in which silver
is separated from copper, they make cupels
from two parts of the ashes of
the crucible of the cupellation furnace,
for these ashes are very dry, and from
one part of bone-ash. Cupels which have been made in these ways also
need to be placed in the
sun or in a furnace; afterward, in whatever way
they have been made,
they must be kept a long time in dry places, for the
older they are,
the dryer and better they are.
Not only potters, but also the assayers themselves, make scorifiers
and
triangular crucibles. They make them out of fatty clay, which is
dryWith this clay they mix the dust of old
broken crucibles, or of burnt
and worn bricks; then they knead with a
pestle the clay thus mixed with
dust, and then dry it. As to these crucibles,
The moulds in which the
cupels are moulded are of two kinds, that is, a
smaller size and a larger size. In the smaller ones are made the cupels in which silver or gold is purged
from the lead which has absorbed it; in the larger ones are made cupels
in
which silver is separated from copper and lead. Both moulds are made out
of brass and have no bottom, in order that the
cupels can be taken out of
them whole. The pestles also are of two kinds, smaller and larger, each
likewise of
brass, and from the lower end of them there projects a round
knob, and
this alone is pressed into the mould and makes the hollow part of
the
cupel. The part which is next to the knob corresponds to the upper
part of the
mould.
A—LITTLE MOULD. B—INVERTED MOULD. C—PESTLE. D—ITS
KNOB. E—SECOND
PESTLE.
So much for these matters.
I will now speak of the preparation of the
ore for assaying. It is prepared by roasting, burning, crushing, and wash
ing. It is necessary to take a fixed weight of ore in order that one may
determine how great a portion of it these preparations consume. The
hard stone containing the metal is burned in order that, when its
hardness
has been overcome, it can be crushed and washed; indeed, the
very hardest
kind, before it is burned, is sprinkled with vinegar, in
order that it may more
rapidly soften in the fire. The soft stone should be broken with a hammer,
crushed in a mortar and
reduced to powder; then it should be washed
and then dried again. If earth is mixed with the mineral, it is washed in a
basin, and that
which settles is assayed in the fire after it is dried. All mining
products which are washed must again be dried. But ore which is rich in
metal is neither burned nor crushed nor washed,
but is roasted, lest that
method of preparation should lose some of the
metal. When the fires have
up with lute. A less valuable ore is even burned on a hearth, being placed
upon the
charcoal; for we do not make a great expenditure upon metals, if
they
are not worth it. However, I will go into fuller details as to all these
methods of
preparing ore, both a little later, and in the following Book.
For the present, I have decided to explain those things which mining
people usually call fluxes
assaying, but also for
smelting. Great power is discovered in all these fluxes,
but we do not see the
same effects produced in every case; and some are of a
very complicated
nature. For when they have been mixed with the ore
and are melted in either the
assay or the smelting furnace, some of them,
because they melt easily,
to some extent melt the ore; others, because they
either make the ore
very hot or penetrate into it, greatly assist the fire in
separating
the impurities from the metals, and they also mix the fused part
with
the lead, or they partly protect from the fire the ore whose metal contents
would be either consumed in the fire, or carried up with the fumes and
fly out
of the furnace; some fluxes absorb the metals. To the first order be
longs lead, whether it be reduced to little
granules or resolved into ash by
fire, or red-lead
slags of
gold, silver, copper, and lead; also soda
alum, vitriol,
in hot furnaces, the sand which is made from themBut lead, its ashes, red-lead, ochre, and
litharge, are more efficacious
for ores which melt easily; hearth-lead for
those which melt with
difficulty; and galena for those which melt with
greater difficulty. To the second order belong iron filings, their slag,
artificíosus,
gold from silver
into ore, the argol
to a considerable degree, the lees of vinegar to a greater
degree, but
most of all those of the
filings and slags of iron, since
they melt more slowly, have the power of heat
ing the ore. To the third order belong pyrites, the cakes which are melted
from them,
soda, its slags, salt, iron, iron scales, iron filings, iron slags, vitriol,
the sand which is resolved from stones which easily melt in the fire,
and
they
absorb the metals of the ore and guard them from the fire which
con
sumes them. To the fourth order belong lead and copper, and their relations.
And so with regard to fluxes, it is manifest that some are natural, others
fall in the category of slags, and the rest are purged from slag. When we
sort of flux, but when we smelt them
we cannot add a large portion without
great expense. We must, therefore, consider how great the cost is, to avoid
incurring a
greater expense on smelting an ore than the profit we make out of
the
metals which it yields.
The colour of the fumes which the ore emits after being placed on a hot
shovel or an iron plate, indicates what flux is needed in addition to
the lead,
for the purpose of either assaying or smelting. If the fumes have a purple
tint, it is best of all, and the ore does not
generally require any flux whatever. If the fumes are blue, there should be added cakes melted out of pyrites or
other cupriferous rock; if yellow, litharge and sulphur should be
added; if
red, glass-galls
litharge, and glass-galls; if the fumes are black, melted salt or iron
slag,
litharge and white lime rock. If they are white, sulphur and iron which is
eaten with rust; if they
are white with green patches, iron slag and
sand obtained from stones
which easily melt; if the middle part of the
fumes are yellow and
thick, but the outer parts green, the same sand and
iron slag. The colour of the fumes not only gives us information as to the
proper
remedies which should be applied to each ore, but also more or less
indication as to the solidified juices which are mixed with it, and
which give
forth such fumes. Generally, blue fumes signify that the ore contains azure;
yellow,
orpiment; red, realgar; green, chrysocolla; black, black bitumen;
white, tin
the middle part yellow and
other parts green show that it contains sulphur. Earth, however, and other things dug up which contain metals,
some
times emit similarly coloured fumes.
If the ore contains any
then
are added cakes melted from a cupriferous stone and sand made from
stones which easily melt. If the ore contains iron, then pyrites and sulphur
are added; for just
as iron slag is the flux for an ore mixed with sulphur, so
on the
contrary, to a gold or silver ore containing iron, from which they are
easily melt.
By the first method, equal portions of argol, lees of vinegar, and urine,
are all boiled down together till turned into salt. The second method is from
equal portions of the ashes which wool-dyers
use, of lime. of argol purified,
and of melted salt; one
twenty
and
afterward there is added to what remains one
of unmelted salt, eight
pounds of lye being at the same time poured into
the pots, with
litharge smeared around on the inside, and the whole is boiled
till the
salt becomes thoroughly dry. The third method follows.
Unmelted
salt, and iron which is eaten with rust, are put into a vessel,
and after
urine has been poured in, it is covered with a lid and put in
a warm place
for thirty days; then the iron is washed in the urine and
taken out, and
the residue is boiled until it is turned into salt. In the fourth method by
which
lime and the ashes which wool-dyers
use, together with equal portions of
salt, soap, white argol, and
saltpetre, are boiled until in the end the mix
ture evaporates and
becomes salt. This salt is mixed with the concentrates
from washing, to melt them.
Saltpetre is prepared in the following manner, in order that it may be
suitable for use in assaying ore. It is placed in a pot which is smeared on
the inside with litharge, and
lye made of quicklime is repeatedly poured over
it, and it is heated
until the fire consumes it. Wherefore the saltpetre
does not kindle with the fire, since it has
absorbed the lime which preserves
it, and thus it is prepared
The following compositions
the heat of fire breaks up or melts
only with difficulty. Of these, one is made
from stones of the third order, which easily melt
when thrown into hot
furnaces. They are crushed into pure white powder, and with half an
This mixture is put into a scorifier large enough to hold it, and placed
under
the muffle of a hot furnace; when the charge flows like water,
which occurs
after half an hour, it is taken out of the furnace and
poured on to a stone,
and when it has hardened it has the appearance of
glass, and this is likewise
crushed. This powder is sprinkled over any metalliferous ore which does
not
easily melt when we are assaying it, and it causes the slag to exude.
Others, in place of litharge, substitute lead ash,
following way:
sulphur is thrown into lead which has been melted in a
crucible, and it
soon becomes covered with a sort of scum; when this is
removed, sulphur
is again thrown in, and the skin which forms is again taken
off; this
is frequently repeated, in fact until all the lead is turned into
powder. There is a powerful flux compound which is made from one
each of prepared saltpetre,
melted salt, glass-gall, and argol, and one-third
of an
added to an equal weight of ore, liquefies it. A more powerful flux is made by
placing together in a pot, smeared on
the inside with litharge, equal portions
of white argol, common salt,
and prepared saltpetre, and these are heated
until a white powder is
obtained from them, and this is mixed with as much
litharge; one part
of this compound is mixed with two parts of the ore which
is to be
assayed. A still more powerful flux than this is made out of ashes
of black lead,
saltpetre, orpiment,
which gold workers separate
gold from silver. The ashes of lead
one pound of lead and one pound of sulphur; the lead is flattened out
into
sheets by pounding with a hammer, and placed alternately with
sulphur in a
crucible or pot, and they are heated together until the
fire consumes the
sulphur and the lead turns to ashes. One
with one
in an iron pan until they liquefy; they are then poured out, and
after cool
ing are again ground to powder. A
dried
lees (
point at which they form a
button, which is similarly reduced to powder. A
powder made out of the saltpetre and orpiment,
are mixed together and a
liquefies it and cleanses
it of dross. But the most powerful flux is one which
has two
the following,—
prepared saltpetre, litharge,
vitriol, argol, salt obtained from ashes of musk ivy,
dried lees of the
alum reduced by fire to powder,
and one
sulphur and ground into powder. A half or whole portion of this mixture,
as the necessity of the case
requires, is mixed with one portion of the ore
and two portions of
lead, and put in a scorifier; it is sprinkled with powder
of crushed
Venetian glass, and when the mixture has been heated for an hour
and a
half or two hours, a button will settle in the bottom of the scorifier, and
from it the lead is soon separated.
There is also a flux which separates sulphur, orpiment and realgar from
metalliferous ore. This flux is composed of equal portions of iron slag,
white After these juices have been secreted, the ores
themselves are melted,
with argol added to them. There is one flux which
preserves
which preserves the metals from the
portions of sulphur, prepared saltpetre,
melted salt, and vitriol, heated
together in lye until no odour
emanates from the sulphur, which occurs after
a space of three or four
hours.
It is also worth while to substitute certain other mixtures.
Take two
portions of ore properly prepared, one portion of iron filings,
and likewise
one portion of salt, and mix; then put them into a
scorifier and place them
in a muffle furnace; when they are reduced by
the fire and run together, a
button will settle in the bottom of the
scorifier. Or else take equal portions
of ore and of lead ochre, and mix with them
a small quantity of iron filings,
and put them into a scorifier, then
scatter iron filings over the mixture. Or
else take ore which has been ground to powder and sprinkle it in a
crucible,
and then sprinkle over it an equal quantity of salt that has
been three or
four times moistened with urine and dried; then, again
and again alternately,
powdered ore and salt; next, after the crucible
has been covered with a
lid and sealed, it is placed upon burning
charcoal. Or else take one portion of
ore, one portion of minute lead granules,
half a portion of Venetian glass,
and the same quantity of glass-galls. Or else take one portion of ore, one
portion of lead granules, half a
portion of salt, one-fourth of a portion of argol,
and the same
quantity of lees of the Or else take equal portions of prepared ore and a powder in which there
iron slag Or else take equal portions of gold
ore, vitriol, argol, and of salt. So much for the fluxes.
In the assay furnace, when it has been prepared in the way in which I
have described, is first placed a muffle. Then selected pieces of live charcoals
are laid on it, for, from pieces
of inferior quality, a great quantity of ash collects
around the muffle
and hinders the action of the fire. Then the scorifiers are
placed under the muffle with tongs, and glowing
coals are placed under the
fore part of the muffle to warm the
scorifiers more quickly; and when the lead
or ore is to be placed in
the scorifiers, they are taken out again with the
tongs. When the scorifiers glow in the heat, first of all the ash or small
charcoals, if any have fallen into them, should be blown away with an
iron
pipe two feet long and a digit in diameter; this same thing must
be done
if ash or small coal has fallen into the cupels. Next, put in a small ball of lead
with the tongs, and when this lead has
begun to be turned into fumes and
consumed, add to it the prepared ore
wrapped in paper. It is preferable that
the assayer should wrap it in paper, and in this
way put it in the scorifier,
than that he should drop it in with a
copper ladle; for when the
scorifiers are small, if he uses a ladle he
frequently spills some part of the
ore. When the paper is burnt, he stirs the ore with a small charcoal held in
the tongs, so that the lead may absorb the metal which is mixed in the
ore;
when this mixture has taken place, the slag partly adheres by its
cir
cumference to the scorifier and makes a kind of black ring, and
partly
floats on the lead in which is mixed the gold or silver; then
the slag must
be removed from it.
The lead used must be entirely free from every trace of silver, as is that
which is known as
must be assayed separately, to
determine with certainty that proportion of
silver it contains, so that
it may be deducted from the calculation of the
ore, and the result be
exact; for unless such lead be used, the assay will be
false and
misleading. The lead balls are made with a pair of iron tongs,
about one foot long;
its iron claws are so formed that when pressed
together they are
egg-shaped; each claw contains a hollow cup, and when
the claws are
closed there extends upward from the cup a passage, so there
are two
openings, one of which leads to each hollow cup. And so when the
molten lead is poured in through the openings, it flows
down into the hollow
cup, and two balls are formed by one pouring.
In this place I ought not to omit mention of another method of assaying
employed by some assayers. They first of all place prepared ore in the
scorifiers and heat it, and
afterward they add the lead. Of this method I
cannot approve, for in this way the ore frequently
becomes cemented, and
for this reason it does not stir easily
afterward, and is very slow in mixing
with the lead.
If the whole space of the furnace covered by the muffle is not filled with
scorifiers, cupels are put in the empty space, in order that they may
become
warmed in the meantime. Sometimes, however, it is filled with scorifiers,
when we are assaying
many different ores, or many portions of one ore at the
same time. Although the cupels are usually dried in one hour, yet smaller
ones are
done more quickly, and the larger ones more slowly. Unless the
cupels are heated before the metal mixed with lead is placed
in them, they
A—CLAWS OF THE TONGS. B—IRON, GIVING FORM OF AN EGG.
C—OPENING.
frequently break, and the lead always sputters and
sometimes leaps out of them;
if the cupel is broken or the lead leaps
out of it, it is necessary to assay
another portion of ore; but if the
lead only sputters, then the cupels should
be covered with broad thin
pieces of glowing charcoal, and when the lead
strikes these, it falls
back again, and thus the mixture is slowly exhaled. Further, if in the cupellation the lead which is in the mixture is not
con
sumed, but remains fixed and set, and is covered by a kind of
skin, this is a
sign that it has not been heated by a sufficiently hot
fire; put into the
mixture, therefore, a dry pine stick, or a twig of a
similar tree, and hold it
in the hand in order that it can be drawn
away when it has been heated. Then take care that the heat is sufficient and equal; if the heat has not
passed all round the charge, as it should when everything is done
rightly,
but causes it to have a lengthened shape, so that it appears
to have a tail,
this is a sign that the heat is deficient where the
tail lies. Then in order
that the cupel may be equally heated by the fire, turn it
around with a small
iron hook, whose handle is likewise made of iron
and is a foot and a half long.
SMALL IRON HOOK.
Next, if the mixture has not enough lead, add as much of it as is required
with the iron tongs, or with the brass ladle to which is fastened a
very long
handle. In order that the charge may not be cooled, warm the lead beforehand.
needs melting, rather than afterward when the
melting has been half finished,
that the whole quantity may not vanish
in fumes, but part of it remain
fast. When the heat of the fire has nearly consumed the lead, then is the
time
when the gold and silver gleam in their varied colours, and when all the
lead has been consumed the gold or silver settles in the cupel. Then as
soon as possible remove the cupel out of the furnace, and take
the button out
of it while it is still warm, in order that it does not
adhere to the ashes. This
generally happens if the button is already cold when it is taken
out. If the
ashes do adhere to it, do not scrape it with a knife, lest some
of it be lost and
the assay be erroneous, but squeeze it with the iron
tongs, so that the ashes
drop off through the pressure. Finally, it is of advantage to make two or
three assays of the same ore
at the same time, in order that if by chance
one is not successful, the
second, or in any event the third, may be certain.
While the assayer is assaying the ore, in order to prevent the great heat
of the fire from injuring his eyes, it will be useful for him always to
have
ready a thin wooden tablet, two palms wide, with a handle by which
it may
be held, and with a slit down the middle in order that he may
look through
it as through a crack, since it is necessary for him to
look frequently within
and carefully to consider everything.
A—HANDLE OF TABLET. B—ITS CRACK.
Now the lead which has absorbed the silver from a metallic ore is
con
sumed in the cupel by the heat in the space of three quarters
of an hour. When
the assays are completed the muffle is taken out of the furnace,
and the
ashes removed with an iron shovel, not only from the brick and
iron furnaces,
but also from the earthen one, so that the furnace need
not be removed from
its foundation.
From ore placed in the triangular crucible a button is melted out, from
which metal is afterward made. First of all, glowing charcoal is put into
the iron hoop, then is put in
the triangular crucible, which contains the ore
together with those
things which can liquefy it and purge it of its dross;
then the fire is
blown with the double bellows, and the ore is heated until
the button
settles in the bottom of the crucible. We have explained that
there are two methods of assaying ore,—one,
by which the lead is mixed
the other, by which it
is first melted in the triangular earthen crucible and
afterward mixed
with lead in the scorifier, and later separated from it in the
cupel. Now let us consider which is more suitable for each ore, or, if neither
is suitable, by what other method in one way or another we can assay
it.
We justly begin with a gold ore, which we assay by both methods, for
if
it is rich and seems not to be strongly resistant to fire, but to liquefy
easily,
one
one and a half, or two
and placed in the scorifier, and the two
are heated in the fire until they are
well mixed. But since such an ore sometimes resists melting, add a little
salt to
it, either
prevent the alloy from collecting much dross;
stir it frequently with an iron
rod, in order that the lead may flow
around the gold on every side, and absorb
it and cast out the waste. When this has been done, take out the alloy and
cleanse it of slag; then
place it in the cupel and heat it until it exhales all
the lead, and a
bead of gold settles in the bottom.
If the gold ore is seen not to be easily melted in the fire, roast it and
extinguish it with brine. Do this again and again, for the more often you
roast it and extinguish
it, the more easily the ore can be crushed fine, and the
more quickly
does it melt in the fire and give up whatever dross it possesses.
three parts of some powder compound which
melts ore, and six parts of lead. Put the charge into the triangular crucible, place it in the iron hoop to
which
the double bellows reaches, and heat first in a slow fire, and
afterward
gradually in a fiercer fire, till it melts and flows like
water. If the ore does
not melt, add to it a little more of these fluxes, mixed
with an equal portion
of yellow litharge, and stir it with a hot iron
rod until it all melts. Then
take the crucible out of the hoop, shake off the button when it has
cooled,
and when it has been cleansed, melt first in the scorifier and
afterward in
the cupel. Finally, rub the gold which has settled in the bottom of the cupel,
after it has been taken out and cooled, on the touchstone, in order to
find out
what proportion of silver it contains. Another method is to put a
pondium
add to it a
If it resists melting,
add half a
same quantity of roasted lees of vinegar, or lees of the
gold
from silver, and the button will settle in the bottom of the crucible.
Melt this button again in the scorifier and a third time in the cupel.
We determine in the following way, before it is melted in the muffle
furnace, whether pyrites contains gold in it or not: if, after being
three times
roasted and three times quenched in sharp vinegar, it has
not broken nor
changed its colour, there is gold in it. The vinegar by which it is quenched
should be mixed with salt that is
put in it, and frequently stirred and dissolved
for three days. Nor is pyrites devoid of gold, when, after being roasted and
then rubbed
on the touchstone, it colours the touchstone in the same way that
it
coloured it when rubbed in its crude state. Nor is gold lacking in that,
whose concentrates from washing, when
heated in the fire, easily melt, giving
forth little smell and
remaining bright; such concentrates are heated in the
fire in a
hollowed piece of charcoal covered over with another charcoal.
We also assay gold ore without fire, but more often its sand or the
con
centrates which have been made by washing, or the dust gathered
up by
some other means. A little of it is slightly moistened with water and heated
until it
begins to exhale an odour, and then to one portion of ore are placed
two portions of quicksilverThey are
mixed together with a little brine, and are then ground with a
wooden pestle
for the space of two hours, until the mixture becomes of
the thickness of dough,
and the quicksilver can no longer be
distinguished from the concentrates
made by the washing, nor the
concentrates from the quicksilver. Warm, or
at least tepid, water is poured into the dish and the material
is washed until
the water runs out clear. Afterward cold water is poured into the same dish,
and soon the
quicksilver, which has absorbed all the gold, runs together
into a
separate place away from the rest of the concentrates made by
washing. The quicksilver is afterward separated from the gold by means
of a pot
covered with soft leather, or with canvas made of woven
threads of
cotton; the amalgam is poured into the middle of the cloth or
over and tied with a waxed string, and the dish
catches the quicksilver
which is squeezed through it. As for the gold which remains in the leather,
it is placed in a
scorifier and purified by being placed near glowing coals. Others
do not wash away the dirt with warm water, but with strong lye
and vinegar,
for they pour these liquids into the pot, and also throw
into it the quicksilver
mixed with the concentrates made by washing. Then they set the pot in a
warm place, and after twenty-four hours pour
out the liquids with the dirt, and
separate the quicksilver from the
gold in the manner which I have described. Then they pour urine into a jar set in the ground, and in the jar place a
pot with holes in the bottom, and in the pot they place the gold; then
the
lid is put on and cemented, and it is joined with the jar; they
afterward heat
it till the pot glows red. After it has cooled, if there is copper in the gold
they melt it with
lead in a cupel, that the copper may be separated from it;
but if there
is silver in the gold they separate them by means of the
which has the power
of parting these two metals. There are some who,
when they separate gold from quicksilver, do not
pour the amalgam into
a leather, but put it into a gourd-shaped earthen
vessel, which they place
in the furnace and heat gradually over burning
charcoal; next, with an iron
plate, they cover the opening of the
operculum, which exudes vapour, and as
soon as it has ceased to exude,
they smear it with lute and heat it for a short
time; then they remove
the operculum from the pot, and wipe off the
quicksilver which adheres
to it with a hare's foot, and preserve it for future
use. By the latter method, a greater quantity of quicksilver is lost, and by
the former method, a smaller quantity.
If an ore is rich in silver, as is
or rarely ruby silver, gray silver, black
silver, brown silver, or yellow silver,
as soon as it is cleansed and
heated, a
it is placed in an
exhales. But if the ore is of poor or moderate quality, it must first be dried,
then crushed, and then to a
of lead is
added, and it is heated in the scorifier until it melts. If it is not
soon melted by the fire, it should be sprinkled with a
little powder of the
first order of fluxes, and if then it does not
melt, more is added little by little
until it melts and exudes its
slag; that this result may be reached sooner,
the powder which has been
sprinkled over it should be stirred in with an iron
rod. When the scorifier has been taken out of the assay furnace, the alloy
should be poured into a hole in a baked brick; and when it has cooled
and been
cleansed of the slag, it should be placed in a cupel and
heated until it exhales
all its lead; the weight of silver which
remains in the cupel indicates what
proportion of silver is contained
in the ore.
We assay copper ore without lead, for if it is melted with it, the copper
usually exhales and is lost. Therefore, a certain weight of such an ore
cooled, it is crushed and washed; then the concentrates made by washing
are again roasted, crushed, washed, dried, and weighed. The portion which
it has lost whilst it is being roasted and washed is
taken into account, and
these concentrates by washing represent the
cake which will be melted out
of the copper ore. Place three
with three
and
Venetian glass, mixed, into the triangular crucible, and place it in the
iron
hoop which is set on the hearth in front of the double bellows. Cover the crucible
with charcoal in such a way that nothing may fall
into the ore which is to be
melted, and so that it may melt more
quickly. At first blow a gentle blast with
the bellows in order that the ore may
be heated gradually in the fire; then
blow strongly till it melts, and
the fire consumes that which has been added to
it, and the ore itself
exudes whatever slag it possesses. Next, cool
the crucible which has been taken out, and when this is
broken you will find
the copper; weigh this, in order to ascertain how
great a portion of the ore
the fire has consumed. Some ore is only once roasted, crushed, and washed;
and of this kind of
concentrates, three
taken with one
galls. Heat them in the triangular crucible, and when the mixture has
cooled a
button of pure copper will be found, if the ore is rich in this metal.
If, however, it is less rich, a stony lump results, with which the copper is
intermixed; this lump is again roasted, crushed, and, after adding
stones
which easily melt and saltpetre, it is again melted in another
crucible, and
there settles in the bottom of the crucible a button of
pure copper. If you
wish to know what proportion of silver is in this copper button,
melt it in a
cupel after adding lead. With regard to this test I will speak later.
Those who wish to know quickly what portion of silver the copper ore
contains, roast the ore, crush and wash it, then mix a little yellow
litharge
with one
mixture into a scorifier, which they place under the muffle in a hot
furnace for
the space of half an hour. When the slag exudes, by reason of the melting force
which is in the
litharge, they take the scorifier out; when it has cooled, they
cleanse
it of slag and again crush it, and with one
mix one
and a half They then put it into another
scorifier, which they place under the
muffle in a hot furnace, adding to the
mixture a little of the powder
of some one of the fluxes which cause ore to
melt; when it has melted
they take it out, and after it has cooled, cleanse
it of slag; lastly,
they heat it in the cupel till it has exhaled all of the lead,
and only
silver remains.
Lead ore may be assayed by this method: crush half an
pure lead-stone and the
same quantity of the
borax, mix them together, place
them in a crucible, and put a glowing coal As soon as the borax crackles and the lead-stone melts,
which soon
occurs, remove the coal from the crucible, and the lead will settle
to
the bottom of it; weigh it out, and take account of that portion of it
which the fire has consumed. If you also wish to know what portion of silver
is contained in the
lead, melt the lead in the cupel until all of it exhales.
Another way is to roast the lead ore, of whatsoever quality it be, wash
it, and put into the crucible one
with three
together, and place it
in the iron hoop that it may melt; when it has cooled,
cleanse it of
its slag, and complete the test as I have already said. Another way is
to take two
glass, or
glass-galls reduced to powder, a Put
the mixture into the triangular crucible, and heat it over a gentle
fire to
prevent it from breaking; when the mixture has melted, blow the
fire
vigorously with the bellows; then take the crucible off the live
coals and
let it cool in the open air; do not pour water on it, lest
the lead button being
acted upon by the excessive cold should become
mixed with the slag, and the
assay in this way be erroneous. When the crucible has cooled, you will find
in the bottom of it the lead
button. Another way is to take two
ore, a
of
saltpetre. If there is difficulty in melting the ore, add to it iron filings,
which, since they increase the heat, easily separate the waste from
lead and
other metals. By the last way, lead ore properly prepared is placed in the
crucible,
and there is added to it only the sand made from stones which easily
melt, or iron filings, and then the assay is completed as formerly.
You can assay tin ore by the following method.
First roast it, then
crush, and afterward wash it; the concentrates are
again roasted, crushed,
and washed. Mix one and a half
pondium
when it
has been moistened with water, make a lump. Afterwards,
perforate a large round piece of charcoal, making this
opening a palm deep,
three digits wide on the upper side and narrower
on the lower side; when
the charcoal is put in its place the latter
should be on the bottom and the
former uppermost. Let it be placed in a crucible, and let glowing coal be
put round it on
all sides; when the perforated piece of coal begins to burn,
the lump
is placed in the upper part of the opening, and it is covered with a
wide piece of glowing coal, and after many pieces of coal have been put
round
it, a hot fire is blown up with the bellows, until all the tin
has run out
of the lower opening of the charcoal into the crucible. Another way is to
take a large piece of charcoal, hollow it out, and
smear it with lute, that the
ore may not leap out when white hot. Next, make a small hole through the
middle of it, then fill up the large
opening with small charcoal, and put the
ore upon this; put fire in the
small hole and blow the fire with the nozzle of
a hand bellows; place
the piece of charcoal in a small crucible, smeared
with lute, in which,
when the melting is finished, you will find a button
of tin.
In assaying bismuth ore, place pieces of ore in the scorifier, and put
it under the muffle in a hot furnace; as soon as they are heated, they
drip with bismuth, which runs together into a button.
Quicksilver ore is usually tested by mixing one part of broken ore
with
three-parts of charcoal dust and a handful of salt. Put the mixture into
a crucible or a pot or a jar, cover it with a lid,
seal it with lute, place it on
glowing charcoal, and as soon as a burnt
cinnabar colour shows in it, take
out the vessel; for if you continue
the heat too long the mixture exhales the
quicksilver with the fumes. The quicksilver itself, when it has become cool, is
found in the bottom
of the crucible or other vessel. Another way is to place
broken ore in a gourd-shaped earthen vessel, put
it in the assay furnace,
and cover with an operculum which has a long
spout; under the spout, put
an ampulla to receive the quicksilver which
distills. Cold water should be
poured into the ampulla, so that the quicksilver
which has been heated by the
fire may be continuously cooled and
gathered together, for the quicksilver
is borne over by the force of
the fire, and flows down through the spout of
the operculum into the
ampulla. We also assay quicksilver ore in the very
same way in which we smelt it. This I will explain in its proper place.
Lastly, we assay iron ore in the forge of a blacksmith.
Such ore is burned,
crushed, washed, and dried; a magnet is laid over
the concentrates, and
the particles of iron are attracted to it; these
are wiped off with a brush,
and are caught in a crucible, the magnet
being continually passed over the
concentrates and the particles wiped
off, so long as there remain any particles
which the magnet can attract
to it. These particles are heated in the crucible
with saltpetre until they
melt, and an iron button is melted out of them. If the magnet easily and quickly attracts the particles to it, we infer that
the
ore is rich in iron; if slowly, that it is poor; if it appears
actually to repel
the ore, then it contains little or no iron. This is enough for the assaying of
ores.
I will now speak of the assaying of the metal alloys.
This is done both
by coiners and merchants who buy and sell metal, and
by miners, but most
of all by the owners and mine masters, and by the
owners and masters of
the works in which the metals are smelted, or in
which one metal is parted
from another.
First I will describe the way assays are usually made to ascertain what
portion of precious metal is contained in base metal. Gold and silver are
now reckoned as precious metals and all the others
as base metals. Once
upon a time the base metals were burned up, in order that the
precious metals
should be left pure; the Ancients even discovered by
such burning what
portion of gold was contained in silver, and in this
way all the silver was
consumed, which was no small loss. However, the famous mathematician,
Archimedes
than a small one. This I will explain in my commentaries.
The
alchemists have shown us a way of separating silver from gold by
which
neither of them is lost
Gold which contains silver,
on the touchstone. Then a needle in which there is a similar amount of
gold or silver is
rubbed on the same touchstone, and from the lines which are
produced in
this way, is perceived what portion of silver there is in the gold,
or
what portion of gold there is in the silver. Next there is added to the
silver which is in the gold, enough silver to
make it three times as much as the
gold. Then lead is placed in a cupel and melted; a little later, a small
amount of copper is put in it, in fact, half an
a
copper. The cupel, when the lead and copper are wanting, attracts the particles
of gold and silver, and absorbs them. Finally, one-third of a
and one
melted; for if the gold and silver were first placed in the cupel and
melted, as I
have already said, it absorbs particles of them, and the
gold, when separated
from the silver, will not be found pure. These metals are heated until the
lead and the copper are consumed, and
again, the same weight of each is melted
in the same manner in another
cupel. The buttons are pounded with a
hammer and flattened out, and each little
leaf is shaped in the form of a
tube, and each is put into a small
glass ampulla. Over these there is poured
one
valens,This is heated over a slow
fire, and small bubbles, resembling pearls in
shape, will be seen to adhere
to the tubes. The redder the
when the redness has vanished, small
white bubbles are seen to be resting
on the tubes, resembling pearls
not only in shape, but also in colour. After
a short time the
again raised six or eight small white bubbles, it is poured off and the
tubes are
taken out and washed four or five times with spring water; or
if they are
heated with the same water, when it is boiling, they will
shine more brilliantly. Then they are placed in a saucer, which is held in the hand and gradually
dried by the gentle heat of the fire; afterward the saucer is placed
over glowing
charcoal and covered with a charcoal, and a moderate blast
is blown upon it In the end the tubes
are weighed, and if their weights prove equal, he
who has undertaken this work
has not laboured in vain. Lastly, both are placed in another balance-pan and
weighed; of each tube
four grains must not be counted, on account of the
silver which remains
in the gold and cannot be separated from it. From the
weight of the tubes we learn the weight both of the gold and of
the silver
which is in the button. If some assayer has omitted to add so much silver to
the gold as to make
it three times the quantity, but only double, or two and a
half times
as much, he will require the stronger quality of
separates gold from silver,
such as the fourth quality. Whether the
which he
employs for gold and silver is suitable for the purpose, or whether
it
is more or less strong than is right, is recognised by its effect. That of
medium strength raises the little bubbles on the tubes and is
found to colour
the ampulla and the operculum a strong red; the weaker
one is found to
colour them a light red, and the stronger one to break
the tubes. To pure
silver in which there is some portion of gold, nothing should be
added when
they are being heated in the cupel prior to their being
parted, except a
of
lead and one-fourth or one-third its amount of copper of the lesser weights.
If the silver contains in itself a certain amount of copper, let it be
weighed,
both after it has been melted with the lead, and after the
gold has been parted
from it; by the former we learn how much copper is
in it, by the latter how
much gold. Base metals are burnt up even to-day for the purpose of assay,
because
to lose so little of the metal is small loss, but from a large mass of
base metal, the precious metal is always extracted, as I will explain
in
Books X. and XI.
We assay an alloy of copper and silver in the following way.
From a
few cakes of copper the assayer cuts out portions, small samples
from small
cakes, medium samples from medium cakes, and large samples
from large
cakes; the small ones are equal in size to half a hazel nut,
the large
ones do not exceed the size of half a chestnut, and those of
medium size come
between the two. He cuts out the samples from the middle of the
bottom of each cake. He places the samples in a new, clean, triangular
crucible and fixes to
them pieces of paper upon which are written the weight
of the cakes of
copper, of whatever size they may be; for example, he writes,
“These samples have been cut from copper which weighs twenty
pondía.”
copper of this kind has in it, first of all he throws glowing coals
into the
iron hoop, then adds charcoal to it. When the fire has become hot, the paper
is taken out of the crucible and
put aside, he then sets that crucible on the
fire and gradually heats
it for a quarter of an hour until it becomes red hot. Then he stimulates the fire by blowing with a blast from the double bellows
for half an hour, because copper which is devoid of lead requires this
time to
become hot and to melt; copper not devoid of lead melts
quicker. When
he has blown the bellows for about the space of time stated, he
removes the
glowing charcoal with the tongs, and stirs the copper with
a splinter of wood,
which he grasps with the tongs. If it does not stir easily, it is a sign that the
large piece of charcoal in the crucible, and replaces the glowing
charcoal which
had been removed, and again blows the bellows for a
short time. When all
the copper has melted he stops using the bellows, for if he
were to continue
to use them, the fire would consume part of the
copper, and then that which
remained would be richer than the cake from
which it had been cut; this is
no small mistake. Therefore, as soon as the copper has become sufficiently
liquified, he
pours it out into a little iron mould, which may be large or small,
according as more or less copper is melted in the crucible for the
purpose of the
assay. The mould has a handle, likewise made of iron, by which it is held
when
the copper is poured in, after which, he plunges it into a tub of water
placed near at hand, that the copper may be cooled. Then he again dries the
copper by the fire, and cuts off its point with
an iron wedge; the portion
nearest the point he hammers on an anvil and
makes into a leaf, which he
cuts into pieces.
A—IRON MOULD. B—ITS HANDLE.
Others stir the molten copper with a stick of linden tree charcoal, and
then pour it over a bundle of new clean birch twigs, beneath which is
placed
a wooden tub of sufficient size and full of water, and in this
manner the copper
is broken up into little granules as small as hemp
seeds. Others employ straw
in place of twigs. Others place a broad stone in a tub and pour in enough
water to cover
the stone, then they run out the molten copper from the
crucible on to
the stone, from which the minute granules roll off; others
pour the
molten copper into water and stir it until it is resolved into granules.
The fire does not easily melt the copper in the cupel unless it has been
poured
and a thin leaf made of it, or unless it has been resolved into
granules or
made into filings; and if it does not melt, all the labour
has been undertaken
in vain. In order that they may be accurately weighed out, silver and lead
are
resolved into granules in the same manner as copper. But to return
to the assay of copper. When the copper has been prepared by these
methods, if it is free of
lead and iron, and rich in silver, to each
díum
however, the copper
contains some lead, add one
iron, add two First put the lead into a cupel, and after it begins
to smoke, add the
copper; the fire generally consumes the copper, together
with the lead,
in about one hour and a quarter. When this is done, the silver
The fire consumes both of those
metals more quickly if they are heated
in that furnace which draws in air. It
is better to cover the upper half of it with a lid, and not only to
put on the
muffle door, but also to close the window of the muffle door
with a piece of
charcoal, or with a piece of brick. If the copper be such that the silver can
only be separated from it with
difficulty, then before it is tested with fire in
the cupel, lead
should first be put into the scorifier, and then the copper should
be
added with a moderate quantity of melted salt, both that the lead may
absorb the copper and that the copper may be cleansed of the dross
which
abounds in it.
Tin which contains silver should not at the beginning of the assay be
placed in a cupel, lest the silver, as often happens, be consumed and
converted
into fumes, together with the tin. As soon as the lead
in the scorifier, then add thatIn this way the lead will take the
silver and the tin will boil and turn
into ashes, which may be removed with a
wooden splinter. The same thing occurs if any alloy is melted in which there
is tin. When the lead has absorbed the silver which was in the tin, then,
and
not till then, it is heated in the cupel. First place the lead with which
the silver is mixed, in an iron pan, and
stand it on a hot furnace and let it
melt; afterward pour this lead
into a small iron mould, and then beat it
out with a hammer on an anvil
and make it into leaves in the same way as
the copper. Lastly, place it in the cupel, which assay can be carried out in
the
space of half an hour. A great heat is harmful to it, for which reason
there is no necessity
either to cover the half of the furnace with a lid or to
close up its
mouth.
The minted metal alloys, which are known as money, are assayed in the
following way. The smaller silver coins which have been picked out from
the bottom and
top and sides of a heap are first carefully cleansed; then, after
they
have been melted in the triangular crucible, they are either resolved
into granules, or made into thin leaves. As for the large coins which weigh
a Then take a
take another
Wrap each sample separately in paper,
and afterwards place two small
pieces of lead in two cupels which have first
been heated. The more precious the money is, the smaller portion of lead
do we
require for the assay, the more base, the larger is the portion required;
for if a
we add to the If it is composed of equal
parts of silver and copper, we add an
there is only half an
of lead. As soon as the lead has begun to fume, put into each cupel one of
the
papers in which is wrapped the sample of silver alloyed with copper, and
close the mouth of the muffle with charcoal. Heat them with a gentle fire
until all the lead and copper are consumed,
for a hot fire by its heat forces the
the assay is rendered erroneous. Then take the beads out of the cupel and
clean them of dross. If neither depresses the pan of the balance in which it
is placed, but
their weight is equal, the assay has been free from error; but
if one
bead depresses its pan, then there is an error, for which reason the
assay must be repeated. If the
pure silver it is because the King, or Prince, or the State who coins
the money,
has taken one
expense of coining, he having added copper to the silver. Of all these
matters I have written extensively in my book
Monetís.
We assay gold coins in various ways.
If there is copper mixed with
the gold, we melt them by fire in the same
way as silver coins; if there is
silver mixed with the gold, they are
separated by the strongest
if there is copper and silver mixed with the gold,
then in the first place, after
the addition of lead, they are heated in
the cupel until the fire consumes the
copper and the lead, and
afterward the gold is parted from the silver.
It remains to speak of the touchstone
tested, and which was also used by
the Ancients. For although the assay made
by fire is more certain, still, since we
often have no furnace, nor muffle, nor
crucibles, or some delay must be
occasioned in using them, we can always
rub gold or silver on the
touchstone, which we can have in readiness. Further, when gold coins are assayed in the fire, of what use are they
after
ward? A touchstone must be selected which is thoroughly black and free
of
sulphur, for the blacker it is and the more devoid of sulphur, the better it
First the gold is
rubbed on the touchstone, whether it contains silver
or whether it is obtained
from the mines or from the smelting; silver
also is rubbed in the same
way. Then one of the needles, that we judge by its colour to be of similar
composition, is rubbed on the touchstone; if this proves too pale,
another
needle which has a stronger colour is rubbed on the touchstone;
and if this
proves too deep in colour, a third which has a little paler
colour is used. For
this will show us how great a proportion of silver or copper, or
silver and
copper together, is in the gold, or else how great a
proportion of copper is in
silver.
These needles are of four kinds.
silver, the second of gold and
copper, the third of gold, silver, and copper,
and the fourth of silver
and copper. The first three kinds of needles are
used principally for testing gold,
and the fourth for silver. Needles of this
kind are prepared in the following ways. The lesser weights correspond
proportionately to the larger weights, and
both of them are used, not
only by mining people, but by coiners also. The needles are made in
accordance with the lesser weights, and each set
corresponds to a
which, in our own vocabulary, is called a The
by those who coin gold, is divided into twenty-four double
divided into
four
is divided into three units of four
a If we made the needles to be each four
two
hundred and eighty-eight in a
or a double By these two
methods too many needles would be made, and the majority
of them, by reason
of the small difference in the proportion of the
gold, would indicate nothing,
therefore it is advisable to make them
each of a double
twenty-four needles are made, of which the first is made of
twenty-three Fannius is our authority that the Ancients
called the double When a bar of silver is rubbed on the
touchstone and colours it just as
this needle does, it contains one In this manner we determine by the other needles what proportion of gold
there is, or when the gold exceeds the silver in weight, what
proportion of
silver.
The needles are made
The 1st needle of 23
The 2nd needle of 22
The 3rd needle of 21
The 4th needle of 20
The 5th needle of 19
The 6th needle of 18
The 7th needle of 17
The 8th needle of 16
The 9th needle of 15
The 10th needle of 14
The 11th needle of 13
The 12th needle of 12
The 13th needle of 11
The 14th needle of 10
The 15th needle of 9
The 16th needle of 8
The 17th needle of 7
The 18th needle of 6
The 19th needle of 5
The 20th needle of 4
The 21st needle of 3
The 22nd needle of 2
The 23rd needle of 1
The 24th needle of pure gold
By the first eleven needles, when they are rubbed on the touchstone, we
test what proportion of gold a bar of silver contains, and with the
remaining
thirteen we test what proportion of silver is in a bar of
gold; and also what
proportion of either may be in money.
Since some gold coins are composed of gold and copper, thirteen needles
of another kind are made as follows:—
The 1st of 12
The 2nd of 13
The 3rd of 14
The 4th of 15
The 5th of 16
The 6th of 17
The 7th of 18
The 8th of 19
The 9th of 20
The 10th of 21
The 11th of 22
The 12th of 23
The 13th of pure gold.
These needles are not much used, because gold coins of that kind are
somewhat rare; the ones chiefly used are those in which there is much
copper. Needles of the third kind, which are composed of gold, silver, and
copper, are more largely used, because such gold coins are common. But since
with the gold there are mixed equal or unequal portions of
silver and copper,
two sorts of needles are made. If the proportion of silver and copper is
equal, the needles are as
follows:—
Some make twenty-five needles, in order to be able to detect the two
Of these needles, the
first is composed of twelve
number of copper. The second, of twelve
five The remaining needles are
made in the same proportion.
Pliny is our authority that the Romans could tell to within one
how much
gold was in any given alloy, and how much silver or copper.
Needles may be made in either of two ways, namely, in the ways of which
I have spoken, and in the ways of which I am now about to speak. If
seven needles are made in the following
way:—
Since it is rarely found that gold, which has been coined, does not amount to
at least fifteen
some make them different from those
already described, inasmuch as the
alloy of gold with silver and copper
is sometimes differently proportioned.
These needles are made:—
Next follows the fourth kind of needles, by which we test silver coins
which contain copper, or copper coins which contain silver. The
which we
weigh the silver is divided in two different ways. It is either
divided twelve times, into units of five
into twenty-four
units of four
call a
are
called Or else the
sixteen
each Needles are made in accordance with
each method of dividing the According to the first method, to the
number of twenty-four half
number of thirty-one half
needles were made to the number of the smaller weights,
the number of
needles would again be too large, and not a few of them,
by reason of the
small difference in proportion of silver or copper,
would have no significance. We test both bars and coined money composed of silver and copper by both
scales. The one is as follows: the first needle is made of twenty-three
parts of
copper and one part silver; whereby, whatsoever bar or coin, when
rubbed on the touchstone, colours it just as this needle does, in that
bar or
money there is one twenty-fourth part of silver, and so also, in
accordance
with the proportion of silver, is known the remaining
proportion of the copper.
The 1st needle is made of 23 parts of copper and 1 of silver.
The 2nd needle is made of 22 parts of copper and 2 of silver.
The 3rd needle is made of 21 parts of copper and 3 of silver.
The 4th needle is made of 20 parts of copper and 4 of silver.
The 5th needle is made of 19 parts of copper and 5 of silver.
The 6th needle is made of 18 parts of copper and 6 of silver.
The 7th needle is made of 17 parts of copper and 7 of silver.
The 8th needle is made of 16 parts of copper and 8 of silver.
The 9th needle is made of 15 parts of copper and 9 of silver.
The 10th needle is made of 14 parts of copper and 10 of silver.
The 11th needle is made of 13 parts of copper and 11 of silver.
The 12th needle is made of 12 parts of copper and 12 of silver.
The 13th needle is made of 11 parts of copper and 13 of silver.
The 14th needle is made of 10 parts of copper and 14 of silver.
The 15th needle is made of 9 parts of copper and 15 of silver.
The 16th needle is made of 8 parts of copper and 16 of silver.
The 17th needle is made of 7 parts of copper and 17 of silver.
The 18th needle is made of 6 parts of copper and 18 of silver.
The 19th needle is made of 5 parts of copper and 19 of silver.
The 20th needle is made of 4 parts of copper and 20 of silver.
The 21st needle is made of 3 parts of copper and 21 of silver.
The 22nd needle is made of 2 parts of copper and 22 of silver.
The 23rd needle is made of 1 parts of copper and 23 of silver.
The 24th of pure silver.
The other method of making needles is as follows:—
So much for this.
Perhaps I have used more words than those most
highly skilled in the art
may require, but it is necessary for the understanding
of these
matters.
I will now speak of the weights, of which I have frequently made mention.
Among mining people these are of two kinds, that is, the greater weights and
the lesser weights. The
hundred weight.
The various weights are:—
1st = 100
2nd = 50
3rd = 52
4th = 16
5th = 8
6th = 4
7th = 2
8th = 1
This
the
they divide it, of sixteen
9th = 8
10th = 8
11th = 4
12th = 2
13th = 1
14th = 1
15th = 1
16th = 1
The above is how the “greater” weights are divided.
The “lesser”
weights are made of silver or brass or copper. Of these, the first and largest
generally weighs one
ore, but also metals to be assayed, and
smaller quantities of lead. The first
of these weights is called a
corresponds
to the larger scale, being likewise one hundred
The 1st is called 1
The 2nd is called 50
The 3rd is called 25
The 4th is called 16
The 5th is called 8
The 6th is called 4
The 7th is called 2
The 8th is called 1
The 9th is called 1
The 10th is called 8
The 11th is called 4
The 12th is called 2
The 13th is called 1
The 14th is called 1
The fourteenth is the last, for the proportionate weights which correspond
with a On all these weights of
the lesser scale, are written the numbers of
Some
of a different scale. Their largest weight of the greater scale weighs one
hundred and twelve
1st = 112
2nd = 64
3rd = 32
4th = 16
5th = 8
6th = 4
7th = 2
8th = 1
9th = 1
10th = 8
11th = 4
12th = 2
13th = 1
As for the
said, call a
just like the greater weights scale, into twenty-four
units of two
each, and each unit of two
each Some also divide
the separate units of four
omitting the
four Thus
the first and greatest unit of measurement, which is the
four double
The 2nd = 12 double
The 3rd = 6 double
The 4th = 3 double
The 5th = 2 double
The 6th = 1 double
The 7th = 2
The 8th = 1
The 9th = 2 units of four
The 10th = 1 units of four
Coiners who mint silver also divide the
way as the
greater weights; our people, indeed, divide it into sixteen
uncíae,
There are ten weights which are placed in the other pan of the balance,
when they weigh the silver which remains from the copper that has been
consumed, when they assay the alloy with fire.
The 1st = 16
The 2nd = 8
The 3rd = 4
The 4th = 2
The 5th = 1
The 6th = 9 units of 4
The 7th = 6 units of 4
The 8th = 3 units of 4
The 9th = 2 units of 4
The 10th = 1 units of 4
The coiners of Nuremberg who mint silver, divide the
uncíae,
four They employ nine weights.
The 1st = 16
The 2nd = 8
The 3rd = 4
The 4th = 2
The 5th = 1
For they divide the
divide the
the 6th weight = 2
the 7th weight = 1
the 8th weight = 2
the 9th weight = 1
The men of Cologne and Antwerp
five Each
of these they again divide into twenty-four units of four
which they
call They have ten weights, of which
the 1st = 12
the 2nd = 6
the 3rd = 3
the 4th = 2
the 5th = 1
the 6th = 12 units of 4
the 7th = 6 units of 4
the 8th = 3 units of 4
the 9th = 2 units of 4
the 10th = 1 units of 4
And so with them, just as with our own people, the
two hundred and
eighty-eight
divided into two hundred and
fifty-six Lastly, the Venetians divide
the The
thirty-six
They make twelve weights, which they use whenever they
wish to assay
alloys of silver and copper. Of these
the 1st = 8
the 2nd = 4
the 3rd = 2
the 4th = 1
the 5th = 2
the 6th = 1
the 7th = 18
the 8th = 9
the 9th = 6
the 10th = 3
the 11th = 2
the 12th = 1
Since the Venetians divide the
or two hundred and
eighty-eight units of 4
our people also divide the
and both agree, even though the Venetians divide the
divisions.
This, then, is the system of weights, both of the greater and the lesser
kinds,
which metallurgists employ, and likewise the system of the
lesser weights
which coiners and merchants employ, when they are
assaying metals and
coined money. The
selves when they weigh large masses of
these things, I have explained in my
work
et Monetis.
There are three small balances by which we weigh ore, metals, and
fluxes. The first, by which we weigh lead and fluxes, is the largest among these
smaller balances, and when eight
one of its
pans, and the same number in the other, it sustains no damage. The second is more delicate, and by this we weigh the ore or the metal, which
is to be assayed; this is well able to carry one The third is the most delicate, and by this we weigh the beads of gold or
silver, which, when the assay is completed, settle in the bottom of the
cupel. But if anyone weighs lead in the second balance, or an ore in the third, he
will do them much injury.
Whatsoever small amount of metal is obtained from a
of the lesser weights of
ore or metal alloy, the same greater weight of metal
is smelted from a
A—FIRST SMALL BALANCE. B—SECOND. C—THIRD, PLACED IN A
CASE.
END OF BOOK VII.
Questions of assaying were explained in the last
Book, and I have now
come to a greater task, that
is, to the description of how we extract
the metals. First of all I will explain the method of preparing
the ore
in an impure state, mixed with earth, stones, and
solidified juices, it is necessary to separate most of
these
impurities from the ores as far as can be,
before they are smelted, and
therefore I will now
describe the methods by which the ores are sorted,
broken with hammers,
burnt, crushed with stamps, ground into powder,
sifted, washed, roasted,
and calcined
A—LONG TABLE. B—TRAY. C—TUB.
I will start at the beginning with the first sort of work.
Experienced
miners, when they dig the ore, sort the metalliferous
material from earth,
stones, and solidified juices before it is taken
from the shafts and tunnels,
and they put the valuable metal in trays
and the waste into buckets. But
if some miner who is inexperienced in mining matters has omitted to
do this,
or even if some experienced miner, compelled by some
unavoidable necessity,
has been unable to do so, as soon as the
material which has been dug out
has been removed from the mine, all of
it should be examined, and that part of
the ore which is rich in metal
sorted from that part of it which is devoid of
metal, whether such part
be earth, or solidified juices, or stones. To smelt
waste together with an ore involves a loss, for some
expenditure is thrown
away, seeing that out of earth and stones only
empty and useless slags are
metals and cause
loss. The rock which lies contiguous to rich ore should also be
broken into
small pieces, crushed, and washed, lest any of the mineral should
be
lost. When, either through ignorance or carelessness, the miners while
excavating have mixed the ore with earth or broken rock, the work of
sorting
the crude metal or the best ore is done not only by men, but
also by boys and
women. They throw the mixed material upon a long table, beside which they
sìt for almost the whole day, and they sort out the ore; when it
has been
sorted out, they collect it in trays, and when collected they
throw it into
tubs, which are carried to the works in which the ores
are smelted.
The metal which is dug out in a pure or crude state, to which class belong
native silver, silver glance, and gray silver, is placed on a stone by
the
mine foreman and flattened out by pounding with heavy square
hammers. These masses, when they have been thus flattened out like plates, are placed
either on the stump of a tree, and cut into pieces by pounding an iron
chisel
into them with a hammer, or else they are cut with an iron tool
similar to a
pair of shears. One blade of these shears is three feet long, and is firmly
fixed in a
stump, and the other blade which cuts the metal is six feet long.
A—MASSES OF METAL. B—HAMMER. C—CHISEL. D—TREE STUMPS.
E—IRON TOOL
SIMILAR TO A PAIR OF SHEARS.
cupellation furnace by the smelters.
Although the miners, in the shafts or tunnels, have sorted over the
material which they mine, still the ore which has been broken down and
carried
out must be broken into pieces by a hammer or minutely crushed,
so that
the more valuable and better parts can be distinguished from
the inferior and
worthless portions. This is of the greatest importance in smelting ore, for
if the ore is
smelted without this separation, the valuable part frequently
receives
great damage before the worthless part melts in the fire, or else the
one consumes the other; this latter difficulty can, however, be partly
avoided by the exercise of care and partly by the use of fluxes. Now, if a
vein is of poor quality, the better portions which have been
broken down and
carried out should be thrown together in one place, and
the inferior portion
and the rock thrown away. The sorters place a hard broad stone on a table;
the tables are
generally four feet square and made of joined planks, and to
the edge
of the sides and back are fixed upright planks, which rise about a
foot
from the table; the front, where the sorter sits, is left open. The
A—TABLES. B—UPRIGHT PLANKS. C—HAMMER. D—QUADRANGULAR
HAMMER.
E—DEEPER VESSEL. F—SHALLOWER VESSEL. G—IRON
ROD.
broken up with a broad, but not thick,
hammer; they either break them into
pieces and throw them into one
vessel, or they break and sort—whence they
get their
name—the more precious from the worthless, throwing and collecting
them separately into different vessels. Other men crush the lumps of ore
less rich in gold or silver, which have
likewise been put on the stone, with a
broad thick hammer, and when it
has been well crushed, they collect it and
throw it into one vessel. There are two kinds of vessels; one is deeper, and a
little wider in the
centre than at the top or bottom; the other is not so deep
though it is
broader at the bottom, and becomes gradually a little narrower
toward
the top. The latter vessel is covered with a lid, while the former is not
covered; an iron rod through the handles, bent over on either end, is
grasped in the hand when the vessel is carried. But, above all, it behooves
the sorters to be assiduous in their
labours.
By another method of breaking ore with hammers, large hard
frag
ments of ore are broken before they are burned. The legs of the workmen
—at all events of those who crush pyrites
in this manner with large hammers
in Goslar—are protected with
coverings resembling leggings, and their hands
A—PYRITES. B—LEGGINGS. C—GLOVES. D—HAMMER.
chips which fly away from the fragments.
In that district of Greater Germany which is called Westphalia and in
that district of Lower Germany which is named Eifel, the broken ore
which
has been burned, is thrown by the workmen into a round area paved
with the
hardest stones, and the fragments are pounded up with iron
tools, which are
very much like hammers in shape and are used like
threshing sledges. This
tool is a foot long, a palm wide, and a digit thick, and has an
opening in the
middle just as hammers have, in which is fixed a wooden
handle of no great
thickness, but up to three and a half feet long, in
order that the workmen
can pound the ore with greater force by reason
of its weight falling from a
greater height. They strike and pound with the broad side of the tool, in the
same way
as corn is pounded out on a threshing floor with the threshing
sledges,
although the latter are made of wood and are smooth and fixed to
poles. When the ore has been broken into small pieces, they sweep it
together
with brooms and remove it to the works, where it is washed
A—AREA PAVED WITH STONES. B—BROKEN ORE. C—AREA COVERED WITH
BROKEN ORE.
D—IRON TOOL. E—ITS HANDLE. F—BROOM.
G—SHORT STRAKE. H—WOODEN HOE.
upward with a wooden hoe. The water running down again, carries all
the light particles into a
trough placed underneath. I shall deal more fully
with this method of washing a little later.
Ore is burned for two reasons; either that from being hard, it may become
soft and more easily broken and more readily crushed with a hammer or
stamps, and then can be smelted; or that the fatty things, that is to
say,
sulphur, bitumen, orpiment, or realgarSulphur is
frequently found in metallic ores, and, generally speaking,
is more harmful
to the metals, except gold, than are the other things. It is most harmful of
all to iron, and less to tin than to bismuth,
lead, silver, or copper. Since very rarely gold is found in which there is not some silver, even gold
ores containing sulphur ought to be roasted before they are smelted,
because,
in a very vigorous furnace fire, sulphur resolves metal into
ashes and makes
slag of it. Bitumen acts in the same way, in fact sometimes it consumes
silver,
which we may see in bituminous
I now come to the methods of roasting, and first of all to that one which
is common to all ores. The earth is dug out to the required extent, and
thus is made a
quadrangular area of fair size, open at the front, and above
this,
firewood is laid close together, and on it other wood is laid
trans
versely, likewise close together, for which reason our
countrymen call this
pile of wood a crate; this is repeated until the
pile attains a height of one
or two cubits. Then there is placed upon it a quantity of ore that has been
broken into
small pieces with a hammer; first the largest of these pieces,
next
those of medium size, and lastly the smallest, and thus is built up a
gently sloping cone. To prevent it from becoming scattered, fine sand of the
A—AREA. B—WOOD. C—ORE. D—CONE-SHAPED PILES.
E—CANAL.
same ore is soaked with water and smeared over it and
beaten on with shovels;
some workers, if they cannot obtain such fine
sand, cover the pile with char
coal-dust, just as do
charcoal-burners. But at Goslar, the pile, when it has
been built up in the form of a
cone, is smeared with
rubrumIn some districts the ore is roasted once, in others twice, in others three
times,
as its hardness may require. At Goslar, when pyrites is roasted for the third
time, that which is
placed on the top of the pyre exudes a certain greenish,
dry, rough,
thin substance, as I have elsewhere written
easily burned by the fire than is
asbestos. Very often also, water is put on
it softer and
more easily broken; for after fire has dried up the moisture
in the
ore, it breaks up more easily while it is still hot, of which fact burnt
limestone affords the best example.
By digging out the earth they make the areas much larger, and square;
walls should be built along the sides and back to hold the heat of the
fire more effectively, and the front should be left open. In these compart
ments tin ore is roasted in the following manner. First of all wood about
twelve feet long should be laid in the area in
four layers, alternately straight
and transverse. Then the larger pieces of ore should be laid upon them, and
on these
again the smaller ones, which should also be placed around the sides;
the fine sand of the same ore should also be spread over the pile and
pounded
with shovels, to prevent the pile from falling before it has
been roasted; the
wood should then be fired.
A—LIGHTED PYRE. B—PYRE WHICH IS BEING CONSTRUCTED. C—ORE.
D—WOOD.
E—PILE OF THE SAME WOOD.
Lead ore, if roasting is necessary, should be piled in an area just like the
last, but sloping, and the wood should be placed over it. A tree trunk should
be laid right across the front of the ore to prevent
it from falling out. The
ore, being roasted in this way, becomes partly melted and resembles
slag.
particle of vitriol has been
obtained by heating it in water, is thrown into a
furnace, in which
logs are placed. This furnace is very similar to an oven
in shape, in order that when the
ore is roasted the valuable contents may not
fly away with the smoke,
but may adhere to the roof of the furnace. In this
way sulphur very often hangs like icicles from the two openings
of the roof
through which the smoke escapes.
A—BURNING PYRE WHICH IS COMPOSED OF LEAD ORE WITH WOOD PLACED ABOVE IT.
B—WORKMAN THROWING ORE INTO ANOTHER AREA. C—OVEN-SHAPED
FURNACE.
D—OPENINGS THROUGH WHICH THE SMOKE ESCAPES.
If pyrites or
deal of sulphur or
bitumen, it should be so roasted that neither is lost. For
this purpose it is thrown on an iron plate full of holes, and
roasted with char
coal placed on top; three walls support this
plate, two on the sides and the
third at the back. Beneath the plate are placed pots containing water, into
which the
sulphurous or bituminous vapour descends, and in the water the
fat
accumulates and floats on the top. If it is sulphur, it is generally of a
yellow colour; if bitumen, it is
black like pitch. If these were not drawn
out they would do much harm to the metal, when
the ore is being smelted. When they have thus been separated they prove of some service to man,
especially the sulphurous kind. From the vapour which is carried down, not
A—IRON PLATES FULL OF HOLES. B—WALLS. C—PLATE ON WHICH ORE
IS PLACED.
D—BURNING CHARCOAL PLACED ON THE ORE. E—POTS.
F—FURNACE. G—MIDDLE
PART OF UPPER CHAMBER. H—THE
OTHER TWO COMPARTMENTS. I—DIVISIONS OF THE
LOWER CHAMBER.
K—MIDDLE WALL. L—POTS WHICH ARE FILLED WITH ORE. M—LIDS
OF SAME POTS. N—GRATING.
bituminous
substance resembling
blown away with a breath. Some employ a vaulted furnace, open at the
front and divided into two
chambers. A wall built in the middle of the
furnace divides the lower chamber into
two equal parts, in which are set pots
containing water, as above
described. The upper chamber is again divided
into three parts, the middle one of
which is always open, for in it the wood
is placed, and it is not
broader than the middle wall, of which it forms the
topmost portion. The other two compartments have iron doors which are
closed, and which,
together with the roof, keep in the heat when the wood
is lighted. In these upper compartments are iron bars which take the place
of a
floor, and on these are arranged pots without bottoms, having in
place
of a bottom, a grating made of iron wire, fixed to each, through
the
openings of which the sulphurous or bituminous vapours roasted from
the
ore run into the lower pots. Each of the upper pots holds a hundred
A—HEAP OF CUPRIFEROUS STONES. B—KINDLED HEAP. C—STONES
BEING TAKEN TO
THE BEDS OF FAGGOTS.
with
lute.
In Eisleben and the neighbourhood, when they roast the schistose
stone
from which copper is smelted, and which is not free from bitumen,
they
do not use piles of logs, but bundles of faggots. At one time, they used
to pile this kind of stone, when extracted from
the pit, on bundles of
faggots and roast it by firing the faggots;
nowadays, they first of all
carry these same stones to a heap, where
they are left to lie for some time in
such a way as to allow the air
and rain to soften them. Then they make a
bed of faggot bundles near the heap, and carry the
nearest stones to this
bed; afterward they again place bundles of
faggots in the empty place
from which the first stones have been
removed, and pile over this extended
bed, the stones which lay nearest
to the first lot; and they do this right up to
the end, until all the
stones have been piled mound-shape on a bed of faggots. Finally they fire the faggots, not, however, on the side where the wind is
blowing, but on the opposite side, lest the fire blown up by the force
of the
wind should consume the faggots before the stones are roasted
and made soft;
by this method the stones which are adjacent to the
faggots take fire and
communicate it to the next ones, and these again
to the adjoining ones, and
in this way the heap very often burns
continuously for thirty days or more. This schist rock when rich in copper, as I have said elsewhere, exudes a
substance of a nature similar to asbestos.
Ore is crushed with iron-shod stamps, in order that the metal may be
separated from the stone and the hanging-wall rock.
miners use for this
purpose are of four kinds, and are made by the following
method. A block of oak timber six feet long, two feet and a palm square, is
laid
on the ground. In the middle of this is fixed a mortar-box, two feet and six
digits
long, one foot and six digits deep; the front, which might be called a
and two palms and as many digits wide, each end of
which is wedged into the
timber with broad wedges, and the front and
back part of it are fixed to the
timber with iron nails. To the sides of the mortar above the block are fixed
two upright posts,
whose upper ends are somewhat cut back and are mor
tised to the
timbers of the building. Two and a half feet above the mortar
the ends
of which are mortised into the upright posts already mentioned. Through each mortise is bored a hole, into which is driven an iron
clavis
one end of the clavis has two horns, and the other end is
perforated in order
that a wedge driven through, binds the beams more
firmly; one horn of the
clavis turns up and the other down. Three and a half feet above the cross-
manner;
these cross-beams have square openings, in which the iron-shod
stamps
are inserted. The stamps are not far distant from each other, and
fit closely in the
cross-beams. Each stamp has a tappet at the back, which
requires to be daubed with
grease on the lower side that it can be raised
more easily. For each stamp there are on a cam-shaft, two cams, rounded on
into the mortar, it may with its iron head
pound and crush the rock which
has been thrown under it. To the cam-shaft is fixed a water-wheel whose
buckets are turned by
water-power. Instead of doors, the mouth of the
mortar has a board, which is fitted
into notches cut out of the front of the block. This board can be raised, in order that when the mouth is open, the workmen
A—MORTAR. B—UPRIGHT POSTS. C—CROSS-BEAMS. D—STAMPS.
E—THEIR HEADS.
F—AXLE (CAM-SHAFT). G—TOOTH OF THE
STAMP (TAPPET). H—TEETH OF AXLE (CAMS).
can remove with a shovel
the fine sand, and likewise the coarse sand and
broken rock, into which
the rocks have been crushed; this board can be
lowered, so that the
mouth thus being closed, the fresh rock thrown in may
be crushed with
the iron-shod stamps. If an oak block is not available,
two timbers are placed on the ground
and joined together with iron clamps,
each of the timbers being six
feet long, a foot wide, and a foot and a half thick. Such depth as should be allowed to the mortar, is obtained by cutting out the
first beam to a width of three-quarters of a foot and to a length of
two and a
third and one twenty-fourth of a foot. In the bottom of the part thus dug
out, there should be laid a very hard
rock, a foot thick and three-quarters of a
foot wide; about it, if any
space remains, earth or sand should be filled in
and pounded. On the front, this bed rock is covered with a plank; this
rock when it
has been broken, should be taken away and replaced by
another. A smaller mortar having room for only three stamps may also be
made in
the same manner.
The stamp-stems are made of small square timbers nine feet long and
half
a foot wide each way. The iron head of each is made in the following
same
length. The lower part is a palm square in the middle for two palms,
then below
this, for a length of two digits it gradually spreads until it
becomes
five digits square; above the middle part, for a length of two
digits,
it again gradually swells out until it becomes a palm and a half square.
Higher up, where the head of the shoe is enclosed in the stem, it is bored
through and similarly the stem itself is pierced, and through the
opening of
each, there passes a broad iron wedge, which prevents the
head falling off the
stem. To prevent the stamp head from becoming broken by the constant
striking
of fragments of ore or rocks, there is placed around it a quadrangular
iron band a digit thick, seven digits wide, and six digits deep. Those who
use three stamps, as is common, make them much larger, and
they are
made square and three palms broad each way; then the iron shoe
of each has a total length of two feet and a palm; at the lower end, it
is
hexagonal, and at that point it is seven digits wide and thick. The lower
part of it which projects beyond the stem is one foot and two
palms long;
the upper part, which is enclosed in the stem, is three
palms long; the
A—STAMP. B—STEM CUT OUT IN LOWER PART. C—SHOE. D—THE
OTHER SHOE,
BARBED AND GROOVED. E—QUADRANGULAR IRON BAND.
F—WEDGE. G—TAPPET.
H—ANGULAR CAM-SHAFT. I—CAMS.
K—PAIR OF COMPASSES.
narrower and thinner, so
that at the top it is three digits and a half wide and
two thick. It is bored through at the place where the angles have been
somewhat cut
away; the hole is three digits long and one wide, and is one
digit's
distance from the top. There are some who make that part of the
head which is enclosed in the
stem, barbed and grooved, in order that when
the hooks have been fixed
into the stem and wedges fitted to the grooves,
it may remain tightly
fixed, especially when it is also held with two quad
rangular iron
bands. Some divide the cam-shaft with a compass into six
sides, others into
nine; it is better for it to be divided into twelve sides, in
order
that successively one side may contain a cam and the next be without
one.
The water-wheel is entirely enclosed under a quadrangular box, in case
either the deep snows or ice in winter, or storms, may impede its
running and
its turning around. The joints in the planks are stopped all around with
moss. The cover, however, has one opening, through which there passes
a race
bringing down water which, dropping on the buckets of the wheel,
turns
it round, and flows out again in the lower race under the box. The
spokes of the water-wheel are not infrequently mortised into the
middle of
A—BOX. ALTHOUGH THE UPPER PART IS NOT OPEN, IT IS SHOWN OPEN HERE, THAT
THE
WHEEL MAY BE SEEN. B—WHEEL. C—CAM-SHAFT.
D—STAMPS.
either both crush dry or wet ore,
or else the one set crushes dry ore and the
other set wet ore, just as
circumstances require the one or the other;
further, when the one set
is raised and the iron clavises in them are fixed
into openings in the
first cross-beam, the other set alone crushes the ore.
Broken rock or stones, or the coarse or fine sand, are removed from
the
mortar of this machine and heaped up, as is also done with the same
materials when raked out of the dump near the mine. They are thrown
by a workman into a box, which is open on the top and
the front, and is three
feet long and nearly a foot and a half wide. Its sides are sloping and made
of planks, but its bottom is made of iron
wire netting, and fastened with
wire to two iron rods, which are fixed
to the two side planks. This bottom
has openings, through which broken rock of the size of a
hazel nut cannot
pass; the pieces which are too large to pass through
are removed by the
workman, who again places them under stamps, while
those which have
passed through, together with the coarse and fine
sand, he collects in a large
vessel and keeps for the washing. When he is performing his laborious
A—BOX LAID FLAT ON THE GROUND. B—ITS BOTTOM WHICH IS MADE OF IRON
WIRE.
C—BOX INVERTED. D—IRON RODS. E—BOX SUSPENDED
FROM A BEAM, THE INSIDE
BEING VISIBLE. F—BOX SUSPENDED FROM A
BEAM, THE OUTSIDE BEING VISIBLE.This box may rightly
be called a quadrangular sieve, as may also that
kind which follows.
Some employ a sieve shaped like a wooden bucket, bound with two iron
hoops; its bottom, like that of the box, is made of iron wire netting.
They place this on two small cross-planks fixed upon a post set in the
ground.
Some do not fix the post in the ground, but stand it on the ground until
there arises a heap of the material which has passed through the sieve,
and
in this the post is fixed. With an iron shovel the workman throws into this
sieve broken rock,
small stones, coarse and fine sand raked out of the dump;
holding the
handles of the sieve in his hands, he agitates it up and down in
A—SIEVE. B—SMALL PLANKS. C—POST. D—BOTTOM OF SIEVE.
E—OPEN BOX.
F—SMALL CROSS-BEAM. G—UPRIGHT
POSTS.
order that by this movement the dust, fine and coarse sand, small
stones, and
fine broken rock may fall through the bottom. Others do not use a sieve, but
an open box, whose bottom is likewise
covered with wire netting; this they
fix on a small cross-beam fastened
to two upright beams and tilt it backward
and forward.
Some use a sieve made of copper, having square copper handles on both
sides, and through these handles runs a pole, of which one end projects
three
quarters of a foot beyond one handle; the workman then places
that end in
a rope which is suspended from a beam, and rapidly shakes
the pole alter-By this movement the small particles
fall through the bottom of the
sieve. In order that the end of the pole
may be easily placed in the rope, a
stick, two palms long, holds open the
lower part of the rope as it
hangs double, each end of the rope being tied to
the beam; part of the
rope, however, hangs beyond the stick to a length of
half a foot. A large box is also used for this purpose, of which the bottom
is either
made of a plank full of holes or of iron netting, as are the other
boxes. An iron bale is fastened from the middle of the planks which form
its
sides; to this bale is fastened a rope which is suspended from a wooden
beam, in order that the box may be moved or tilted in any direction.
A—BOX. B—BALE. C—ROPE. D—BEAM. E—HANDLES.
F—FIVE-TOOTHED RAKE.
G—SIEVE. H—ITS HANDLES.
I—POLE. K—ROPE. L—TIMBER.
There are two handles on
each end, not unlike the handles of a wheel
barrow; these are held
by two workmen, who shake the box to and fro. This box is the one principally used by the Germans who dwell in the
Carpathian mountains. The smaller particles are separated from the larger
ones by means of
three boxes and two sieves, in order that those which
pass through
each, being of equal size, may be washed together; for the
bottoms of
both the boxes and sieves have openings which do not let
through broken
rock of the size of a hazel nut. As for the dry remnants
under the stamps. The larger pieces of broken rock are not separated from
the smaller by
this method until the men and boys, with five-toothed rakes,
have
separated them from the rock fragments, the little stones, the
coarse
and the fine sand and earth, which have been thrown on to the dumps.
At Neusohl, in the Carpathians, there are mines where the veins of copper
lie in the ridges and peaks of the mountains, and in order to save
expense
being incurred by a long and difficult transport, along a rough
and sometimes
very precipitous road, one workman sorts over the dumps
which have been
thrown out from the mines, and another carries in a
wheelbarrow the earth,
fine and coarse sand, little stones, broken
rock, and even the poorer ore, and
overturns the barrow into a long
open chute fixed to a steep rock. This
chute is held apart by small cleats, and the material slides down a
distance of
about one hundred and fifty feet into a short box, whose
bottom is made of a
thick copper plate, full of holes. This box has two handles by which it is
shaken to and fro, and at the
top there are two bales made of hazel sticks,
in which is fixed the
iron hook of a rope hung from the branch of a tree or
from a wooden
beam which projects from an upright post. From time to
time a sifter pulls this box and thrusts it violently
against the tree or post,
by which means the small particles passing
through its holes descend down
another chute into another short box, in
whose bottom there are smaller
holes. A second sifter, in like manner, thrusts this box violently against a
tree or post, and a second time the smaller particles are received into
a third
chute, and slide down into a third box, whose bottom has still
smaller holes. A third sifter, in like manner, thrusts this box violently against a tree or
post,
and for the third time the tiny particles fall through the holes
upon a table. While the workman is bringing in the barrow, another load which has been
sorted from the dump, each sifter withdraws the hooks from his bale
and carries away his own box and overturns it, heaping up the broken
rock
or sand which remains in the bottom of it. As for the tiny particles which
have slid down upon the table, the first
washer—for there are as many
washers as sifters—sweeps them
off and in a tub nearly full of water, washes
them through a sieve
whose holes are smaller than the holes of the third box. When this tub has been filled with the material which has passed through
the sieve, he draws out the plug to let the water run away; then he
removes
with a shovel that which has settled in the tub and throws it
upon the table
of a second washer, who washes it in a sieve with
smaller holes. The sedi
ment which has this time settled in his tub, he takes out
and throws on the
table of a third washer, who washes it in a sieve
with the smallest holes. The copper concentrates which have settled in the last tub are taken out and
smelted; the sediment which each washer has removed with a limp is
washed on a canvas strake. The sifters at Altenberg, in the tin mines of
the mountains bordering on
Bohemia, use such boxes as I have described,
hung from wooden beams. These, however, are a little larger and open in
the front, through which
opening the broken rock which has not gone through
the sieve can be
shaken out immediately by thrusting the sieve against its post.
A—WORKMAN CARRYING BROKEN ROCK IN A BARROW. B—FIRST CHUTE.
C—FIRST BOX.
D—ITS HANDLES. E—ITS BALES.
F—ROPE. G—BEAM. H—POST. I—SECOND
CHUTE.
K—SECOND BOX. L—THIRD CHUTE. M—THIRD BOX. N—FIRST
TABLE.
O—FIRST SIEVE. P—FIRST TUB. Q—SECOND TABLE.
R—SECOND SIEVE. S—SECOND
TUB. T—THIRD TABLE.
V—THIRD SIEVE. X—THIRD TUB. Y—PLUGS.
If the ore is rich in metal, the earth, the fine and coarse sand, and the
pieces of rock which have been broken from the hanging-wall, are dug
out of
the dump with a spade or rake and, with a shovel, are thrown
into a large sieve
or basket, and washed in a tub nearly full of water. The sieve is generally
a cubit broad and half a foot deep; its bottom
has holes of such size that the
larger pieces of broken rock cannot
pass through them, for this material rests
upon the straight and cross
iron wires, which at their points of contact are
bound by small iron
clips. The sieve is held together by an iron band and by
two cross-rods
likewise of iron; the rest of the sieve is made of staves in the
shape
of a little tub, and is bound with two iron hoops; some, however,
bind
it with hoops of hazel or oak, but in that case they use three of them.
On each side it has handles, which are held in the hands by whoever washes
the metalliferous material. Into this sieve a boy throws the material to be
washed, and a woman
shakes it up and down, turning it alternately to the
A—SIEVE. B—ITS HANDLES. C—TUB. D—BOTTOM OF SIEVE MADE
OF IRON WIRES.
E—HOOP. F—RODS. G—HOOPS. H—WOMAN
SHAKING THE SIEVE. I—BOY SUPPLYING
IT WITH MATERIAL WHICH
REQUIRES WASHING. K—MAN WITH SHOVEL REMOVING FROM
THE TUB THE
MATERIAL WHICH HAS PASSED THROUGH THE SIEVE.
earth, sand, and broken rock. The larger pieces remain in the sieve, and
these are taken out, placed
in a heap and put under the stamps. The
mud, together with fine sand, coarse sand, and broken rock, which
remain
after the water has been drawn out of the tub, is removed by an
iron shovel
and washed in the sluice, about which I will speak a little
later.
The Bohemians use a basket a foot and a half broad and half a foot deep,
bound together by osiers. It has two handles by which it is grasped, when
they move it about and
shake it in the tub or in a small pool nearly full
of water. All that passes through it into the tub or pool they take out and
wash
in a bowl, which is higher in the back part and lower and flat in the
front; it is grasped by the two handles and shaken in the water, the
lighter
particles flowing away, and the heavier and mineral portion
sinking to the
bottom.
A—BASKET. B—ITS HANDLES. C—DISH. D—ITS BACK PART.
E—ITS FRONT PART.
F—HANDLES OF SAME.
Gold ore, after being broken with hammers or crushed by the stamps,
and
even tin ore, is further milled to powder. The upper millstone, which
An axle is rounded
to compass measure, or is made angular, and its iron
pinions turn in iron
sockets which are held in beams. The axle is turned by a water-wheel, the
buckets of which are fixed to
the rim and are struck by the force of a stream.
A—AXLE. B—WATER-WHEEL. C—TOOTHED DRUM. D—DRUM MADE OF
RUNDLES.
E—IRON AXLE. F—MILLSTONE. G—HOPPER.
H—ROUND WOODEN PLATE.
I—TROUGH.
Into the axle is
mortised a toothed drum, whose teeth are fixed in the side
of the rim. These teeth turn a second drum of rundles, which are made of
very hard
material. This drum surrounds an iron axle which has a pinion
at the bottom and
revolves in an iron cup in a timber. At the top of the
iron axle is an iron tongue, dove-tailed into the
millstone, and so when the
teeth of the one drum turn the rundles of
the other, the millstone is made to
turn round. An overhanging machine supplies it with ore through a hopper,
and the
ore, being ground to powder, is discharged from a round wooden plate
into a trough and flowing away through it accumulates on the floor;
from there the ore is carried away and reserved for washing. Since this
lowered, the timber in whose socket the iron of the
pinion axle revolves, rests
upon two beams, which can be raised and
lowered.
There are three mills in use in milling gold ores, especially for quartz
which is not lacking in metal. They are not all turned by water-power,
but some by the strength of men,
and two of them even by the power
of beasts of burden. The first revolving one differs from the next only
in its driving wheel,
which is closed in and turned by men treading it, or by
horses, which
are placed inside, or by asses, or even by strong goats; the
eyes of
these beasts are covered by linen bands. The second mill, both
when pushed and turned round, differs from the two
above by having an
upright axle in the place of the horizontal one;
this axle has at its lower end
a disc, which two workmen turn by
treading back its cleats with their feet,
though frequently one man
sustains all the labour; or sometimes there
projects from the axle a
pole which is turned by a horse or an ass, for which
reason it is
called an The toothed drum which is at the upper end
of the axle turns the drum
which is made of rundles, and together with it the
millstone.
The third mill is turned round and round, and not pushed by hand; but
between this and the others there is a great distinction, for the lower
millstone is so shaped at the top that it can hold within it the upper
mill
stone, which revolves around an iron axle; this axle is
fastened in the
centre of the lower stone and passes through the upper
stone. A workman,
by grasping in his hand an upright iron bar placed in the
upper millstone,
moves it round. The middle of the upper millstone is bored through, and
the ore, being
thrown into this opening, falls down upon the lower millstone
and is
there ground to powder, which gradually runs out through its opening;
it is washed by various methods before it is mixed with quicksilver,
which I will explain presently.
Some people build a machine which at one and the same time can crush,
grind, cleanse, and wash the gold ore, and mix the gold with
quicksilver. This machine has one water-wheel, which is turned by a stream striking its
buckets; the main axle on one side of the water-wheel has long cams,
which
raise the stamps that crush the dry ore. Then the crushed ore is thrown
into the hopper of the upper millstone,
and gradually falling through the
opening, is ground to powder. The lower millstone is square, but has a round
depression in which the
round, upper millstone turns, and it has an outlet
from which the
powder falls into the first tub. A vertical iron axle is dove
tailed into a cross-piece, which is in
turn fixed into the upper millstone;
the upper pinion of this axle is
held in a bearing fixed in a beam; the drum
of the vertical axle is
made of rundles, and is turned by the toothed drum
on the main axle,
and thus turns the millstone. The powder falls continually
into the first tub, together with water,
and from there runs into a second tub
which is set lower down, and out
of the second into a third, which is the
lowest; from the third, it
generally flows into a small trough hewn out of a
A—FIRST MILL. B—WHEEL TURNED BY GOATS. C—SECOND MILL.
D—DISC OF
UPRIGHT AXLE. E—ITS TOOTHED DRUM. F—THIRD
MILL. G—SHAPE OF LOWER
MILLSTONE. H—SMALL UPRIGHT AXLE OF
THE SAME. I—ITS OPENING. K—LEVER
OF THE UPPER MILLSTONE.
L—ITS OPENING.Quicksilver
plank, and through a hole in the middle
of each plank there passes a small
upright axle, which is enlarged
above the plank to prevent it from dropping
into the tub lower than it
should. At the lower end of the axle three sets
of paddles intersect, each made
from two little boards fixed to the axle
opposite each other. The upper end of this axle has a pinion held by a
bearing set in a beam,
and around each of these axles is a small drum made
of rundles, each of
which is turned by a small toothed drum on a horizontal
other end is held in a hollow covered with thick iron plates in a beam. Thus
the paddles, of which there are three sets in each tub, turn round,
and
agitating the powder, thoroughly mix it with water and separate the
minute
particles of gold from it, and these are attracted by the
quicksilver and
purified. The water carries away the waste.
The quicksilver is poured
into a bag made of leather or cloth woven from
cotton, and when this bag is
squeezed, as I have described elsewhere,
the quicksilver drips through it into
a jar placed underneath. The pure gold
Some people
substitute three broad sluices for the tubs, each of which
has an angular axle
on which are set six narrow spokes, and to them are
fixed the same number of
broad paddles; the water that is poured in
strikes these paddles and turns
them round, and they agitate the powder
which is mixed with the water and
separate the metal from it. If the powder which is being treated contains
gold particles, the first
method of washing is far superior, because the quick
silver in the
tubs immediately attracts the gold; if it is powder in which
are the
small black stones from which tin is smelted, this latter method is
not
to be despised. It is very advantageous to place interlaced fir boughs
in the sluices in
which such tin-stuff is washed, after it has run through the
launders
from the mills, because the fine tin-stone is either held back by the
twigs, or if the current carries them along they fall away from the
water
and settle down.
A—WATER-WHEEL. B—AXLE. C—STAMP. D—HOPPER IN THE UPPER
MILLSTONE.
E—OPENING PASSING THROUGH THE CENTRE. F—LOWER
MILLSTONE. G—ITS
ROUND DEPRESSION. H—ITS OUTLET.
I—IRON AXLE. K—ITS CROSSPIECE. L—BEAM.
M—DRUM
OF RUNDLES ON THE IRON AXLE. N—TOOTHED DRUM OF MAIN AXLE.
O—TUBS.
P—THE SMALL PLANKS. Q—SMALL UPRIGHT AXLES.
R—ENLARGED PART OF ONE.
Seven methods of washing are in common use for the ores of many
metals;
for they are washed either in a simple buddle, or in a divided buddle,
or in an ordinary strake, or in a large tank, or in a short strake, or
in a canvas
strake, or in a jigging sieve. Other methods of washing are either peculiar
to some particular metal,
or are combined with the method of crushing wet
ore by stamps.
A simple buddle is made in the following way.
In the first place, the head
is higher than the rest of the buddle, and
is three feet long and a foot and a half
broad; this head is made of
planks laid upon a timber and fastened, and
on both sides, side-boards
are set up so as to hold the water, which flows in
through a pipe or
trough, so that it shall fall straight down. The middle of
the head is somewhat depressed in order that the broken
rock and the larger
metallic particles may settle into it. The buddle is sunk into the earth to a
depth of three-quarters of a foot
below the head, and is twelve feet long and
a foot and a half wide and
deep; the bottom and each side are lined with
planks to prevent the
earth, when it is softened by the water, from falling
in or from
absorbing the metallic particles. The lower end of the buddle is
obstructed by a board, which is not as
high as the sides. To this straight
buddle there is joined a second transverse buddle, six
feet long and a foot
and a half wide and deep, similarly lined with
planks; at the lower
that the water can flow
away: this water falls into a launder and is carried
outside the
building. In this simple buddle is washed the metallic material
which has passed
on to the floor of the works through the five large sieves. When this has been gathered into a heap, the washer throws it into the head
of the buddle, and water is poured upon it through the pipe or small
trough,
and the portion which sinks and settles in the middle of the
head compart
ment he stirs with a wooden scrubber,—this is
what we will henceforth call
the implement made of a stick to which is
fixed a piece of wood a foot long
and a palm broad. The water is made turbid by this stirring, and carries
the mud and sand
and small particles of metal into the buddle below. Together with the broken rock, the larger metallic particles remain in the
head compartment, and when these have been removed, boys throw them
upon
the platform of a washing tank or the short strake, and separate
them from
the broken rock. When the buddle is full of mud and sand, the washer closes
the pipe
through which the water flows into the head; very soon the
water which
remains in the buddle flows away, and when this has taken
A—HEAD OF BUDDLE. B—PIPE. C—BUDDLE. D—BOARD.
E—TRANSVERSE BUDDLE.
F—SHOVEL. G—SCRUBBER.
minute particles of metal, and washes them on a canvas
strake. Sometimes
before the buddles have been filled full, the boys throw the
material into a
bowl and carry it to the strakes and wash it.
Pulverized ore is washed in the head of this kind of a buddle; but usually
when tin-stone is washed in it, interlacing fir boughs are put into the
buddle, in
the same manner as in the sluice when wet ore is crushed
with stamps. The
larger tin-stone particles, which sink in the upper part of the
buddle,
are washed separately in a strake; those particles which are of
medium
size, and settle in the middle part, are washed separately in
the same way;
and the mud mixed with minute particles of tin-stone,
which has settled in
the lowest part of the buddle below the fir
boughs, is washed separately on
the canvas strakes.
The divided buddle differs from the last one by having several
cross
boards, which, being placed inside it, divide it off like
steps; if the buddle
is twelve feet long, four of them are placed
within; if nine feet long, three. The nearer each one is to the head, the greater is its height; the further
from
the head, the lower it is; and so when the highest is a foot and a
palm high,
A—PIPE. B—CROSS LAUNDER. C—SMALL TROUGHS. D—HEAD OF
THE BUDDLE.
E—WOODEN SCRUBBER. F—DIVIDING BOARDS.
G—SHORT STRAKE.
digits, and the lowest a
foot and one digit. In this buddle is generally washed
that metalliferous material which has
been sifted through the large sieve
into the tub containing water. This material is continuously thrown with
an iron shovel into the head
of the buddle, and the water which has been
let in is stirred up by a
wooden scrubber, until the buddle is full, then the
cross-boards are
taken out by the washer, and the water is drained off; next
the
metalliferous material which has settled in the compartments is again
washed, either on a short strake or on the canvas strakes or in the
jigging
sieves. Since a short strake is often united with the upper part of this buddle,
a pipe in the first place carries the water into a cross launder, from
which it
flows down through one little launder into the buddle, and
through another
into the short strake.
An ordinary strake, so far as the planks are concerned, is not unlike the
last two. The head of this, as of the others, is first made of earth stamped
down,
then covered with planks; and where it is necessary, earth is
thrown in
and beaten down a second time, so that no crevice may remain
through
which water carrying the particles of metal can escape. The water
ought to fall straight down into the strake, which has a
length of eight feet
A—HEAD B—STRAKE. C—TROWEL. D—SCRUBBER. E—CANVAS
F—ROD BY
WHICH THE CANVAS IS MADE SMOOTH.
which then extends to a settling pit outside the building. A boy with
a shovel or a ladle takes the impure concentrates or impure
tin-stone from a
heap, and throws them into the head of the strake or
spreads them over it. A washer with a wooden scrubber then agitates them in the strake, whereby
the mud mixed with water flows away into the transverse launder, and
the
concentrates or the tin-stone settle on the strake. Since sometimes the
concentrates or fine tin-stone flow down together
with the mud into the
transverse launder, a second washer closes it,
after a distance of about six feet,
with a cross-board and frequently
stirs the mud with a shovel, in order that
when mixed with water it may
flow out into the settling-pit; and there
remains in the launder only
the concentrates or tin-stone. The tin-stuff
of Schlackenwald and Erbisdroff is washed in this kind of
a strake once
or twice; those of Altenberg three or four times; those
of Geyer often
seven times; for in the ore at Schlackenwald and
Erbisdorff the tin-stone
particles are of a fair size, and are crushed
with stamps; at Altenberg they
are of much smaller size, and in the
broken ore at Geyer only a few particles
of tin-stone can be seen
occasionally.
This method of washing was first devised by the miners who treated
tin
ore, whence it passed on from the works of the tin workers to those of the
silver workers and others; this system is even more reliable than
washing in jigging-sieves. Near this ordinary strake there is generally a
canvas strake.
In modern times two ordinary strakes, similarly made, are generally
joined together; the head of one is three feet distant from that of the
other,
while the bodies are four feet distant from each other, and
there is only one
cross launder under the two strakes. One boy shovels, from the heap into the
head of each, the concentrates
or tin-stone mixed with mud. There are
two washers, one of whom sits at the right side of one strake,
and the
other at the left of the other strake, and each pursues his
task, using the
following sort of implement. Under each strake is a sill, from a socket in
which a round pole rises,
and is held by half an iron ring in a beam of the
building, so that it
may revolve; this pole is nine feet long and a palm
thick. Penetrating the pole is a small round piece of wood, three palms
long
and as many digits thick, to which is affixed a small board two feet
long and five digits wide, in an opening of which one end of a small
axle
revolves, and to this axle is fixed the handle of a little
scrubber. The other
end of this axle turns in an opening of a second board, which
is likewise fixed
to a small round piece of wood; this round piece,
like the first one, is three
palms long and as many digits thick, and
is used by the washer as a handle. The little scrubber is made of a stick three feet long, to the end of which
is
fixed a small tablet of wood a foot long, six digits broad, and a
digit and a
half thick. The washer constantly moves the handle of this implement
with one hand;
in this way the little scrubber stirs the concentrates or
the fine
tin-stone mixed with mud in the head of the strake, and the mud, on
being stirred, flows on to the strake. In the other hand he holds a second
A—UPPER CROSS LAUNDER. B—SMALL LAUNDERS. C—HEADS OF
STRAKES.
D—STRAKES. E—LOWER TRANSVERSE LAUNDER.
F—SETTLING PIT. G—SOCKET
IN THE SILL. H—HALVED IRON
RINGS FIXED TO BEAM. I—POLE. K—ITS LITTLE
SCRUBRER.
L—SECOND SMALL SCRUBBER.
lessly stirs
the concentrates or tin-stone which have settled in the upper
part of
the strake; in this way the mud and water flow down into the
transverse
launder, and from it into the settling-pit which is outside the
building.
Before the short strake and the jigging-sieve had been invented,
metallifer
ous ores, especially tin, were crushed dry with stamps
and washed in a large
trough hollowed out of one or two tree trunks;
and at the head of this trough
was a platform, on which the ore was
thrown after being completely crushed. The washer pulled it down into the trough with a wooden scrubber which
had a long handle, and when the water had been let into the trough, he
stirred
the ore with the same scrubber.
A—TROUGH. B—PLATFORM. C—WOODEN SCRUBBER.
The short strake is narrow in the upper part where the water flows down
into it through the little launder; in fact it is only two feet wide;
at the lower
end it is wider, being three feet and as many palms. At the sides, which are
six feet long, are fixed boards two palms high. In other respects the head
resembles the head of the simple buddle,
except that it is not depressed in the
middle. Beneath is a cross launder closed by a low board.
In this short
strake not only is ore agitated and washed with a wooden
scrubber, but boys
in tubs. The short strake is now rarely employed by miners, owing to the
carelessness of the boys, which has been frequently detected; for this
reason, the jigging-sieve has taken its place. The mud which settles in the
launder, if the ore is rich, is taken up
and washed in a jigging-sieve or on a
canvas strake.
A—SHORT STRAKE. B—SMALL LAUNDER. C—TRANSVERSE LAUNDER.
D—WOODEN
SCRUBBER.
A canvas strake is made in the following way.
Two beams, eighteen feet
long and half a foot broad and three palms
thick, are placed on a slope; one
half of each of these beams is
partially cut away lengthwise, to allow the ends
of planks to be
fastened in them, for the bottom is covered by planks three
feet long,
set crosswise and laid close together. One half of each supporting
beam is left intact and rises a palm above
the planks, in order that the water
that is running down may not escape
at the sides, but shall flow straight
down. The head of the strake is higher than the rest of the body, and slopes
so as to enable the water to flow away. The whole strake is covered by six
stretched pieces of canvas, smoothed
with a stick. The first of them occupies
the lowest division, and the second is so
laid as to slightly overlap it; on
A—BEAMS. B—CANVAS. C—HEAD OF STRAKE. D—SMALL LAUNDER.
E—SETTLING
PIT OR TANK. F—WOODEN SCRUBBER.
G—TUBS.
the second division, the third is similarly laid, and so
on, one on the other. If they are laid in the opposite way, the water flowing down carries the
concentrates or particles of tin-stone under the canvas, and a useless
task
is attempted. Boys or men throw the concentrates or tin-stuff mixed with
mud into the
head of the strake, after the canvas has been thus stretched,
and
having opened the small launder they let the water flow in; then
they
stir the concentrates or tin-stone with a wooden scrubber till the water
carries them all on to the canvas; next they gently sweep the linen
with
the wooden scrubber until the mud flows into the settling-pit or
into the
transverse launder. As soon as there is little or no mud on the canvas, but
only
concentrates or tin-stone, they carry the canvas away and wash it in a
tub placed close by. The tin-stone settles in the tub, and the men return
immediately to the
same task. Finally, they pour the water out of the tub,
and collect the
concentrates or tin-stone. However, if either concentrates
or tin-stone have washed down from the
canvas and settled in the settling
pit or in the transverse
launder, they wash the mud again.
Some neither remove the canvas nor wash it in the tubs, but place over
with nails. They agitate the metalliferous material with wooden scrubbers
and wash
it in a similar way. As soon as little or no mud remains on the
canvas, but only concentrates
or fine tin-stone, they lift one beam so that
the whole strake rests on
the other, and dash it with water, which has been
drawn with buckets
out of the small tank, and in this way all the sediment
which clings to
the canvas falls into the trough placed underneath. This
trough is hewn out of a tree and placed in a ditch dug in the
ground; the
interior of the trough is a foot wide at the top, but
narrower in the bottom,
because it is rounded out. In the middle of this trough they put a cross
board, in order that
the fairly large particles of concentrates or fairly large
sized
tin-stone may remain in the forepart into which they have fallen, and
the fine concentrates or fine tin-stone in the lower part, for the
water flows
from one into the other, and at last flows down through an
opening into the
pit. As for the fairly large-sized concentrates or tin-stone which have been
removed from the trough, they are washed again on the ordinary strake.
A—CANVAS STRAKE. B—MAN DASHING WATER ON THE CANVAS.
C—BUCKET.
D—BUCKET OF ANOTHER KIND. E—MAN REMOVING
CONCENTRATES OR TIN-STONE
FROM THE TROUGH.
strake. By this method, the canvas lasts longer because it remains fixed,
and
nearly double the work is done by one washer as quickly as can be done
by two washers by the other method.
The jigging sieve has recently come into use by miners.
The
metalliferous material is thrown into it and sifted in a tub nearly
full of water. The sieve is shaken up and down, and by this movement all the material
below the size of a pea passes through into the tub, and the rest
remains on the
bottom of the sieve. This residue is of two kinds, the metallic particles,
which occupy the
lower place, and the particles of rock and earth, which
take the higher
place, because the heavy substance always settles, and the
light is
borne upward by the force of the water. This light material is taken
away with a limp, which is a thin tablet of
wood almost semicircular in
shape, three-quarters of a foot long, and
half a foot wide. Before the
lighter portion is taken away the contents of the sieve are
generally divided
crosswise with a limp, to enable the water to
penetrate into it more quickly. Afterward fresh material is again thrown into the sieve and shaken up and
down, and when a great quantity of metallic particles have settled in
the sieve,
they are taken out and put into a tray close by. But since there fall into
the tub with the mud, not only particles of
gold or silver, but also of sand,
pyrites,
water cannot separate these from the metallic
particles because they are all
heavy, this muddy mixture is washed a
second time, and the part which is
useless is thrown away. To prevent the sieve passing this sand again too
quickly, the washer
lays small stones or gravel in the bottom of the sieve. However, if the sieve is not shaken straight up and down, but is tilted to
one
side, the small stones or broken ore move from one part to another,
and the
metallic material again falls into the tub, and the operation
is frustrated. The miners of our country have made an even finer sieve, which does not
fail even with unskilled washers; in washing with this sieve they have
no
need for the bottom to be strewn with small stones. By this method the mud
settles in the tub with the very fine metallic
particles, and the larger sizes of
metal remain in the sieve and are
covered with the valueless sand, and this
is taken away with a limp. The concentrates which have been collected
are smelted together with
other things. The mud mixed with the very fine
metallic particles is washed for a
third time and in the finest sieve, whose
bottom is woven of hair. If the ore is rich in metal, all the material which
has been removed by
the limp is washed on the canvas strakes, or if the ore
is poor it is
thrown away.
I have explained the methods of washing which are used in common for
the
ores of many metals. I now come to another method of crushing ore,
for I ought to speak of
this before describing those methods of washing which
are peculiar to
ores of particular metals.
In the year 1512, George, the illustrious Duke of Saxony
A—FINE SIEVES. B—LIMP. C—FINER SIEVE. D—FINEST
SIEVE
and wise Sigismund Maltitz, father of John,
Bishop of Meissen. Reject
ing the dry stamps, the large sieve, and the stone mills of
Dippolds
walde and Altenberg, in which places are dug the small
black stones
from which tin is smelted, he invented a machine which
could crush the ore
wet under iron-shod stamps. That is called “wet ore” which is softened by
water which
flows into the mortar box, and they are sometimes called “wet
stamps” because they are drenched by the same water; and on the
other hand, the
other kinds are called “dry stamps” or
“dry ore,” because no water is used
to soften the ore when
the stamps are crushing. But to return to our subject.
This machine is not dissimilar to the one which crushes the ore with dry
iron-shod stamps, but the heads of the wet stamps are larger by half
than the
heads of the others. The mortar-box, which is made of oak or beech timber, is
set up in the
space between the upright posts; it does not open in front, but
at one
end, and it is three feet long, three-quarters of a foot wide, and one foot
and six digits deep. If it has no bottom, it is set up in the same way over a
slab of hard,
smooth rock placed in the ground, which has been dug down a
little. The joints are stopped up all round with moss or cloth rags.
If
the mortar has a bottom, then an iron sole-plate, three feet long,
three
quarters of a foot wide, and a palm thick, is placed in it. In the opening
in the end of the mortar there is fixed an iron plate
full of holes, in such a
way that there is a space of two digits
between it and the shoe of the nearest
stamp, and the same distance
between this screen and the upright post, in
an opening through which
runs a small but fairly long launder. The crushed
particles of silver ore flow through this launder with the
water into a settling
pit, while the material which settles in the
launder is removed with an iron
shovel to the nearest planked floor;
that material which has settled in the
pit is removed with an iron
shovel on to another floor. Most people make
two launders, in order that while the workman empties
one of them of the
accumulation which has settled in it, a fresh
deposit may be settling in the
other. The water flows in through a small launder at the other end of the
mortar that is near the water-wheel which turns the machine. The workman
throws the ore to be crushed into the mortar in such a way
that the pieces,
when they are thrown in among the stamps, do not
impede the work. By
this method a silver or gold ore is crushed very fine by the
stamps.
When tin ore is crushed by this kind of iron-shod stamps, as soon as
crushing begins, the launder which extends from the screen discharges
the
water carrying the fine tin-stone and fine sand into a transverse
trough,
from which the water flows down through the spouts, which
pierce the side of
the trough, into the one or other of the large
buddles set underneath. The
reason why there are two is that, while the washer empties the one
which is
filled with fine tin-stone and sand, the material may flow
into the other. Each buddle is twelve feet long, one cubit deep, and a foot and a half broad.
The tin-stone which settles in the upper part of the buddles is called the
large size; these are frequently stirred with a shovel, in order that
the
medium sized particles of tin-stone, and the mud mixed with the
very fine
A—MORTAR. B—OPEN END OF MORTAR. C—SLAB OF ROCK.
D—IRON SOLE PLATES.
E—SCREEN. F—LAUNDER.
G—WOODEN SHOVEL. H—SETTLING PIT. I—IRON
SHOVEL.
K—HEAP OF MATERIAL WHICH HAS SETTLED. L—ORE WHICH REQUIRES
CRUSHING. M—SMALL LAUNDER.The particles of medium size generally
settle in the middle part of the
buddle, where they are arrested by interwoven
fir twigs. The mud which flows down with the water settles between the
twigs and
the board which closes the lower end of the buddle. The tin-stone
of large size is removed separately from the buddle with a
shovel; those
of medium size are also removed separately, and likewise
the mud is removed
separately, for they are separately washed on the
canvas strakes and on
the ordinary strake, and separately roasted and
smelted. The tin-stone
which has settled in the middle part of the buddle, is
also always washed
separately on the canvas strakes; but if the
particles are nearly equal in size
to those which have settled in the
upper part of the buddle, they are washed
with them in the ordinary
strake and are roasted and smelted with them. However, the mud is never washed with the others, either on the canvas
strakes or on the ordinary strake, but separately, and the fine
tin-stone which
is obtained from it is roasted and smelted separately. The two large buddles
discharge into a cross trough, and it again
empties through a launder into
a settling-pit which is outside the
building.
A—LAUNDER REACHING TO THE SCREEN. B—TRANSVERSE TROUGH.
C—SPOUTS.
D—LARGE BUDDLES. E—SHOVEL.
F—INTERWOVEN TWIGS. G—BOARDS CLOSING
THE BUDDLES.
H—CROSS TROUGH.
This method of washing has lately undergone a considerable change; for
the launder which carries the water, mixed with the crushed tin-stone
and
fine sand which flow from the openings of the screen, does not
reach to a
transverse trough which is inside the same room, but runs
straight through
a partition into a small settling-pit. A boy draws a three-toothed rake
through the material which has settled
in the portion of the launder outside
the room, by which means the
larger sized particles of tin-stone settle at the
bottom, and these the
washer takes out with the wooden shovel and carries
into the room; this
material is thrown into an ordinary strake and swept
with a wooden
scrubber and washed. As for those tin-stone particles which
the water carries off from the
strake, after they have been brought back on to
the strake, he washes
them again until they are clean.
The remaining tin-stone, mixed with sand, flows into the small settling-pit
which is within the building, and this discharges into two large
buddles. The
tin-stone of moderate size, mixed with those of fairly large size,
settle in the
upper part, and the small size in the lower part; but
both are impure, and
for this reason they are taken out separately and
the former is washed twice,
A—FIRST LAUNDER. B—THREE-TOOTHED RAKE. C—SMALL SETTLING
PIT. D—LARGE
BUDDLE. E—BUDDLE RESEMBLING THE SIMPLE BUDDLE.
F—SMALL ROLLER. G—
BOARDS. H—THEIR HOLES. I—SHOVEL. K—BUILDING.
L—STOVE. (THIS PICTURE
DOES NOT ENTIRELY AGREE WITH THE TEXT).
strake. Likewise the latter is washed twice, first on a canvas strake and
afterward on an ordinary strake. This buddle, which is like the simple
buddle, differs from it in the
head, the whole of which in this case is sloping,
while in the case of
the other it is depressed in the centre. In order that the
boy may be able to rest the shovel with which he
cleanses the tin-stone,
this sluice has a small wooden roller which
turns in holes in two thick
boards fixed to the sides of the buddle; if
he did not do this, he would become
over-exhausted by his task, for he
spends whole days standing over these
labours. The large buddle, the one like the simple buddle, the ordinary
strake,
and the canvas strakes, are erected within a special building. In
this building there is a stove that gives out heat through the
earthen tiles
or iron plates of which it is composed, in order that the
washers can pursue
their labours even in winter, if the rivers are not
completely frozen over.
On the canvas strakes are washed the very fine tin-stone mixed with
mud
which has settled in the lower end of the large buddle, as well as
in
the lower end of the simple buddle and of the ordinary strake. The canvas
is cleaned in a trough hewn out of one tree trunk and
partitioned off with
two boards, so that three compartments are made. The first and second pieces
of canvas are washed in the first
compartment, the third and fourth in the
second compartment, the fifth
and sixth in the third compartment. Since
among the very fine tin-stone there are usually some grains of
stone, rock,
or marble, the master cleanses them on the ordinary
strake, lightly brushing
the top of the material with a broom, the
twigs of which do not all run the
same way, but some straight and some
crosswise. In this way the water
carries off these impurities from the strake into
the settling-pit because they
are lighter, and leaves the tin-stone on
the table because it is heavier.
Below all buddles or strakes, both inside and outside the building, there
are placed either settling-pits or cross-troughs into which they
discharge,
in order that the water may carry on down into the stream
but very few
of the most minute particles of tin-stone. The large settling-pit which is
outside the building is generally made
of joined flooring, and is eight feet in
length, breadth and depth. When a large quantity of mud, mixed with
very fine tin-stone, has
settled in it, first of all the water is let out by with
drawing a
plug, then the mud which is taken out is washed outside the house
on
the canvas strakes, and afterward the concentrates are washed on the
strake which is inside the building. By these methods the very finest tin
stone is made clean.
The mud mixed with the very fine tin-stone, which has neither settled
in
the large settling-pit nor in the transverse launder which is outside the
room and below the canvas strakes, flows away and settles in the bed of
the
stream or river. In order to recover even a portion of the fine tin-stone,
many miners
erect weirs in the bed of the stream or river, very much like
those
that are made above the mills, to deflect the current into the races
through which it flows to the water-wheels. At one side of each weir there
is an area dug out to a depth of five or
six or seven feet, and if the nature of
A—LAUNDER FROM THE SCREEN OF THE MORTAR-BOX. B—THREE-TOOTHED
RAKE.
C—SMALI. SETTLING-PIT. D—CANVAS. E—STRAKES.
F—BROOMS.Thus, when the water of the river or stream in autumn and winter inundates
the land, the gates of the weir are closed, by which means the current
carries
the mud mixed with fine tin-stone into the area. In spring and summer
this mud is washed on the canvas strakes or on the
ordinary strake, and
even the finest black-tin is collected. Within a distance of four thousand
fathoms along the bed of the stream
or river below the buildings in which
the tin-stuff is washed, the
miners do not make such weirs, but put inclined
fences in the meadows,
and in front of each fence they dig a ditch of the
same length, so that
the mud mixed with the fine tin-stone, carried along by the
stream or
river when in flood, may settle in the ditch and cling to the fence.
When this mud is collected, it is likewise washed on canvas strakes and on
the ordinary strake, in order that the fine tin-stone may be separated
from
it. Indeed we may see many such areas and fences collecting mud of this
kind
in Meissen below Altenberg in the river Moglitz,—which is always of a
reddish colour when the rock containing the black tin is being crushed
under
the stamps.
A—RIVER. B—WEIR. C—GATE. D—AREA. E—MEADOW.
F—FENCE. G—DITCH.
But to return to the stamping machines.
Some usually set up four
machines of this kind in one place, that is to
say, two above and the same
number below. By this plan it is necessary that the current which has been
diverted
should fall down from a greater height upon the upper water
wheels,
because these turn axles whose cams raise heavier stamps. The
stamp-stems of the upper machines should be nearly twice as long as
the stems
of the lower ones, because all the mortar-boxes are placed on
the same level. These stamps have their tappets near their upper ends, not as in the case of
the lower stamps, which are placed just above the bottom. The water flowing
down from the two upper water-wheels is caught in two
broad races, from
which it falls on to the two lower water-wheels. Since all these machines
have the stamps very close together, the stems
should be somewhat cut away,
to prevent the iron shoes from rubbing
each other at the point where they are
set into the stems. Where so many machines cannot be constructed, by
reason of the
narrowness of the valley, the mountain is excavated and
levelled in two
places, one of which is higher than the other, and in this case
two
machines are constructed and generally placed in one building. A
broad race receives in the same way the water which flows down from
the
upper water-wheel, and similarly lets it fall on the lower
water-wheel. The
mortar-boxes are not then placed on one level, but each on the level
which
is appropriate to its own machine, and for this reason, two
workmen are then
required to throw ore into the mortar-boxes. When no stream can be
diverted which will fall from a higher place upon
the top of the water-wheel,
one is diverted which will turn the foot of
the wheel; a great quantity of
water from the stream is collected in
one pool capable of holding it, and
from this place, when the gates are
raised, the water is discharged against
the wheel which turns in the
race. The buckets of a water-wheel of this
kind are deeper and bent back,
projecting upward; those of the former
are shallower and bent forward,
inclining downward.
Further, in the Julian and Rhaetian Alps
Mountains, gold or even silver
ore is now put under stamps, which are
sometimes placed more than
twenty in a row, and crushed wet in a long mortar
box. The mortar has two plates full of holes through which the ore, after
being crushed, flows out with the water into the transverse launder
placed
underneath, and from there it is carried down by two spouts into
the heads of
the canvas strakes. Each head is made of a thick broad plank, which can be
raised and set
upright, and to which on each side are fixed pieces projecting
upward. In this plank there are many cup-like depressions equal in size and
similar in shape, in each of which an egg could be placed. Right down in
these depressions are small crevices which can retain the
concentrates of gold
or silver, and when the hollows are nearly filled
with these materials, the
plank is raised on one side so that the
concentrates will fall into a large bowl. The cup-like depressions are washed out by dashing them with water.
These
A—FIRST MACHINE. B—ITS STAMPS. C—ITS MORTAR-BOX.
D—SECOND MACHINE.
E—ITS STAMPS. F—ITS MORTAR-BOX.
G—THIRD MACHINE. H—ITS STAMPS. I—ITS
MORTAR-BOX.
K—FOURTH MACHINE. L—ITS STAMPS. M—ITS MORTAR-BOX.
settled on the canvas. This bowl is smooth and two digits wide and deep,
being in shape very
similar to a small boat; it is broad in the fore part,
narrow in the
back, and in the middle of it there is a cross groove, in which
the
particles of pure gold or silver settle, while the grains of sand, since
they
are lighter, flow out of it.
In some parts of Moravia, gold ore, which consists of quartz mixed with
gold, is placed under the stamps and crushed wet. When crushed fine it
flows out through a launder into a trough, is there
stirred by a wooden
scrubber, and the minute particles of gold which
settle in the upper end of
the trough are washed in a black bowl.
A—STAMPS. B—MORTAR. C—PLATES FULL OF HOLES.
D—TRANSVERSE LAUNDER.
E—PLANKS FULL OF CUP-LIKE
DEPRESSIONS. F—SPOUT. G—BOWL INTO WHICH THE
CONCENTRATES
FALL. H—CANVAS STRAKE. I—BOWLS SHAPED LIKE A SMALL BOAT.
K—SETTLING-PIT UNDER THE CANVAS STRAKE.
So far I have spoken of machines which crush wet ore with iron-shod
stamps. I will now explain the methods of washing which are in a measure
peculiar to the ore of certain metals, beginning with gold. The ore which
contains particles of this metal, and the sand of streams
and rivers which
are also washed in troughs. More than one method is employed for washing
on frames, for these frames
either pass or retain the particles or concentrates
of gold; they pass
them if they have holes, and retain them if they have
no holes. But either the frame itself has holes, or a box is substituted for
it;
if the frame itself is perforated it passes the particles or concentrates
of gold into a trough; if the box has them, it passes the gold material
into
the long sluice. I will first speak of these two methods of washing.
The
frame is made of two planks joined together, and is twelve feet long
and
three feet wide, and is full of holes large enough for a pea to
pass. To prevent
the ore or sand with which the gold is mixed from falling out
at the sides,
small projecting edge-boards are fixed to it. This frame is set upon two
stools, the first of which is higher than the
second, in order that the gravel
and small stones can roll down it. The washer throws the ore or sand into
the head of the frame, which is
higher, and opening the small launder, lets
the water into it, and then
agitates it with a wooden scrubber. In this way,
the gravel and small stones roll down the frame on to the
ground, while the
A—HEAD OF FRAME. B—FRAME. C—HOLES. D—EDGE-BOARDS.
E—STOOLS
F—SCRUBBER. G—TROUGH. H—LAUNDER.
I—BOWL.
holes into the trough which is
placed under the frame, and after being
collected are washed in the
bowl.
A box which has a bottom made of a plate full of holes, is placed over
the upper end of a sluice, which is fairly long but of moderate width. The
gold material to be washed is thrown into this box, and a great
quantity of
water is let in. The lumps, if ore is being washed, are mashed with an iron
shovel. The fine portions fall through the bottom of the box into the sluice,
but the coarse pieces remain in the box, and these are removed with a
scraper
through an opening which is nearly in the middle of one side. Since a large
amount of water is necessarily let into the box, in order
to prevent it from
sweeping away any particles of gold which have
fallen into the sluice, the
sluice is divided off by ten, or if it is
as long again, by fifteen riffles. These
riffles are placed equidistant from one another, and each is
higher than the one
next toward the lower end of the sluice. The little compartments which are
thus made are filled with the material
and the water which flows through
A—SLUICE. B—BOX. C—BOTTOM OF INVERTED BOX. D—OPEN
PART OF IT. E—IRON
HOE. F—RIFFLES. G—SMALL LAUNDER.
H—BOWL WITH WHICH SETTLINGS ARE TAKEN
AWAY. I—BLACK BOWL IN
WHICH THEY ARE WASHED.
to flow over clear, the
little launder through which this water enters into the
box is closed,
and the water is turned in another direction. Then the
lowest riffle is removed from the sluice, and the sediment
which has
accumulated flows out with the water and is caught in a bowl. The
riffles are removed one by one and the sediment from each is taken
into a
separate bowl, and each is separately washed and cleansed in a
bowl. The
larger particles of gold concentrates settle in the higher
compartments, the
smaller size, in the lower compartments. This bowl is shallow and smooth,
and smeared with oil or some other
slippery substance, so that the tiny particles
of gold may not cling to
it, and it is painted black, that the gold may be more
easily
discernible; on the exterior, on both sides and in the middle, it is
slightly hollowed out in order that it may be grasped and held firmly
in the
hands when shaken. By this method the particles or concentrates of gold
settle in the back
part of the bowl; for if the back part of the bowl is
tapped or shaken
with one hand, as is usual, the contents move toward the
fore part. In this way the Moravians, especially, wash gold ore.
The gold particles are also caught on frames which are either bare or
covered. If bare, the particles are caught in pockets; if covered, they
A—PLANK. B—SIDE-BOARDS. C—IRON WIRE. D—HANDLES.
Pockets are made in various ways, either with iron
wire or small
cross-boards fixed to the frame, or by holes which are sunk
into the
sluice itself or into its head, but which do not quite go through. These holes are round or square, or are grooves running crosswise.
The
frames are either covered with skins, pieces of cloth, or turf,
which I will
deal with one by one in turn.
In order to prevent the sand which contains the particles of gold from
spilling out, the washer fixes side-boards to the edges of a plank
which is six
feet long and one and a quarter wide. He then lays crosswise many iron
wires a digit apart, and where they
join he fixes them to the bottom plank
with iron nails. Then he makes the head of the frame higher, and into this
he throws the
sand which needs washing, and taking in his hands the handles
which are
at the head of the frame, he draws it backward and forward
several
times in the river or stream. In this way the small stones and gravel
flow down along the frame, and
the sand mixed with particles of gold remains
in the pockets between
the strips. When the contents of the pockets have
been shaken out and collected in
one place, he washes them in a bowl and
thus cleans the gold dust.
Other people, among whom are the Lusitanians
sluice, which is about six feet
long and a foot and a half broad, many cross
strips or riffles,
which project backward and are a digit apart. The washer
or his wife lets the water into the head of the sluice, where
he throws the sand
which contains the particles of gold. As it flows down he agitates it with a
wooden scrubber, which he moves
transversely to the riffles. He constantly
removes with a pointed wooden stick the sediment which
settles in the pockets
between the riffles, and in this way the
particles of gold settle in them,
while the sand and other valueless
materials are carried by the water into a
tub placed below the sluice. He removes the particles of metal with a small
wooden shovel into a
wooden bowl. This bowl does not exceed a foot and a
quarter in breadth, and by moving
it up and down in the stream he cleanses
the gold dust, for the
remaining sand flows out of the dish, and the gold dust
settles in the
middle of it, where there is a cup-like depression. Some make
use of a bowl which is grooved inside like a shell, but with a
smooth lip where
the water flows out. This smooth place, however, is narrower where the
grooves run into it,
and broader where the water flows out.
A—HEAD OF THE SLUICE. B—RIFFLES. C—WOODEN SCRUBBER.
D—POINTED STICK.
E—DISH. F—ITS CUP-LIKE DEPRESSION.
G—GROOVED DISH.
The cup-like pockets and grooves are cut or burned at the same time into
the bottom of the sluice; the bottom is composed of three planks ten
feet
long, and is about four feet wide; but the lower end, through
which the water
is discharged, is narrower. This sluice, which likewise has side-boards fixed
to its edges, is full
of rounded pockets and of grooves which lead to them,
there being two
grooves to one pocket, in order that the water mixed with
sand may flow
into each pocket through the upper groove, and that after the
sand has
partly settled, the water may again flow out through the lower
groove. The sluice is set in the river or stream or on the bank, and placed
on
two stools, of which the first is higher than the second in order that the
gravel and small stones may roll down the sluice. The washer throws sand
into the head with a shovel, and opening the
launder, lets in the water, which
carries the particles of metal with a
little sand down into the pockets, while
the gravel and small stones
with the rest of the sand falls into a tub placed
below the sluice. As soon as the pockets are filled, he brushes out the
concentrates and
washes them in a bowl. He washes again and again
through this sluice.
A—HEAD OF THE SLUICE. B—SIDE-BOARDS. C—LOWER END OF THE
SLUICE.
D—POCKETS. E—GROOVES. F—STOOLS.
G—SHOVEL. H—TUB SET BELOW.
I—LAUNDER.
Some people cut a number of cross-grooves, one palm distant from each
other, in a sluice similarly composed of three planks eight feet long. The
upper edge of these grooves is sloping, that the particles of gold
may slip into
them when the washer stirs the sand with a wooden shovel;
but their lower
edge is vertical so that the gold particles may thus be
unable to slide
out of them. As soon as these grooves are full of gold particles mixed
with fine
sand, the sluice is removed from the stools and raised up on its
head. The head in this case is nothing but the upper end of the planks
of
which the sluice is composed. In this way the metallic particles, being
turned over backward, fall
into another tub, for the small stones and gravel
have rolled down the
sluice. Some people place large bowls under the
sluice instead of tubs, and as
in the other cases, the unclean concentrates are
washed in the small
bowl.
The Thuringians cut rounded pockets, a digit in diameter and depth, in
the head of the sluice, and at the same time they cut grooves reaching
from
one to another. The sluice itself they cover with canvas.
The sand which
A—CROSS GROOVES. B—TUB SET UNDER THE SLUICE. C—ANOTHER
TUB.
is to be washed, is thrown into the head and stirred with a wooden
scrubber;
in this way the water carries the light particles of gold on
to the canvas,
and the heavy ones sink in the pockets, and when these
hollows are full, the
head is removed and turned over a tub, and the
concentrates are collected
and washed in a bowl. Some people make use of a sluice which has square
pockets with short
vertical recesses which hold the particles of gold. Other
workers use a sluice made of planks, which are rough by reason of
the very
small shavings which still cling to them; these sluices are
used instead of
those with coverings, of which this sluice is bare, and
when the sand is washed,
the particles of gold cling no less to these
shavings than to canvas, or skins, or
cloths, or turf. The washer sweeps the sluice upward with a broom, and
when he has washed
as much of the sand as he wishes, he lets a more abundant
supply of
water into the sluice again to wash out the concentrates, which he
collects in a tub set below the sluice, and then washes again in a
bowl. Just
as Thuringians cover the sluice with canvas, so some people cover
it with
the skins of oxen or horses. They push the auriferous sand upward with a
wooden scrubber, and by this
system the light material flows away with the
water, while the
particles of gold settle among the hairs; the skins are
afterward
washed in a tub; and the concentrates are colleced in a bowl.
A—SLUICE COVERED WITH CANVAS. B—ITS HEAD FULL OF POCKETS AND
GROOVES.
C—HEAD REMOVED AND WASHED IN A TUB. D—SLUICE WHICH
HAS SQUARE POCKETS.
E—SLUICE TO WHOSE PLANKS SMALL SHAVINGS
CLING. F—BROOM. G—SKINS OF OXEN.
H—WOODEN
SCRUBBER.
The Colchians
since many particles of gold had
clung to them when they were removed,
A—SPRING. B—SKIN. C—ARGONAUTS.
the poets invented the
“golden fleece” of the Colchians. In like manner,
it can be contrived by the methods of miners that skins
should take up, not
only particles of gold, but also of silver and
gems.
Many people cover the frame with a green cloth as long and wide as the
frame itself, and fasten it with iron nails in such a way that they can
easily
A—HEAD OF FRAME. B—FRAME. C—CLOTH. D—SMALL LAUNDER.
E—TUB SET
BELOW THE FRAME. F—TUB IN WHICH CLOTH IS
WASHED.
draw them out and remove the cloth. When the cloth appears to be golden
because of the particles which
adhere to it, it is washed in a special tub and
the particles are
collected in a bowl. The remainder which has run down into
the tub is again washed on the
frame.
Some people, in place of a green cloth, use a cloth of tightly woven
horsehair, which has a rough knotty surface. Since these knots stand out
A—CLOTH FULL OF SMALL KNOTS, SPREAD OUT. B—SMALL KNOTS MORE
CONSPICUOUSLY
SHOWN. C—TUB IN WHICH CLOTH IS WASHED.
and the
cloth is rough, even the very small particles of gold adhere to it;
these cloths are likewise washed in a tub with water.
Some people construct a frame not unlike the one covered with canvas,
but shorter. In place of the canvas they set pieces of turf in rows.
They
A—HEAD OF FRAME. B—SMALL LAUNDER THROUGH WHICH WATER FLOWS INTO
HEAD OF
FRAME. C—PIECES OF TURF. D—TROUGH PLACED UNDER
FRAME. E—TUB IN WHICH
PIECES OF TURF ARE WASHED.
wash the
sand, which has been thrown into the head of the frame, by letting
in
water. In this way the particles of gold settle in the turf, the mud and
sand,
together with the water, are carried down into the settling-pit or trough
below, which is opened when the work is finished. After all the water has
passed out of the settling-pit, the sand and mud
are carried away and washed
over again in the same manner. The particles which have clung to the turf
are afterward washed down
into the settling-pit or trough by a stronger
current of the water,
which is let into the frame through a small launder. The concentrates are finally collected and washed in a bowl.
Pliny was not
ignorant of this method of washing gold. “The ulex,” he says, “after being
dried, is burnt, and
its ashes are washed over a grassy turf, that the gold
may settle on
it.”
A—TRAY. B—BOWL-LIKE DEPRESSION. C—HANDLES.
Sand mixed with particles of gold is also washed in a tray, or in a trough
or bowl. The tray is open at the further end, is either hewn out of a
squared
trunk of a tree or made out of a thick plank to which side-boards
are
fixed, and is three feet long, a foot and a half wide, and three digits
deep. The bottom is hollowed out into the shape of an elongated bowl whose
narrow end is turned toward the head, and it has two long handles, by
which
it is drawn backward and forward in the river. In this way the fine sand
is washed, whether it contains particles of
gold or the little black stones from
which tin is made.
The Italians who come to the German mountains seeking gold, in order
to
wash the river sand which contains gold-dust and garnets,
long shallow trough hewn
out of a tree, rounded within and without, open
at one end and closed
at the other, which they turn in the bed of the stream
in such a way
that the water does not dash into it, but flows in gently. They stir the sand, which they throw into it, with a wooden hoe, also
rounded. To prevent the particles of gold or garnets from running out with
the
light sand, they close the end with a board similarly rounded, but lower
than the sides of the trough. The concentrates of gold or garnets which,
A—TROUGH. B—ITS OPEN END. C—END THAT MAY BE CLOSED.
D—STREAM.
E—HOE. F—END-BOARD. G—BAG.
with a
small quantity of heavy sand, have settled in the trough, they wash
in
a bowl and collect in bags and carry away with them.
Some people wash this kind of sand in a large bowl which can easily be
shaken, the bowl being suspended by two ropes from a beam in a
building. The sand is thrown into it, water is poured in, then the bowl is shaken, and
the muddy water is poured out and clear water is again poured in, this
being
done again and again. In this way, the gold particles settle in the back part
of the bowl
because they are heavy, and the sand in the front part because it
is
light; the latter is thrown away, the former kept for smelting. The one
who does the washing then returns immediately to his task. This method
of washing is rarely used by miners, but frequently by
coiners and goldsmiths
when they wash gold, silver, or copper. The bowl they employ has only
three handles, one of which they grasp in
their hands when they shake the
bowl, and in the other two is fastened
a rope by which the bowl is hung from
a beam, or from a cross-piece
which is upheld by the forks of two upright
posts fixed in the ground. Miners frequently wash ore in a small bowl to test
A—LARGE BOWL B—ROPES. C—BEAM. D—OTHER LARGE BOWL
WHICH COINERS
USE. E—SMALL BOWL.
it. This bowl, when shaken, is held in one hand and thumped with the other
hand. In other respects this method of washing does not differ from the
last.
I have spoken of the various methods of washing sand which contains
grains of gold; I will now speak of the methods of washing the material
in
which are mixed the small black stones from which tin is madeEight
such methods are in use, and of these two have been invented
lately. Such
metalliferous material is usually found torn away from veins and
stringers
and scattered far and wide by the impetus of water, although
sometimes The miners dig out the latter material
with a broad mattock, while they
dig the former with a pick. But they dig
out the little stones, which are not rare in this kind of
ore, with an instrument
like the bill of a duck. In districts which contain this material, if there is
an abundant supply
of water, and if there are valleys or gentle slopes and
hollows, so
that rivers can be diverted into them, the washers in summer
A—STREAM. B—DITCH. C—MATTOCK. D—PIECES OF TURF.
E—SEVEN-PRONGED FORK.
F—IRON SHOVEL. G—TROUGH.
H—ANOTHER TROUGH BELOW IT. I—SMALL WOODEN TROWEL.
it rapidly. Into the ditch is thrown the metallic material, together with the
surface material, which is six feet thick, more or less, and often
contains moss,
roots of plants, shrubs, trees, and earth; they are all
thrown in with a broad
mattock, and the water flows through the ditch. The sand and tin-stone, as
they are heavy, sink to the bottom of the
ditch, while the moss and roots, as
they are light, are carried away by
the water which flows through the ditch. The bottom of the ditch is obstructed with turf and stones in order to
prevent
the water from carrying away the tin-stone at the same time. The washers,
whose feet are covered with high boots made of hide, though
not of rawhide,
themselves stand in the ditch and throw out of it the
roots of the trees,
shrubs, and grass with seven-pronged wooden forks,
and push back the tin
stone toward the head of the ditch. After four weeks, in which they have
devoted much work and labour, they
raise the tin-stone in the following
way; the sand with which it is
mixed is repeatedly lifted from the ditch
A—TROUGH. B—WOODEN SHOVEL. C—TUB. D—LAUNDER.
E—WOODEN TROWEL.
F—TRANSVERSE TROUGH. G—PLUG.
H—FALLING WATER. I—DITCH. K—BARROW
CONVEYING MATERIAL
TO BE WASHED. L—PICK LIKE THE BEAK OF A DUCK WITH WHICH
THE MINER
DIGS OUT THE MATERIAL FROM WHICH THE SMALL STONES ARE OBTAINED.
sand flows away and only the tin-stone remains on
the shovel. The tin
stone is all collected together and washed again in a trough
by pushing it
up and turning it over with a wooden trowel, in order
that the remaining
sand may separate from it. Afterward they return to their task, which they
continue until the
metalliferous material is exhausted, or until the water can
no longer
be diverted into the ditches.
The trough which I mentioned is hewn out of the trunk of a tree and the
interior is five feet long, three-quarters of a foot deep, and six
digits wide. It is placed on an incline and under it is put a tub which contains
interwoven
fir twigs, or else another trough is put under it, the
interior of which is three
feet long and one foot wide and deep; the
fine tin-stone, which has run out
with the water, settles in the
bottom. Some people, in place of a trough,
put a square launder underneath, and
in like manner they wash the tin
stone in this by agitating it up
and down and turning it over with a small
wooden trowel. A transverse trough is put under the launder, which is
either open on
one end and drains off into a tub or settling-pit, or else is
closed
and perforated through the bottom; in this case, it drains into a
ditch
beneath, where the water falls when the plug has been partly removed.
The nature of this ditch I will now describe.
If the locality does not supply an abundance of water, the washers dig a
ditch thirty or thirty-six feet long, and cover the bottom, the full
length, with
logs joined together and hewn on the side which lies flat
on the ground. On
each side of the ditch, and at its head also, they place four logs,
one above
the other, all hewn smooth on the inside. But since the logs are laid
obliquely along the sides, the upper end of
the ditch is made four feet wide
and the tail end, two feet. The water has a high drop from a launder and
first of all it falls into
interlaced fir twigs, in order that it shall fall straight
down for the
most part in an unbroken stream and thus break up the lumps
by its
weight. Some do not place these twigs under the end of the launder,
but put a
plug in its mouth, which, since it does not entirely close the launder,
nor altogether prevent the discharge from it, nor yet allow the water
to
spout far afield, makes it drop straight down. The workman brings in a
wheelbarrow the material to be washed, and
throws it into the ditch. The
washer standing in the upper end of the ditch breaks the lumps with
a seven
pronged fork, and throws out the roots of trees, shrubs,
and grass with the
same instrument, and thereby the small black stones
settle down. When a
large quantity of the tin-stone has accumulated, which generally
happens
when the washer has spent a day at this work, to prevent it
from being
washed away he places it upon the bank, and other material
having been
again thrown into the upper end of the ditch, he continues
the task of washing. A boy stands at the lower end of the ditch, and with a thin pointed hoe
stirs up the sediment which has settled at the lower end, to prevent
the
washed tin-stone from being carried further, which occurs when the
sediment
has accumulated to such an extent that the fir branches at the
outlet of the
ditch are covered.
A—LAUNDER. B—INTERLACING FIR TWIGS. C—LOGS; THREE ON ONE
SIDE, FOR THE
FOURTH CANNOT BE SEEN BECAUSE THE DITCH IS SO FULL WITH
MATERIAL NOW BEING
WASHED. D—LOGS AT THE HEAD OF THE DITCH.
E—BARROW. F—SEVEN-PRONGED
FORK. G—HOE
The third method of washing materials of this kind follows.
Two
strakes are made, each of which is twelve feet long and a foot and a
half wide and deep. A tank is set at their head, into which the water flows
through a little
launder. A boy throws the ore into one strake; if it is of
poor quality he puts
in a large amount of it, if it is rich he puts in less. The
water is let in by removing the plug, the ore is stirred with a
wooden shovel,
and in this way the tin-stone, mixed with the heavier
material, settles
in the bottom of the strake, and the water carries
the light material into the
launder, through which it flows on to a
canvas strake. The very fine tin
stone, carried by the water, settles on to the
canvas and is cleansed. A low
cross-board is placed in the strake near the head, in order that
the largest
sized tin-stone may settle there. As soon as the strake is filled with the
material which has been washed,
he closes the mouth of the tank and continues
washing in the other
strake, and then the plug is withdrawn and the
water and tin-stone flow
down into a tank below. Then he pounds the sides
A—STRAKES. B—TANK. C—LAUNDER. D—PLUG. E—WOODEN
SHOVEL.
F—WOODEN MALLET. G—WOODEN SHOVEL WITH SHORT HANDLE.
H—THE PLUG
IN THE STRAKE. I—TANK PLACED UNDER THE
PLUG.
of the loaded strake with a wooden mallet, in order that the
tin-stone clinging
to the sides may fall off; all that has settled in
it, he throws out with a
wooden shovel which has a short handle. Silver slags which have been
crushed under the stamps, also fragments of
silver-lead alloy and of cakes
melted from pyrites, are washed in a
strake of this kind.
Material of this kind is also washed while wet, in a sieve whose bottom
is made of woven iron wire, and this is the fourth method of washing. The
sieve is immersed in the water which is contained in a tub, and is
violently
shaken. The bottom of this tub has an opening of such size that as much
water,
together with tailings from the sieve, can flow continuously out of it as
water flows into it. The material which settles in the strake, a boy either
digs over with a
three-toothed iron rake or sweeps with a wooden scrubber;
in this way
the water carries off a great part of both sand and mud. The
tin-stone or metalliferous concentrates settle in the strake and are
afterward
washed in another strake.
These are ancient methods of washing material which contains
tin
stone; there follow two modern methods. If the tin-stone mixed with
A—SIEVE. B—TUB. C—WATER FLOWING OUT OF THE BOTTOM OF IT.
D—STRAKE.
E—THREE-TOOTHED RAKE. F—WOODEN
SCRUBBER.
earth or sand is found on the slopes of mountains or hills, or
in the level fields
which are either devoid of streams or into which a
stream cannot be diverted,
miners have lately begun to employ the
following method of washing, even
in the winter months. An open box is constructed of planks, about six
feet long, three feet
wide, and two feet and one palm deep. At the upper
end on the inside, an iron plate three feet long and wide
is fixed, at a depth
of one foot and a half from the top; this plate is
very full of holes, through
which tin-stone about the size of a pea can
fall. A trough hewn from a tree
is placed under the box, and this trough is
about twenty-four feet long and
three-quarters of a foot wide and deep;
very often three cross-boards are
placed in it, dividing it off into
compartments, each one of which is lower
than the next. The turbid waters discharge into a settling-pit.
The metalliferous material is sometimes found not very deep beneath
the
surface of the earth, but sometimes so deep that it is necessary to drive
tunnels and sink shafts. It is transported to the washing-box in wheel
barrows, and when the
washers are about to begin they lay a small launder,
A—BOX. B—PERFORATED PLATE. C—TROUGH. D—CROSS-BOARDS.
E—POOL.
F—LAUNDER. G—SHOVEL. H—RAKE.
for this washing. Next, a boy throws the metalliferous material on to the
iron plate with
an iron shovel and breaks the small lumps, stirring them this
way and
that with the same implement. Then the water and sand penetra
ting the holes of the plate, fall
into the box, while all the coarse gravel remains
on the plate, and
this he throws into a wheelbarrow with the same shovel. Meantime, a younger boy continually stirs the sand under the plate with a
wooden scrubber nearly as wide as the box, and drives it to the upper
end of
the box; the lighter material, as well as a small amount of
tin-stone, is
carried by the water down into the underlying trough. The boys carry on
this labour without intermission until they have
filled four wheelbarrows
with the coarse and worthless residues, which
they carry off and throw away, or
three wheelbarrows if the material is
rich in black tin. Then the foreman
has the plank removed which was in front of the iron
plate, and on which the
boy stood. The sand, mixed with the tin-stone, is frequently pushed backward
and
forward with a scrubber, and the same sand, because it is lighter, takes
the upper place, and is removed as soon as it appears; that which takes
the
lower place is turned over with a spade, in order that any that is
light
can flow away; when all the tin-stone is heaped together, he
shovels it out
of the box and carries it away. While the foreman does this, one boy with
an iron hoe stirs the sand
mixed with fine tin-stone, which has run out of the
box and has settled
in the trough and pushes it back to the uppermost part
of the trough,
and this material, since it contains a very great amount of
tin
stone, is thrown on to the plate and washed again. The material which has
settled in the lowest part of the trough is taken
out separately and piled in a
heap, and is washed on the ordinary
strake; that which has settled in the
pool is washed on the canvas
strake. In the summer-time this fruitful
labour is repeated more often, in fact
ten or eleven times. The tin-stone
which the foreman removes from the box, is afterward
washed in a jigging
sieve, and lastly in a tub, where at length all the
sand is separated out. Finally, any material in which are mixed particles of other metals, can be
washed by all these methods, whether it has been disintegrated from
veins or
stringers, or whether it originated from
rivers.
The sixth method of washing material of this kind is even more modern
and more useful than the last. Two boxes are constructed, into each of
which water flows through spouts
from a cross trough into which it has been
discharged through a pipe or
launder. When the material has been agitated
and broken up with iron shovels by
two boys, part of it runs down and falls
through the iron plates full
of holes, or through the iron grating, and flows
out of the box over a
sloping surface into another cross trough, and from
this into a strake
seven feet long and two and a half feet wide. Then
the foreman again stirs it with a wooden scrubber that it may
become
clean. As for the material which has flowed down with the water and settled
in
the third cross trough, or in the launder which leads from it, a third boy
rakes it with a two-toothed rake; in this way the fine tin-stone
settles down
A—LAUNDER. B—CROSS TROUGH. C—TWO SPOUTS. D—BOXES.
E—PLATE.
F—
GRATING. G—SHOVELS. H—SECOND CROSS TROUGH.
I—STRAKE. K—WOODEN
SCRUBBER. L—THIRD CROSS TROUGH.
M—LAUNDER. N—THREE-TOOTHED RAKE.
and the water carries off
the valueless sand into the creek. This method
of washing is most advantageous, for four men can do the
work of washing
in two boxes, while the last method, if doubled,
requires six men, for it requires
two boys to throw the material to be
washed on to the plate and to stir it
with iron shovels; two more are
required with wooden scrubbers to keep
stirring the sand, mixed with
the tin-stone, under the plate, and to push it
toward the upper end of
the box; further, two foremen are required
to clean the tin-stone in
the way I have described. In the place of a plate
full of holes, they now fix in the boxes a
grating made of iron wire as
thick as the stalks of rye; that these may
not be depressed by the weight
and become bent, three iron bars support
them, being laid crosswise under
neath. To prevent the grating from being broken by the iron shovels with
which
the material is stirred in washing, five or six iron rods are placed on
top in cross lines, and are fixed to the box so that the shovels may
rub them
instead of the grating; for this reason the grating lasts
longer than the
easily be replaced by others.
Miners use the seventh method of washing when there is no stream of
water in the part of the mountain which contains the black tin, or
particles of
gold, or of other metals. In this case they frequently dig more than fifty
ditches on the slope
below, or make the same number of pits, six feet long,
three feet wide,
and three-quarters of a foot deep, not any great distance
from each
other. At the season when a torrent rises from storms of
great violence or long
duration, and rushes down the mountain, some of
the miners dig the
metalliferous material in the woods with broad hoes and
A—PITS. B—TORRENT. C—SEVEN-PRONGED FORK.
D—SHOVEL.
drag it to the torrent. Other miners divert the torrent into the ditches or
pits, and others
throw the roots of trees, shrubs, and grass out of the ditches
or pits
with seven-pronged wooden forks. When the torrent has run down,
they remove with shovels the uncleansed
tin-stone or particles of metal which
have settled in the ditches or
pits, and cleanse it.
The eighth method is also employed in the regions which the Lusitanians
hold in their power and sway, and is not dissimilar to the last. They drive
the mountains. Into these ditches the water, whether flowing down from
snow melted by
the heat of the sun or from rain, collects and carries together
with
earth and sand, sometimes tin-stone, or, in the case of the Lusitanians,
the particles of gold loosened from veins and stringers. As soon as the
waters of the torrent have all run away, the miners throw
the material out
of the ditches with iron shovels, and wash it in a
common sluice box.
A—GULLY. B—DITCH. C—TORRENT. D—SLUICE BOX EMPLOYED BY
THE
LUSITANIANS.
The Poles wash the impure lead from
feet
long, three feet wide, and one and one-quarter feet deep. It is mixed
with moist earth and is covered by a wet and sandy clay, and
so
first of all the clay, and afterward the ore, is dug out. The ore is carried
to a stream or river, and thrown into a trough into
which water is admitted
by a little launder, and the washer standing at
the lower end of the trough
drags the ore out with a narrow and nearly
pointed hoe, whose wooden handle
is nearly ten feet long. It is washed over again once or twice in the same
way and thus made
pure. Afterward when it has been dried in the sun
pass
through the sieve from the larger ones. of these the former are smelted
in a faggot pile and the latter in the
furnace. Of such a number then are
the methods of washing.
A—TROUGH. B—LAUNDER. C—HOE. D—SIEVE.
One method of burning is principally employed, and two of roasting.
The black tin is burned by a hot fire in a furnace similar to an oven
is burned if it is a
dark-blue colour, or if pyrites and the stone from which
iron is made
are mixed with it, for the dark blue colour if not burnt, consumes
the
tin. If pyrites and the other stone are not volatilised into fumes in a
furnace of this kind, the tin which is made from the tin-stone is
impure. The tin-stone is thrown either into the back part of the furnace, or into one
side of it; but in the former case the wood is placed in front, in the
latter
case alongside, in such a manner, however, that neither
firebrands nor
coals may fall upon the tin-stone itself or touch it. The fuel is manipulated
by a poker made of wood. The tin-stone is now stirred with a rake with two
The very fine tin-stone requires to be burned less than that of moderate
size,
and this again less than that of the largest size. While the tin-stone is being
thus burned, it frequently happens that
some of the material runs together.
A—FURNACE. B—ITS MOUTH. C—POKER. D—RAKE WITH TWO
TEETH. E—HOE.
The burned tin-stone should then be washed again on
the strake, for in this
way the material which has been run together is
carried away by the water
into the cross-trough, where it is gathered
up and worked over, and again
washed on the strake. By this method the metal is separated from that
which is devoid of
metal.
Cakes from pyrites, or
rangular pits, of which the front and top are open, and these
pits are generally
twelve feet long, eight feet wide, and three feet
deep. The cakes of melted
pyrites are usually roasted twice over, and those of
These latter
are first rolled in mud moistened with vinegar, to prevent
the fire from con
suming too much of the copper with the bitumen,
or sulphur, or orpiment, or
realgar. The cakes of pyrites are first roasted in a slow fire and afterward in
a
fierce one, and in both cases, during the whole following night, water is
let in,
of injuring the metals, although it
rarely does injure them, the water may
remove it and make the cakes
soft. The solidified juices are nearly all
harmful to the metal, when cakes or
ore of this kind are smelted. The cakes
which are to be roasted are placed on wood piled up in the
form of a crate,
and this pile is fired
A—PITS. B—WOOD. C—CAKES. D—LAUNDER.
The cakes which are made of copper smelted from schist are first thrown
upon the ground and broken, and then placed in the furnace on bundles
of
faggots, and these are lighted. These cakes are generally roasted seven
times and occasionally nine
times. While this is being done, if they are
These furnaces have
a structure like the structure of the furnaces in
which ore is smelted, except
that they are open in front; they are six
feet high and four feet wide. As
for this kind of furnace, three of them are required for one of those
in which
the cakes are melted. First of all they are roasted in the first furnace, then
when they are
cooled, they are transferred into the second furnace and again
roasted;
later they are carried to the third, and afterward back to the first,
and this order is preserved until they have been roasted seven or nine
times.
A—CAKES. B—BUNDLES OF FAGGOTS. C—FURNACES.
END OF BOOK VIII.
Since I have written of the varied work of pre
paring the ores, I
will now write of the various
methods of smelting them. Although those who
burn, roast and calcine
thing which is mixed or
combined with the metals;
and those who crush it with stamps take away
much;
and those who wash, screen and sort it, take away
still
more; yet they cannot remove all which con
ceals the metal from the
eye and renders it crude
and unformed. Wherefore smelting is necessary, for by this means earths,
solidified
juices, and stones are separated from the metals so that they
obtain
their proper colour and become pure, and may be of great use to
mankind
in many ways. When the ore is smelted, those things which
were mixed with the metal
before it was melted are driven forth, because
the metal is perfected
by fire in this manner. Since metalliferous ores
differ greatly amongst themselves, first as to
the metals which they con
tain, then as to the quantity of the
metal which is in them, and then by
the fact that some are rapidly
melted by fire and others slowly, there are,
therefore, many methods of
smelting. Constant practice has taught the
any one ore. Moreover, while sometimes there are many methods of
smelting the same
ore, by which an equal weight of metal is melted out, yet
one is done
at a greater cost and labour than the others. Ore is either melted
with a furnace or without one; if smelted with a
furnace the tap-hole is either
temporarily closed or always open, and
if smelted without a furnace, it is done
either in pots or in trenches. But in order to make this matter clearer, I will
describe each in
detail, beginning with the buildings and the furnaces.
A wall which will be called the “second wall” is constructed of
brick
or stone, two feet and as many palms thick, in order that it may
be strong
enough to bear the weight. It is built fifteen feet high, and its length depends
on the number of
furnaces which are put in the works; there are usually
six furnaces,
rarely more, and often less. There are three furnace walls, a
back one which is against the
“second” wall, and two side ones, of which I
will speak
later. These should be made of natural stone, as this is more
serviceable than
burnt bricks, because bricks soon become defective and
crumble away,
when the smelter or his deputy chips off the accretions which
adhere to
the walls when the ore is smelted. Natural stone resists injury
by the fire and lasts a long time,
especially that which is soft and devoid
of cracks; but, on the
contrary, that which is hard and has many cracks
is burst asunder by
the fire and destroyed. For this reason, furnaces which
are made of the latter are easily
weakened by the fire, and when the accretions
are chipped off they
crumble to pieces. The front furnace wall should be
made of brick, and there should be in
the lower part a mouth three palms
wide and one and a half feet high,
when the hearth is completed. A hole
slanting upward, three palms long, is made through the back
furnace wall, at
the height of a cubit, before the hearth has been
prepared; through this
hole and a hole one foot long in the
“second” wall—as the back of this wall
has an
arch—is inserted a pipe of iron or bronze, in which are fixed the
nozzles The whole of the front furnace wall is not more than five feet
high, so
that the ore may be conveniently put into the furnace, together with
those things which the master needs for his work of smelting. Both the side
walls of the furnace are six feet high, and the back one
seven feet, and they
are three palms thick. The interior of the furnace is five palms wide, six
palms and a digit
long, the width being measured by the space which lies
between the two
side walls, and the length by the space between the front and
the back
walls; however, the upper part of the furnace widens out somewhat.
There are two doors in the second wall if there are six furnaces, one
of
the doors being between the second and third furnaces and the other
between the fourth and fifth furnaces. They are a cubit wide and six feet
high, in order that the smelters may
not have mishaps in coming and going. It is necessary to have a door to the right of the first furnace, and
similarly
one to the left of the last, whether the wall is longer or
not. The second
wall is carried further when the rooms for the cupellation
furnaces, or any
other building, adjoin the rooms for the blast
furnaces, these buildings being
only divided by a partition. The smelter, and the ones who attend to the
first and the last furnaces,
if they wish to look at the bellows or to do anything
else, go out
through the doors at the end of the wall, and the other people go
through the other doors, which are the common ones. The furnaces are placed
at a distance of six feet from one another, in
order that the smelters and their
assistants may more easily sustain
the fierceness of the heat. Inasmuch as
the interior of each furnace is five palms wide and each is
six feet distant
from the other, and inasmuch as there is a space of
four feet three palms at
the right side of the first furnace and as
much at the left side of the last
furnace, and there are to be six
furnaces in one building, then it is necessary
to make the second wall
fifty-two feet long; because the total of the widths
of all of the
furnaces is seven and a half feet, the total of the spaces between
the
furnaces is thirty feet, the space on the outer sides of the first and last
furnaces is nine feet and two palms, and the thickness of the two
transverse
walls is five feet, which make a total measurement of
fifty-two feet.
Outside each furnace hearth there is a small pit full of powder which is
compressed by ramming, and in this manner is made the forehearth which
receives the metal flowing from the furnaces. Of this I will speak later.
Buried about a cubit under the forehearth and the hearth of the furnace
is a transverse water-tank, three feet long, three palms wide and a
cubit deep. It is made of stone or brick, with a stone cover, for if it were not covered,
the
heat would draw the moisture from below and the vapour might be
blown
into the hearth of the furnace as well as into the forehearth,
and would
dampen the blast. The moisture would vitiate the blast, and part of the
metal would be
absorbed and part would be mixed with the slags, and in
this manner the
melting would be greatly damaged. From each water-tank
is built a walled vent, to the same depth as the
tank, but six digits wide;
A—FURNACES. B—FOREHEARTHS.
side of the
wall, against which the furnace is built. At the end of this vent
there is an opening where the steam, into which
the water has been converted,
is exhausted through a copper or iron
tube or pipe. This method of making
the tank and the vent is much the best. Another kind has a similar vent
but a different tank, for it does not
lie transversely under the forehearth,
but lengthwise; it is two feet
and a palm long, and a foot and three palms
wide, and a foot and a palm
deep. This method of making tanks is not
condemned by us, as is the
construction of those tanks without a vent;
the latter, which have no
opening into the air through which the vapour may
discharge freely, are
indeed to be condemned.
A—FURNACES. B—FOREHEARTH. C—DOOR. D—WATER TANK.
E—STONE WHICH
COVERS IT. F—MATERIAL OF THE VENT WALLS.
G—STONE WHICH COVERS IT. H—PIPE
EXHALING THE VAPOUR.
Fifteen feet behind the second wall is constructed the first wall, thirteen
feet high. In both of these are fixed roof beams
from one another. As the second wall is two feet higher than the first wall,
recesses are
cut in the back of it two feet high, one foot wide, and a palm deep,
and in these recesses, as it were in mortises, are placed one end of
each of
the beams. Into these ends are mortised the bottoms of just as many posts;
these
posts are twenty-four feet high, three palms wide and thick, and from
the tops of the posts the same number of rafters stretch downward to
the
ends of the beams superimposed on the first wall; the upper ends of
the
rafters are mortised into the posts and the lower ends are mortised
into the
ends of the beams laid on the first wall; the rafters support
the roof,
which consists of burnt tiles. Each separate rafter is propped up by a
separate timber, which is a
cross-beam, and is joined to its post. Planks
close together are affixed to the posts above the furnaces; these
planks are
about two digits thick and a palm wide, and they, together
with the wicker
work interposed between the timbers, are covered with
lute so that there may
be no risk of fire to the timbers and
wicker-work. In this practical manner
is constructed the back part of the works,
which contains the bellows, their
frames, the mechanism for compressing
the bellows, and the instrument for
distending them, of all of which I
will speak hereafter.
In front of the furnaces is constructed the third long wall and likewise
the fourth. Both are nine feet high, but of the same length and thickness as
the
other two, the fourth being nine feet distant from the third; the
third
is twenty-one and a half feet from the second. At a distance of
twelve feet from the second wall, four posts seven and
a half feet high, a cubit
wide and thick, are set upon rock laid
underneath. Into the tops of the
posts the roof beam is mortised; this roof beam is
two feet and as many
palms longer than the distance between the second
and the fifth transverse
walls, in order that its ends may rest on the
transverse walls. If there should
not be so long a beam at hand, two are substituted for
it. As the length of
the long beam is as above, and as the posts are
equidistant, it is necessary
that the posts should be a distance of
nine feet, one palm, two and two-fifths
digits from each other, and the
end ones this distance from the transverse
walls. On this longitudinal beam and to the third and fourth walls are fixed
twelve secondary beams twenty-four feet long, one foot wide, three
palms
thick, and distant from each other three feet, one palm, and two
digits. In
these secondary beams, where they rest on the longitudinal beams, are
mortised
the ends of the same number of rafters as there are posts
which stand on the
second wall. The ends of the rafters do not reach to the tops of the posts,
but are
two feet away from them, that through this opening, which is like
the
open part of a forge, the furnaces can emit their fumes. In order that
the rafters should not fall down, they are supported
partly by iron rods,
which extend from each rafter to the opposite
post, and partly supported
by a few tie-beams, which in the same manner
extend from some rafters to
the posts opposite, and give them
stability. To these tie-beams, as well as
to the rafters which face the posts, a
number of boards, about two digits thick
and a palm wide, are fixed at
a distance of a palm from each other, and are In the secondary beams,
where they are laid on the fourth wall, are
mortised the lower ends of the
same number of rafters as those in a set
of raftersFrom
the third long wall these rafters are joined and tied to the ends
of the opposite
rafters, so that they may not slip, and besides they
are strengthened with
substructures which are made of cross and oblique
timbers. The rafters
support the roof.
THE FOUR LONG WALLS: A—FIRST. B—SECOND. C—THIRD.
D—FOURTH. THE
SEVEN TRANSVERSE WALLS: E—FIRST.
F—SECOND. G—THIRD. H—FOURTH.
I—FIFTH.
K—SIXTH. L—SEVENTH, OR MIDDLE.
In this manner the front part of the building is made, and is divided into
three parts; the first part is twelve feet wide and is under the hood,
which
consists of two walls, one vertical and one inclined. The second part is the
same number of feet wide and is for the reception
of the ore to be smelted,
the fluxes, the charcoal, and other things
which are needed by the smelter. The third part is nine feet wide and contains two separate rooms of equal
size, in one of which is the assay furnace, while the other contains
the metal
to be melted in the cupellation furnaces. It is thus necessary that in the
of which the first
is constructed from the upper end of the first long wall to
the upper
end of the second long wall; the second proceeds from the end
of this
to the end of the third long wall; the third likewise from this end of
the last extends to the end of the fourth long wall; the fourth leads
from
the lower end of the first long wall to the lower end of the
second long wall;
the fifth extends from the end of this to the end of
the third long wall; the
sixth extends from this last end to the end of
the fourth long wall; the
seventh divides into two parts the space
between the third and fourth long
walls.
To return to the back part of the building, in which, as I said, are the
bellows
ment for distending
them. Each bellows consists of a body and a head.
The body is composed of two “boards,” two bows, and two hides.
The
upper board is a palm thick, five feet and three palms long, and two
and a half
feet wide at the back part, where each of the sides is a
little curved, and it is
a cubit wide at the front part near the head. The whole of the body of the
bellows tapers toward the head. That which we now call the “board”
consists of two pieces of
pine, joined and glued together, and of two strips of
linden wood which
bind the edges of the board, these being seven digits
wide at the back,
and in front near the head of the bellows one and a half
digits wide. These strips are glued to the boards, so that there shall be less
damage
from the iron nails driven through the hide. There are some people
who do not surround the boards with strips, but
use boards only, which
are very thick. The upper board has an aperture and a handle; the
aperture is in the
middle of the board and is one foot three palms distant
from where the
board joins the head of the bellows, and is six digits long and
four
wide. The lid for this aperture is two palms and a digit long and wide,
and
three digits thick; toward the back of the lid is a little notch cut
into the surface so that it may be caught by the hand; a groove is cut
out
of the top of the front and sides, so that it may engage in
mouldings a palm
wide and three digits thick, which are also cut out in
a similar manner under
the edges. Now, when the lid is drawn forward the hole is closed, and
when drawn
back it is opened; the smelter opens the aperture a little so that
the
air may escape from the bellows through it, if he fears the hides might be
burst when the bellows are too vigorously and quickly inflated; he,
however,
closes the aperture if the hides are ruptured and the air
escapes. Others
perforate the upper board with two or three round holes in the
same place as
the rectangular one, and they insert plugs in them which
they draw out The wooden handle is seven palms long, or even longer,
in order that it
may extend outside; one-half of this handle, two palms
wide and one
thick, is glued to the end of the board and fastened with pegs
covered
with glue; the other half projects beyond the board, and is rounded
and
seven digits thick. Besides this, to the handle and to the board is fixed
a cleat two feet
long, as many palms wide and one palm thick, and to the under
side of
the same board, at a distance of three palms from the end, is fixed
another cleat two feet long, in order that the board may sustain the
force
of distension and compression; these two cleats are glued to the
board, and
are fastened to it with pegs covered with glue.
The lower bellows-board, like the upper, is made of two pieces of pine
and of two strips of linden wood, all glued together; it is of the same
width
and thickness as the upper board, but is a cubit longer, this
extension being
part of the head of which I have more to say a little
later. This lower bellows
board has an air-hole and an iron ring. The air-hole is about a cubit distant
from the posterior end, and it is
midway between the sides of the bellows
board, and is a foot long
and three palms wide; it is divided into equal
parts by a small rib
which forms part of the board, and is not cut from it;
this rib is a
palm long and one-third of a digit wide. The flap of the air
hole is a foot and three digits long, three
palms and as many digits wide;
it is a thin board covered with goat
skin, the hairy part of which is turned
toward the ground. There is fixed to one end of the flap, with small iron
nails, one-half
of a doubled piece of leather a palm wide and as long as the
flap is
wide; the other half of the leather, which is behind the flap, is twice
perforated, as is also the bellows-board, and these perforations are
seven
digits apart. Passing through these a string is tied on the under side of the
board;
and thus the flap when tied to the board does not fall away. In this
manner are made the flap and the air-hole, so when the bellows
are distended
the flap opens, when compressed it closes. At a distance of about a foot
beyond the air-hole a slightly elliptical
iron ring, two palms long and one
wide, is fastened by means of an iron
staple to the under part of the bellows
board; it is at a distance
of three palms from the back of the bellows. In
order that the lower bellows-board may remain stationary, a wooden
bolt is
driven into the ring, after it penetrates through the hole in
the transverse
supporting plank which forms part of the frame for the
bellows. There are
some who dispense with the ring and fasten the bellows-board
to the frame
with two iron screws something like nails.
The bows are placed between the two boards and are of the same length
as
the upper board. They are both made of four pieces of linden wood three
digits thick, of
which the two long ones are seven digits wide at the back and
two and a
half at the front; the third piece, which is at the back, is two
palms
wide. The ends of the bows are a little more than a digit thick, and are
mortised to the long pieces, and both having been bored through, wooden
pegs covered with glue are fixed in the holes; they are thus joined and
glued
to the long pieces. Each of the ends is bowed (
the long part of the bow,
whence its name “bow” originated. The fourth
the head of the bellows; the ends of
this piece are mortised into the ends
of the bow and are joined and
glued to them; its length without the tenons
is a foot, and its width a
palm and two digits. There are, besides, two other
very small pieces glued to the head of the
bellows and to the lower board,
and fastened to them by wooden pegs
covered with glue, and they are three
palms and two digits long, one
palm high, and a digit thick, one half being
slightly cut away. These pieces keep the ends of the bow away from the
hole in the
bellows-head, for if they were not there, the ends, forced inward
by
the great and frequent movement, would be broken.
The leather is of ox-hide or horse-hide, but that of the ox is far preferable
to that of the horse. Each of these hides, for there are two, is three and a
half feet wide
where they are joined at the back part of the bellows. A
long leathern thong is laid along each of the bellows-boards and each
of the
bows, and fastened by T-shaped iron nails five digits long; each
of the
horns of the nails is two and a half digits long and half a
digit wide. The
hide is attached to the bellows-boards by means of these nails, so
that a horn
of one nail almost touches the horn of the next; but it is
different with the
bows, for the hide is fastened to the back piece of
the bow by only two nails,
and to the two long pieces by four nails. In this practical manner they put
ten nails in one bow and the same
number in the other. Sometimes when the
smelter is afraid that the vigorous motion of the
bellows may pull or tear
the hide from the bows, he also fastens it
with little strips of pine by means of
another kind of nail, but these
strips cannot be fastened to the back pieces of
the bow, because these
are somewhat bent. Some people do not fix the
hide to the bellows-boards and bows by iron
nails, but by iron screws,
screwed at the same time through strips laid
over the hide. This method
of fastening the hide is less used than the other, although
there is no doubt
that it surpasses it in excellence.
Lastly, the head of the bellows, like the rest of the body, consists of two
boards, and of a nozzle besides. The upper board is one cubit long, one and a
half palms thick. The lower board is part of the whole of the lower bellows
board; it
is of the same length as the upper piece, but a palm and a digit
thick. From these two glued together is made the head, into which, when it
has
been perforated, the nozzle is fixed. The back part of the head, where
it is attached to the rest of the
bellows-body, is a cubit wide, but three palms
forward it becomes two
digits narrower. Afterward it is somewhat cut
away so that the front end may be rounded,
until it is two palms and as
many digits in diameter, at which point it
is bound with an iron ring three
digits wide.
The nozzle is a pipe made of a thin plate of iron; the diameter in front is
three digits, while at the back, where it is encased in the head of the
bellows,
it is a palm high and two palms wide. It thus gradually widens out, especially
at the back, in order that a
copious wind can penetrate into it; the whole
nozzle is three feet
long.
A—UPPER BELLOWS-BOARD. B—LOWER BELLOWS-BOARD. C—THE TWO
PIECES OF WOOD
OF WHICH EACH CONSISTS. D—POSTERIOR ARCHED PART OF
EACH. E—TAPERED FRONT
PART OF EACH. F—PIECES OF LINDEN
WOOD. G—APERTURE IN THE UPPER BOARD.
H—LID. I—LITTLE
MOULDINGS OF WOOD. K—HANDLE. L—CLEAT ON THE OUTSIDE.
THE
CLEAT INSIDE I AM NOT ABLE TO DEPICT. M—INTERIOR OF THE LOWER
BELLOWS
BOARD. N—PART OF THE HEAD. O—AIR-HOLE.
P—SUPPORTING BAR. Q—FLAP.
R—HIDE. S—THONG.
T—EXTERIOR OF THE LOWER BOARD. V—STAPLE. X—RING.
Y—BOW. Z—ITS LONG PIECES. AA—BACK PIECE OF THE BOW.
BB—THE BOWED
ENDS. CC—CROSSBAR DISTENDING THE BOW.
DD—THE TWO LITTLE PIECES.
EE—HIDE. FF—NAIL.
GG—HORN OF THE NAIL. HH—A SCREW. II—LONG THONG.
KK—HEAD. LL—ITS LOWER BOARD. MM—ITS UPPER BOARD.
NN—NOZZLE.
The upper bellows-board is joined to the head of the bellows in the
following way. An iron plate
is first fastened to the head at a distance of
three digits from the end; from
this plate there projects a piece three
digits long and two wide, curved
in a small circle. The other side has a similar plate.
Then in the same
part of the upper board are fixed two other iron
plates, distant two digits
from the edge, each of which are six digits
wide and seven long; in each
of these plates the middle part is cut
away for a little more than three
digits in length and for two in
depth, so that the curved part of the plates
on the head corresponding
to them may fit into this cut out part. From
both sides of each plate there project pieces, three digits long
and two
digits wide, similarly curved into small circles. A little iron pin is passed
through these curved pieces of the plates,
like a little axle, so that the upper
board of the bellows may turn
upon it. The little axle is six digits long and a
little more than a digit thick,
and a small groove is cut out of the upper
board, where the plates are
fastened to it, in such a manner that the little axle
when fixed to the
plates may not fall out. Both plates fastened to the
bellows-board are affixed by four iron
nails, of which the heads are on the
inner part of the board, whereas
the points, clinched at the top, are
transformed into heads, so to
speak. Each of the other plates is fastened
to the head of the bellows by means
of a nail with a wide head, and by two
other nails of which the heads
are on the edge of the bellows-head. Midway
between the two plates on the bellows-board there remains a space
two
palms wide, which is covered by an iron plate fastened to the board
by
little nails; and another plate corresponding to this is fastened to
the head
between the other two plates; they are two palms and the same
number
of digits wide.
The hide is common to the head as to all the other parts of the body;
the plates are covered with it, as well as the front part of the upper
bellows
board, and both the bows and the back of the head of the
bellows, so that the
wind may not escape from that part of the bellows. It is three palms and as
many digits wide, and long enough to extend
from one of the sides of the
lower board over the back of the upper; it
is fastened by many T-headed
nails on one side to the upper board, and
on the other side to the head of
the bellows, and both ends are
fastened to the lower bellows-board.
In the above manner the bellows is made.
As two are required for each
furnace, it is necessary to have twelve
bellows, if there are to be six furnaces
in one works.
Now it is time to describe their framework.
First, two sills a little
shorter than the furnace wall are placed on
the ground. The front one of
these is three palms wide and thick, and the back one
three palms and two
digits. The front one is two feet distant from the back wall of the furnace, and
the back one is six feet three palms distant from the front one. They are set into
the earth, that they may remain firm; there are some
who accomplish this by
means of pegs which, through several holes,
penetrate deeply into the ground.
Then twelve short posts are erected, whose lower ends are mortised into
the sill that is near the back of the furnace wall; these posts are two
feet
high, exclusive of the tenons, and are three palms and the same
number of
digits wide, and two palms thick. A slot one and a half palms wide is cut
through them, beginning two
palms from the bottom and extending for a
height of three palms. All the posts are not placed at the same intervals, the
first being at a
distance of three feet five digits from the second, and likewise
the
third from the fourth, but the second is two feet one palm and three
digits from the third; the intervals between the other posts are
arranged in
the same manner, equal and unequal, of which each four
pertain to two
furnaces. The upper ends of these posts are mortised into a transverse
beam which
is twelve feet, two palms, and three digits long, and projects
five
digits beyond the first post and to the same distance beyond the fourth;
it is two palms and the same number of digits wide, and two palms
thick. Since each separate transverse beam supports four bellows, it is necessary to
have three of them.
Behind the twelve short posts the same number of higher posts are
erected, of which each has the middle part of the lower end cut out, so
that
its two resulting lower ends are mortised into the back sill;
these posts,
exclusive of the tenons, are twelve feet and two palms
high, and are five palms
wide and two palms thick. They are cut out from the bottom upward, the
slot being four feet and
five digits high and six digits wide. The upper ends of
these posts are mortised into a long beam imposed upon
them; this long
beam is placed close under the timbers which extend
from the wall at the
back of the furnace to the first long wall; the
beam is three palms wide
and two palms thick, and forty-three feet
long. If such a long one is
not at hand, two or three may be substituted for
it, which when joined together
make up that length. These higher posts are not placed at equal distances,
but the first is
at a distance of two feet three palms one digit from the second,
and
the third is at the same distance from the fourth; while the second is at a
distance of one foot three palms and the same number of digits from the
third, and in the same manner the rest of the posts are arranged at
equal
and unequal intervals. Moreover, there is in every post, where it faces the
shorter post, a
mortise at a foot and a digit above the slot; in these mortises
of the
four posts is tenoned a timber which itself has four mortises. Tenons
are enclosed in mortises in order that they may be better joined,
and they
are transfixed with wooden pins. This timber is thirteen feet three palms
one digit long, and it projects
beyond the first post a distance of two palms
and two digits, and to
the same number of palms and digits beyond the
fourth post. It is two palms and as many digits wide, and also two palms
thick. As there are twelve posts it is necessary to have three timbers of this
kind.
On each of these timbers, and on each of the cross-beams which are laid
upon the shorter posts, are placed four planks, each nine feet long,
two palms
three digits wide, and two palms one digit thick. The first plank is five feet
one palm one digit distant from the second,
at the front as well as at the back. The third is at the
same distance from the fourth, but the second is one
foot and three digits
distant from the third. In the same manner the rest of the eight planks are
arranged at
intervals, the fifth from the sixth and the seventh from the eighth
are
at the same distances as the first from the second and the third from the
fourth; the sixth is at the same distance from the seventh as the
second
from the third.
Two planks support one transverse plank six feet long, one foot wide, one
palm thick, placed at a distance of three feet and two palms from the
back
posts. When there are six of these supporting planks, on each separate one
are
placed two bellows; the lower bellows-boards project a palm beyond
them. From each of the bellows-boards an iron ring descends through a hole
in
its supporting plank, and a wooden peg is driven into the ring, so that the
bellows-board may remain stationary, as I stated above.
The two bellows communicate, each by its own plank, to the back of a
copper pipe in which are set both of the nozzles, and their ends are
tightly
A—FRONT SILL. B—BACK SILL. C—FRONT POSTS. D—THEIR
SLOTS. E—BEAM
IMPOSED UPON THEM. F—HIGHER POSTS.
G—THEIR SLOTS. H—BEAM IMPOSED UPON
THEM. I—TIMBER
JOINED IN THE MORTISES OF THE POSTS. K—PLANKS. L—TRANSVERSE
SUPPORTING PLANKS. M—THE HOLES IN THEM. N—PIPE. O—ITS
FRONT END. P—ITS
REAR END.The pipe is made of a rolled copper or iron plate, a foot and
two palms
and the same number of digits long; the plate is half a digit
thick,
but a digit thick at the back. The interior of the pipe is three digits
wide, and two and a half digits
high in the front, for it is not absolutely round;
and at the back it
is a foot and two palms and three digits in diameter. The
plate from which the pipe is made is not entirely joined up, but at
the front
there is left a crack half a digit wide, increasing at the
back to three digits. This pipe is placed in the hole in the furnace, which, as I said, was in the
middle of the wall and the arch. The nozzles of the bellows, placed in this
pipe, are a distance of five
digits from its front end.
The levers are of the same number as the bellows, and when depressed
by
the cams of the long axle they compress the bellows. These levers
are eight feet three palms long, one palm wide and thick,
and the ends are
inserted in the slots of the posts; they project
beyond the front posts to a
distance of two palms, and the same
distance beyond the back posts in order
that each may have its end
depressed by its two cams on the axle. The
cams not only penetrate into the slots of the back posts, but
project three
digits beyond them. An iron pin is set in round holes made through both
sides of the slot of
each front post, at three palms and as many digits from the
bottom; the
pin penetrates the lever, which turns about it when depressed
or
raised. The back of the lever for the length of a cubit is a palm and a
digit
wider than the rest, and is perforated; in this hole is engaged a bar
six feet and two palms long, three digits wide, and about one and
one-half
digits thick; it is somewhat hooked at the upper end, and
approaches the
handle of the bellows. Under the lever there is a nail, which penetrates
through a hole in the
bar, so that the lever and bar may move together. The
bar is perforated in the upper end at a distance of six digits from
the top;
this hole is two palms long and a digit wide, and in it is
engaged the hook of
an iron implement which is a digit thick. At the upper part this implement
has either a round or square opening,
like a link, and at the lower end is
hooked; the link is two digits
high and wide and the hook is three digits long;
the middle part
between the link and the hook is three palms and two
digits long. The link of this implement engages either the handle of the
bellows, or
else a large ring which does engage it. This iron ring is a digit thick,
two palms wide on the inside of the
upper part, and two digits in the
lower part, and this iron ring, not
unlike the first one, engages the
handle of the bellows. The iron ring either has its narrower part turned
upward, and in it is
engaged the ring of another iron implement, similar
to the first, whose
hook, extending upward, grips the rope fastened to the
iron ring
holding the end of the second lever, of which I will speak
presently;
or else the iron ring grips this lever, and then in its hook is
engaged
the ring of the other implement whose ring engages the handle of the
bellows, and in this case the rope is dispensed with.
Resting on beams fixed in the two walls is a longitudinal beam, at a
distance of four and a half feet from the back posts; it is two palms
wide,
A—LEVER WHICH WHEN DEPRESSED BY MEANS OF A CAM COMPRESSES THE BELLOWS.
B—SLOTS THROUGH THE POSTS. C—BAR. D—IRON IMPLEMENT
WITH A RECTANGULAR
LINK. E—IRON INSTRUMENT WITH ROUND RING.
F—HANDLE OF BELLOWS. G—UPPER
POST. H—UPPER LEVER.
I—BOX WITH EQUAL SIDES. K—BOX NARROW AT THE
BOTTOM.
L—PEGS DRIVEN INTO THE UPPER LEVER.
one and a half palms thick. There are mortised into this longitudinal beam
the lower ends of upper
posts three palms wide and two thick, which are six
feet two palms
high, exclusive of their tenons. The upper ends of these
posts are mortised into an upper longitudinal
beam, which lies close under
the rafters of the building; this upper
longitudinal beam is two palms
wide and one thick. The upper posts have a slot cut out upward from a
point two feet from
the bottom, and the slot is two feet high and six digits
wide. Through these upper posts a round hole is bored from one side to
the
other at a point three feet one palm from the bottom, and a small iron axle
penetrates through the hole and is fastened there. Around this small iron
axle turns the second lever when it is depressed
and raised. This lever is
eight feet long, and its other end is three digits wider
than the rest of the
lever; at this widest point is a hole two digits
wide and three high, in which
is fixed an iron ring, to which is tied
the rope I have mentioned; it is five
palms long, its upper loop is two
palms and as many digits wide, and the This half of the second lever, the end
of which I have just mentioned,
is three palms high and one wide; it projects
three feet beyond the
slot of the post on which it turns; the other end, which
faces the back
wall of the furnaces, is one foot and a palm high and a foot wide.
On this part of the lever stands and is fixed a box three and a half feet
long, one foot and one palm wide, and half a foot deep; but these
measure
ments vary; sometimes the bottom of this box is narrower,
sometimes
equal in width to the top. In either case, it is filled with stones and earth
to make it heavy, but
the smelters have to be on their guard and
make provision against the
stones falling out, owing to the constant
motion; this is prevented by
means of an iron band which is placed over
the top, both ends being
wedge-shaped and driven into the lever so that the
stones can be held
in. Some people, in place of the box, drive four or more
pegs into the lever
and put mud between them, the required amount being
added to the weight
or taken away from it.
There remains to be considered the method of using this machine.
The
lower lever, being depressed by the cams, compresses the bellows,
and the
compression drives the air through the nozzle. Then the weight of the box
on the other end of the upper lever raises
the upper bellows-board, and the
air is drawn in, entering through the
air-hole.
The machine whose cams depress the lower lever is made as follows.
First there is an axle, on whose end outside the building is a water-wheel;
at the other end, which is inside the building, is a drum made of
rundles. This drum is composed of two double hubs, a foot apart, which are five digits
thick, the radius all round being a foot and two digits; but they are
double,
because each hub is composed of two discs, equally thick,
fastened together
with wooden pegs glued in. These hubs are sometimes covered above and
around by iron plates. The rundles are thirty in number, a foot and two
palms and the same
number of digits long, with each end fastened into a hub;
they are
rounded, three digits in diameter, and the same number of digits
apart. In this practical manner is made the drum composed of rundles.
There is a toothed wheel, two palms and a digit thick, on the end
of
another axle; this wheel is composed of a double discThe inner disc
is composed of four segments a palm thick, everywhere two
palms and a
digit wide. The outer disc, like the inner, is made of four segments, and is
a palm
and a digit thick; it is not equally wide, but where the head of the
spokes are inserted it is a foot and a palm and digit wide, while on
each side
of the spokes it becomes a little narrower, until the
narrowest part is only
two palms and the same number of digits wide. The outer segments are joined
to the inner ones in such a manner that,
on the one hand, an outer segment
ends in the middle of an inner one,
and, on the other hand, the ends of the
inner segments are joined in
the middle of the outer ones; there is no doubt
that by this kind of
joining the wheel is made stronger. The outer segments
are fastened to the inner by means of a large number
of wooden pegs. Each
A—AXLE. B—WATER-WHEEL. C—DRUM COMPOSED OF RUNDLES.
D—OTHER AXLE.
E—TOOTHED WHEEL. F—ITS SPOKES.
G—ITS SEGMENTS. H—ITS TEETH. I—CAMS
OF THE
AXLE.
segment, measured over its round back, is four feet and three
palms long. There are four spokes, each two palms wide and a palm and a digit thick;
their
length, excluding the tenons, being two feet and three digits. One end of the
spoke is mortised into the axle, where it is firmly
fastened with pegs; the
wide part of the other end, in the shape of a
triangle, is mortised into the
outer segment opposite it, keeping the
shape of the same as far as the segment
ascends. They also are joined together with wooden pegs glued in, and these
pegs
are driven into the spokes under the inner disc. The parts of the spokes
in the shape of the triangle are on the inside;
the outer part is simple. This
triangle has two sides equal, the erect ones as is evident, which
are a palm
long; the lower side is not of the same length, but is five
digits long, and a
mortise of the same shape is cut out of the
segments. The wheel has sixty
teeth, since it is necessary that the rundle drum
should revolve twice while
the toothed wheel revolves once. The teeth are a foot long, and project one
palm from the inner disc of
the wheel, and three digits from the outer disc;
that
they should be three digits apart, as were the rundles.
The axle should have a thickness in proportion to the spokes and the
segments. As it has two cams to depress each of the levers, it is necessary that
it should have twenty-four cams, which project beyond it a foot and a
palm and
a digit. The cams are of almost semicircular shape, of which the widest part is
three palms and a digit wide, and they are a palm thick; they are
distributed according to the four sides of the axle, on the upper, the
lower
and the two lateral sides. The axle has twelve holes, of which the first
penetrates through from
the upper side to the lower, the second from one
lateral side to the
other; the first hole is four feet two palms distant from
the second;
each alternate one of these holes is made in the same direc
tion,
and they are arranged at equal intervals. Each single cam must
be opposite another; the first is inserted into the
upper part of the first
hole, the second into the lower part of the
same hole, and so fixed by
pegs that they do not fall out; the third
cam is inserted into that part
of the second hole which is on the right
side, and the fourth into that
part on the left. In like manner all the cams are inserted into the consecutive
holes, for
which reason it happens that the cams depress the levers of the
A—CHARCOAL. B—MORTAR-BOX. C—STAMPS.
Finally we must not omit to state that this is only one
of many such
axles having cams and a water-wheel.
I have arrived thus far with many words, and yet it is not unseasonable
that I have in this place pursued the subject minutely, since the
smelting of all
the metals, to which I am about to proceed, could not
be undertaken without
it.
The ores of gold, silver, copper, and lead, are smelted in a furnace by
four different methods. The first method is for the rich ores of gold or silver,
the second for
the mediocre ores, the third for the poor ores, and the fourth
method
is for those ores which contain copper or lead, whether they contain
precious metals or are wanting in them. The smelting of the first ores is
performed in the furnace of which the
tap-hole is intermittently closed; the
other three ores are melted in
furnaces of which the tap-holes are always
open.
First, I will speak of the manner in which the furnaces are prepared for
the smelting of the ores, and of the first method of smelting. The powder
from which the hearth and forehearth should be made is
composed of char
coal and earth (clay?). The charcoal is crushed by
the stamps in a mortar
box, the front of which is closed by a board
at the top, while the charcoal,
A—TUB. B—SIEVE. C—RODS. D—BENCH-FRAME.
not shod with iron, but are made entirely of
wood, although at the lower
part they are bound round at the wide part
by an iron band.
The powder into which the charcoal is crushed is thrown on to a sieve
whose bottom consists of interwoven withes of wood. The sieve is drawn
backward and forward over two wooden or iron rods
placed in a triangular
position on a tub, or over a bench-frame set on
the floor of the building;
the powder which falls into the tub or on to
the floor is of suitable size,
but the pieces of small charcoal which
remain in the sieve are emptied out
and thrown back under the
stamps.
When the earth is dug up it is first exposed to the sun that it may dry.
Later on it is thrown with a shovel on to a screen—set up obliquely and
supported by poles,—made of thick, loosely woven hazel withes,
and in this
way the fine earth and its small lumps pass through the
holes of the screen, but
the clods and stones do not pass through, but
run down to the ground. The
earth which passes through the screen is conveyed in a two-wheeled
cart to
the works and there sifted. This sieve, which is not dissimilar to the one
A—SCREEN. B—POLES. C—SHOVEL. D—TWO-WHEELED CART.
E—HAND-SIEVE.
F—NARROW BOARDS. G—BOX. H—COVERED
PIT.
equal length placed over a long box; the powder
which falls through the
sieve into the box is suitable for the mixture;
the lumps that remain in the
sieve are thrown away by some people, but
by others they are placed under
the stamps. This powdered earth is mixed with powdered charcoal, moist
ened, and
thrown into a pit, and in order that it may remain good for a long
time, the pit is covered up with boards so that the mixture may not
become contaminated.
They take two parts of pulverised charcoal and one part of powdered
earth, and mix them well together with a rake; the mixture is moistened
by
pouring water over it so that it may easily be made into shapes
resembling
snowballs; if the powder be light it is moistened with more
water, if heavy
with less. The interior of the new furnace is lined with lute, so that the
cracks
in the walls, if there are any, may be filled up, but especially in order
to preserve the rock from injury by fire. In old furnaces in which ore has
been melted, as soon as the rocks have
cooled the assistant chips away, with
a spatula, the accretions which
adhere to the walls, and then breaks them
up with an iron hoe or a rake
with five teeth. The cracks of the furnace are
first filled in with fragments of rock or
brick, which he does by passing his
hand into the furnace through its
mouth, or else, having placed a ladder against
it, he mounts by the
rungs to the upper open part of the furnace. To the
upper part of the ladder a board is fastened that he may lean and
recline
against it. Then standing on the same ladder, with a wooden spatula, he
smears the
furnace walls over with lute; this spatula is four feet long, a digit
thick, and for a foot upward from the bottom it is a palm wide, or even
wider, generally two and a half digits. He spreads the lute equally over the
inner walls of the furnace. The mouth of the copper pipe
trude from the lute, lest sows
melting, for
the furnace bellows could not force a blast through them. Then
the same assistant throws a little powdered charcoal into the pit
of the fore
hearth and sprinkles it with pulverised earth. Afterward, with a bucket
he pours water into it and sweeps this all over
the forehearth pit, and with the
broom drives the turbid water into the
furnace hearth and likewise sweeps
it out. Next he throws the mixed and moistened powder into the furnace,
and then
a second time mounting the steps of the ladder, he introduces the
rammer into the furnace and pounds the powder so that the hearth is
made
solid. The rammer is rounded and three palms long; at the bottom it is five
digits in diameter, at the top three and a half, therefore it is made
in the form
of a truncated cone; the handle of the rammer is round and
five feet long and
A—FURNACE. B—LADDER. C—BOARD FIXED TO IT. D—HOE.
E—FIVE
TOOTHED RAKE. F—WOODEN SPATULA. G—BROOM.
H—RAMMER. I—RAMMER, SAME
DIAMETER. K—TWO WOODEN
SPATULAS. L—CURVED BLADE. M—BRONZE RAMMER.
N—ANOTHER
BRONZE RAMMER. O—WIDE SPATULA. P—ROD. Q—WICKER BASKET.
R—TWO BUCKETS OF LEATHER IN WHICH WATER IS CARRIED FOR PUTTING
OUT A CON
FLAGRATION, SHOULD THE
IS SQUIRTED OUT. T—TWO HOOKS. V—RAKE.
X—WORKMAN BEATING THE CLAY WITH
AN IRON IMPLEMENT.
two and a
half digits thick; the upper part of the rammer, where the handle
is
inserted, is bound with an iron band two digits wide. There are some who,
instead, use two rounded rammers three and a half
digits in diameter, the
same at the bottom as at the top. Some people prefer two wooden
spatulas, or a rammer spatula.
In a similar manner, mixed and moistened powder is thrown and pounded
with a rammer in the forehearth pit, which is outside the furnace. When
this is nearly completed, powder is again put in, and pushed with
the rammer
up toward the protruding copper pipe, so that from a point a
digit under the
mouth of the copper pipe the hearth slopes down into
the crucible of the fore
hearth,The same is repeated until the
blade; this blade is
of iron, two palms and as many digits long, three digits
wide, blunt at
the top and sharp at the bottom. The crucible of the fore
hearth must be round, a foot in diameter
and two palms deep if it has to
contain a
in diameter and two palms deep like the other. When the forehearth has
been hollowed out it is pounded with a round
bronze rammer. This is
five digits high and the same in diameter, having a curved round
handle
one and a half digits thick; or else another bronze rammer is
used, which
is fashioned in the shape of a cone, truncated at the top,
on which is
imposed another cut away at the bottom, so that the middle
part of the
rammer may be grasped by the hand; this is six digits high,
and five digits
in diameter at the lower end and four at the top. Some use in its place a
wooden spatula two and a half palms wide at the
lower end and one palm
thick.
The assistant, having prepared the forehearth, returns to the furnace and
besmears both sides as well as the top of the mouth with simple lute. In the
lower part of the mouth he places lute that has been dipped in
charcoal
dust, to guard against the risk of the lute attracting to
itself the powder
of the hearth and vitiating it. Next he lays in the mouth of the furnace a
straight round rod three
quarters of a foot long and three digits in diameter. Afterward he places a piece of charcoal on the lute, of the same length and
width as the mouth, so that it is entirely closed up; if there be not
at hand
one piece of charcoal so large, he takes two instead. When the mouth is thus
closed up, he throws into the furnace a wicker
basket full of charcoal, and in
order that the piece of charcoal with
which the mouth of the furnace is closed
should not then fall out, the
master holds it in with his hand. The pieces
of charcoal which are thrown into the furnace should be of
medium size, for
if they are large they impede the blast of the bellows
and prevent it from
blowing through the tap-hole of the furnace into
the forehearth to heat it. Then the master covers over the charcoal, placed at the mouth of the furnace,
with lute and extracts the wooden rod, and thus the furnace is
prepared. Afterward the assistant throws four or five larger baskets full of charcoal
into the furnace, filling it right up; he also throws a little charcoal
into the forehearth, and places glowing coals upon it in order that it
may
be kindled, but in order that the flames of this fire should not
enter through
the tap-hole of the furnace and fire the charcoal inside,
he covers the tap-hole
with lute or closes it with fragments of
pottery. Some do not warm the
forehearth the same evening, but place large
charcoals round the edge of it, one
leaning on the other; those who
follow the first method sweep out the
forehearth in the morning, and
clean out the little pieces of charcoal and
cinders, while those who
follow the latter method take, early in the morning,
burning
firebrands, which have been prepared by the watchman of the works,
and
place them on the charcoal.
At the fourth hour the master begins his work.
He first inserts a
small piece of glowing coal into the furnace, through
the bronze nozzle-pipe
of half an hour the
forehearth, as well as the hearth, becomes warmed, and
of course more
quickly if on the preceding day ores have been smelted in the
same
furnace, but if not then it warms more slowly. If the hearth and
forehearth are not warmed before the ore to be smelted
is thrown in, the furnace
is injured and the metals lost; or if the
powder from which both are made
is damp in summer or frozen in winter,
they will be cracked, and, giving
out a sound like thunder, they will
blow out the metals and other substances
with great peril to the
workmen. After the furnace has been warmed, the
master throws in slags, and
these, when melted, flow out through the tap
hole into the
forehearth. Then he closes up the tap-hole at once with
mixed lute and charcoal
dust; this plug he fastens with his hand to a
round wooden rammer that
is five digits thick, two palms high, with a handle
three feet long. The smelter extracts the slags from the forehearth with a
hooked bar; if
the ore to be smelted is rich in gold or silver he puts into the
forehearth a
because the former requires much lead, the latter little; he
immediately
throws burning firebrands on to the lead so that it melts. Afterward he
performs everything according to the usual manner and
order, whereby he
first throws into the furnace as many cakes melted
from pyrites
requires
to smelt the ore; then he puts in two wicker baskets full of ore
with
litharge and hearth-lead
second order, all mixed
together; then one wicker basket full of charcoal,
and lastly the
slags. The furnace now being filled with all the things I
have mentioned, the
ore is slowly smelted; he does not put too much of it
against the back
wall of the furnace, lest sows should form around the nozzles
of the
bellows and the blast be impeded and the fire burn less fiercely.
This, indeed, is the custom of many most excellent smelters, who know
how to govern the four elementsThey combine in right proportion the
ores, which are part earth, placing
no more than is suitable in the furnaces;
they pour in the needful
quantity of water; they moderate with skill the air
from the bellows;
they throw the ore into that part of the fire which burns
fiercely. The master sprinkles water into each part of the furnace to dampen
the
charcoal slightly, so that the minute parts of ore may adhere to it,
which otherwise the blast of the bellows and the force of the fire
would agitate
and blow away with the fumes. But as the nature of the ores to be smelted
varies, the smelters have to
arrange the hearth now high, now low, and to
place the pipe in which
the nozzles of the bellows are inserted sometimes on a
great and
sometimes at a slight angle, so that the blast of the bellows may
For those ores
which heat and fuse easily, a low hearth is necessary for
the work of the
smelters, and the pipe must be placed at a gentle angle
to produce a mild
blast from the bellows. On the contrary, those ores that heat and fuse
slowly must have a high
hearth, and the pipe must be placed at a steep incline
in order to blow
a strong blast of the bellows, and it is necessary, for this
kind of
ore, to have a very hot furnace in which slags, or cakes melted from
pyrites, or stones which melt easily in the fire
ore
should not settle in the hearth of the furnace and obstruct and choke up
the tap-hole, as the minute metallic particles that have been washed
from
the ores are wont to do. Large bellows have wide nozzles, for if they were
narrow the copious and
strong blast would be too much compressed and too
acutely blown into
the furnace, and then the melted material would be
chilled, and would
form sows around the nozzle, and thus obstruct the opening
into the
furnace, which would cause great damage to the proprietors'
property. If the ores agglomerate and do not fuse, the smelter, mounting
on the
ladder placed against the side of the furnace, divides the charge with
a pointed or hooked bar, which he also pushes down into the pipe in
dislodges the ore and the sows from around it.
After a quarter of an hour, when the lead which the assistant has placed
in the forehearth is melted, the master opens the tap-hole of the
furnace
with a tapping-bar. This bar is made of iron, is three and a half feet long,
the forward end
pointed and a little curved, and the back end hollow so that
into it
may be inserted a wooden handle, which is three feet long and thick
enough to be well grasped by the hand. The slag first flows from the furnace
into the forehearth, and in it are
stones mixed with metal or with the metal
adhering to them partly
altered, the slag also containing earth and solidified
juices. After this the material from the melted pyrites flows out, and then the
molten lead contained in the forehearth absorbs the gold and silver. When
that which has run out has stood for some time in the forehearth,
in order
to be able to separate one from the other, the master first
either skims off
the slags with the hooked bar or else lifts them off
with an iron fork; the
slags, as they are very light, float on the top. He next draws off the cakes of
melted pyrites, which as they are of
medium weight hold the middle place;
he leaves in the forehearth the
alloy of gold or silver with the lead, for these
being the heaviest,
sink to the bottom. As, however, there is a difference
lowest much, he puts
these away separately, each in its own place, in
order that to each
heap, when it is re-smelted, he may add the proper
fluxes, and can put
in as much lead as is demanded for the metal in the
slag; when the slag
is re-melted, if it emits much odour, there is some
metal in it; if it
emits no odour, then it contains none. He puts the cakes
of melted pyrites away separately, as they were
nearest in the forehearth to
the metal, and contain a little more of it
than the slags; from all these
cakes a conical mound is built up, by
always placing the widest of them
at the bottom. The hooked bar has a hook on the end, hence its name;
otherwise it is
similar to other bars.
Afterward the master closes up the tap-hole and fills the furnace with
the same materials I described above, and again, the ores having been
melted,
he opens the tap-hole, and with a hooked bar extracts the slags
and the cakes
melted from pyrites, which have run down into the
forehearth. He repeats
the same operation until a certain and definite part of the
ore has been
smelted, and the day's work is at an end; if the ore was
rich the work is
finished in eight hours; if poor, it takes a longer
time. But if the ore was
so rich as to be smelted in less than eight hours,
another operation is in the
meanwhile combined with the first, and both
are performed in the space of ten
hours. When all the ore has been smelted, he throws into the furnace a
basket
full of litharge or hearth-lead, so that the metal which has remained
in the accretions may run out with these when melted. When he has finally
drawn out of the forehearth the slags and the cakes
melted from pyrites,
he takes out, with a ladle, the lead alloyed with
gold or silver and pours it into
little iron or copper pans, three
palms wide and as many digits deep, but
first lined on the inside with
lute and dried by warming, lest the glowing molten
substances should
break through. The iron ladle is two palms wide, and in
other respects it is similar to
the others, all of which have a sufficiently long
iron shaft, so that
the fire should not burn the wooden part of the handle. When the alloy has been poured out of the forehearth, the smelter foreman
and the mine captain weigh the cakes.
Then the master breaks out the whole of the mouth of the furnace with a
crowbar, and with that other hooked bar, the rabble and the
five-toothed rake,
he extracts the accretions and the charcoal. This crowbar is not unlike
the other hooked one, but larger and wider;
the handle of the rabble is six feet
long and is half of iron and half
of wood. The furnace having cooled, the
master chips off the accretions clinging
to the walls with a rectangular
spatula six digits long, a palm broad,
and sharp on the front edge; it has
a round handle four feet long, half
of it being of iron and half of wood. This
is the first method of smelting ores.
Because they generally consist of unequal constituents, some of which melt
rapidly and others slowly, the ores rich in gold and silver cannot be
smelted as
rapidly or as easily by the other methods as they can by the
first method, for
three important reasons. The first reason is that, as often as the closed
tap-hole of the furnace
is opened with a tapping-bar, so often can the
A, B, C—THREE FURNACES. AT THE FIRST STANDS THE SMELTER, WHO WITH A
LADLE
POURS THE ALLOY OUT OF THE FOREHEARTH INTO THE MOULDS.
D—FOREHEARTH.
E—LADLE. F—MOULDS. G—ROUND WOODEN
RAMMER. H—TAPPING-BAR. AT THE
SECOND FURNACE STANDS THE SMELTER.
WHO OPENS THE TAP-HOLE WITH HIS TAPPING-BAR.
whether it is flaming in scattered bits, and not uniting in one mass;
in the
first case the ore is smelting too slowly and not without great
expense; in
the second case the metal mixes with the slag which flows
out of the
furnace into the forehearth, wherefore there is the expense
of melting it again;
in the third case, the metal is consumed by the
violence of the fire. Each of
these evils has its remedy; if the ore melts slowly or does not
come together,
it is necessary to add some amount of fluxes which melt
the ore; or if they
melt too readily, to decrease the amount.
The second reason is that each time that the furnace is opened with a
tapping-bar, it flows out into the forehearth, and the smelter is able
to test
the alloy of gold and lead or of silver with lead, which is
called When the tap-hole is opened the second or third time, this test shows us
whether the alloy of gold or silver has become richer, or whether the
lead is
too debilitated and wanting in strength to absorb any more gold
or silver. If
it has become richer, some portion of lead added to it should renew
its
strength; if it has not become richer, it is poured out of the
forehearth that
it may be replaced with fresh lead.
The third reason is that if the tap-hole of the furnace is always open
when the ore and other things are being smelted, the fluxes, which are
easily
melted, run out of the furnace before the rich gold and silver
ores, for these
are sometimes of a kind that oppose and resist melting
by the fire for a longer
period. It follows in this case, that some part of the ore is either
con
sumed or is mixed with the accretions, and as a result little
lumps of ore
not yet melted are now and then found in the accretions. Therefore when
these ores are being smelted, the tap-hole of the furnace
should be closed
for a time, as it is necessary to heat and mix the ore
and the fluxes at the
same time; since the fluxes fuse more rapidly
than the ore, when the
molten fluxes are held in the furnace, they thus
melt the ore which does not
readily fuse or mix with the lead. The lead absorbs the gold or silver, just
as tin or lead when melted in
the forehearth absorbs the other unmelted
metal which has been thrown
into it. But if the molten matter is poured
upon that which is not molten, it
runs off on all sides and consequently does
not melt it. It follows from all this that ores rich in gold or silver, when put
into
a furnace with its tap-hole always open, cannot for that reason be smelted
so successfully as in one where the tap-hole is closed for a time, so
that during
this time the ore may be melted by the molten fluxes. Afterward, when the
tap-hole has been opened, they flow into the
forehearth and mix there with
the molten lead. This method of smelting the ores is used by us and by the
Bohemians.
The three remaining methods of smelting ores are similar to each other
in that the tap-holes of the furnaces always remain open, so that the
molten
metals may continually run out. They differ greatly from each other,
A, B—TWO FURNACES. C—FOREHEARTHS. D—DIPPING-POT. THE
SMELTER STANDING
BY THE FIRST FURNACE DRAWS OFF THE SLAGS WITH A HOOKED
BAR. E—HOOKED BAR.
F—SLAGS. G—THE ASSISTANT DRAWING A
BUCKET OF WATER WHICH HE POURS OVER THE
GLOWING SLAGS TO QUENCH THEM.
H—BASKET MADE OF TWIGS OF WOOD INTERTWINED.
I—RABBLE.
K—ORE TO BE SMELTED. THE MASTER STANDS AT THE OTHER FURNACE
narrower than that of the third,
and besides it is invisible and concealed. It easily discharges into the forehearth, which is one and a half feet higher
than the floor of the building, in order that below it to the left a
dipping-pot
can be made. When the forehearth is nearly full of the slags, which well up
from the
invisible tap-hole of the furnace, they are skimmed off from the top
with a hooked bar; then the alloy of gold or silver with lead and the
melted
pyrites, being uncovered, flow into the dipping-pot, and the
latter are made into
cakes; these cakes are broken and thrown back into
the furnace so that all
their metal may be smelted out. The alloy is poured into little iron moulds.
The smelter, besides lead and cognate things, uses fluxes which combine
with the ore, of which I gave a sufficient account in Book VII. The metals
which are melted from ores that fuse readily in the fire, are
profitable because
they are smelted in a short time, while those which
are difficult to fuse are
not as profitable, because they take a long
time. When fluxes remain in the
furnace and do not melt, they are not
suitable; for this reason, accretions and
slags are the most convenient
for smelting, because they melt quickly. It is
necessary to have an industrious and experienced smelter, who in
the first
place takes care not to put into the furnace more ores mixed
with fluxes than
it can accommodate.
The powder out of which this furnace hearth and the adjoining
fore
hearth and the dipping-pot are usually made, consists mostly
of equal pro
portions of charcoal dust and of earth, or of equal
parts of the same and of
ashes. When the hearth of the furnace is prepared, a rod that will reach to the
forehearth is put into it, higher up if the ore to be smelted readily
fuses, and
lower down if it fuses with difficulty. When the dipping-pot and forehearth
are finished, the rod is drawn out
of the furnace so that the tap-hole is open,
and through it the molten
material flows continuously into the forehearth,
which should be very
near the furnace in order that it may keep very hot and
the alloy thus
be made purer. If the ore to be smelted does not melt easily, the
hearth of the furnace
must not be made too sloping, lest the molten fluxes
should run down
into the forehearth before the ore is smelted, and the metal
thus
remain in the accretions on the sides of the furnace. The smelter must
not ram the hearth so much that it becomes too hard,
nor make the mistake
of ramming the lower part of the mouth to make it
hard, for it could not
breatheThe ore which does not readily melt is thrown as much as possible to the
back of the furnace, and toward that part where the fire burns very
fiercely, so that it may be smelted longer. In this way the smelter may direct
it whither he wills. Only when it glows at the part near the bellows' nozzle
does it signify
that all the ore is smelted which has been thrown to the side of
the
furnace in which the nozzles are placed. If the ore is easily melted, one
or two wicker baskets full are thrown
into the front part of the furnace so that
the fire, being driven back
by it, may also smelt the ore and the sows that
A, B—TWO FURNACES. C—FOREHEARTH. D—DIPPING-POTS. THE MASTER
STANDS AT
THE ONE FURNACE AND DRAWS AWAY THE SLAGS WITH AN IRON FORK.
E—IRON FORK.
F—WOODEN HOE WITH WHICH THE CAKES OF MELTED
PYRITES ARE DRAWN OUT. G—THE
FOREHEARTH CRUCIBLE: ONE-HALF INSIDE
IS TO BE SEEN OPEN IN THE OTHER FURNACE.
H—THE HThis process of smelting is very
ancient among the Tyrolese
The second method of smelting ores stands in a measure midway between
that one performed in a furnace of which the tap-hole is closed
intermittently,
and the first of the methods performed in a furnace
where the tap-hole is
always open. In this manner are smelted the ores of gold and silver that are
neither
very rich nor very poor, but mediocre, which fuse easily and are
readily absorbed by the lead. It was found that in this way a large quantity
of ore could be smelted
at one operation without much labour or great expense,
and could thus
be alloyed with lead. This furnace has two crucibles, one of
which is half inside the furnace
and half outside, so that the lead being put
into this crucible, the
part of the lead which is in the furnace absorbs
the metals of the ores
which easily fuse; the other crucible is lower, and
the alloy and the
molten pyrites run into it. Those who make use of this
method of smelting, tap the alloy of gold or
silver with lead from the upper
crucible once or twice if need be, and
throw in other lead or litharge, and
each absorbs that flux which is
nearest. This method of smelting is in use
in Styria
The furnace in the third method of smelting ores has the tap-hole
like
wise open, but the furnace is higher and wider than the
others, and its bellows
are larger; for these reasons a larger charge
of the ore can be thrown into
it. When the mines yield a great abundance of ore for the smelter, they
smelt in the same furnace continuously for three days and three nights,
providing there be no defect either in the hearth or in the forehearth. In this
kind of a furnace almost every kind of accretion will be found. The fore
hearth of the furnace is not unlike the forehearth of the
first furnace of all,
except that it has a tap-hole. However, because large charges of ore
are smelted uninterruptedly, and
the melted material runs out and the slags
are skimmed off, there is
need for a second forehearth crucible, into which the
molten material
runs through an opened tap-hole when the first is full. When
a smelter has spent twelve hours' labour on this work, another
always takes his
place. The ores of copper and lead and the poorest ores of gold and silver
are
smelted by this method, because they cannot be smelted by the other
three methods on account of the greater expense occasioned. Yet by this
method a
gold, or only a half to one
is a large amount of ore in each charge, smelting is
continuous, and without
expensive fluxes such as lead, litharge, and
hearth-lead. In this method
of smelting we must use only cupriferous pyrites which
easily melt in the
fire, in truth the cakes melted out from this, if
they no longer absorb
A, B—TWO FURNACES. C—TAP-HOLES OF FURNACES. D—FOREHEARTHS.
E—THEIR
TAP-HOLES. F—DIPPING-POTS. G—AT THE ONE
FURNACE STANDS THE SMELTER CARRYING
A WICKER BASKET FULL OF CHARCOAL.
AT THE OTHER FURNACE STANDS A SMELTER WHO
WITH THE THIRD HOOKED BAR
BREAKS AWAY THE MATERIAL WHICH HAS FROZEN THE TAP
HOLE OF THE
FURNACE. H—HOOKED BAR. I—HEAP OF CHARCOAL. K—BARROW ON
If
from this poor ore, with melted pyrites alone, material for cakes
cannot
be made, there are added other fluxes which have not previously
been
melted. These fluxes are, namely, lead ore, stones easily fused by fire
of the
second order and sand made from them, limestone,
schist, and iron
stone
Although this method of smelting ores is rough and might not seem to
be
of great use, yet it is clever and useful; for a great weight of ores, in
which the gold, silver, or copper are in small quantities, may be
reduced into
a few cakes containing all the metal. If on being first melted they are too
crude to be suitable for the
second melting, in which the lead absorbs the
precious metals that are
in the cakes, or in which the copper is melted out of
them, yet they
can be made suitable if they are repeatedly roasted, some
times as
often as seven or eight times, as I have explained in the last book.
Smelters of this kind are so clever and expert, that in smelting they take
out
all the gold and silver which the assayer in assaying the ores has
stated to be
contained in them, because if during the first operation,
when he makes the
cakes, there is a
the smelter obtains it from the slags by the second smelting. This method of
smelting ores is old and very common to most of those who
use other methods.
Although lead ores are usually smelted in the third furnace—whose
tap
hole is always open,—yet not a few people melt them in
special furnaces by a
method which I will briefly explain. The
and afterward
break and crush them with large round mallets. Between
the two low walls of a hearth, which is inside a furnace made of
and vaulted
with a rock that resists injury by the fire and does not
burn into chalk, they
place green wood with a layer of dry wood on the
top of it; then they throw
the ore on to this, and when the wood is
kindled the lead drips down and
runs on to the underlying sloping
hearthThis hearth is made of pulverised
furnace and the other half outside it, into which runs the lead. The
smelter, having first skimmed off the slags and other things with a
hoc, pours
the lead with a ladle into moulds, taking out the cakes
after they have
cooled. At the back of the furnace is a rectangular hole, so that the fire
may
be allowed more draught, and so that the smelter can crawl through it
into the furnace if necessity demands.
The Saxons who inhabit Gittelde, when smelting lead ore in a furnace
not
unlike a baking oven, put the wood in through a hole at the back of the
furnace, and when it begins to burn vigorously the lead trickles out of
the
ore into a forehearth. When this is full, the smelting being accomplished,
the tap-hole is
opened with a bar, and in this way the lead, together with the
slags,
runs into the dipping-pots below. Afterward the cakes of lead, when
they are cold, are taken from the
moulds.
In Westphalia they heap up ten wagon-loads of charcoal on some
hill
side which adjoins a level place, and the top of the heap
being made flat,
straw is thrown upon it to the thickness of three or
four digits. On the top of
kindled, and when the wind blows,
it fans the fire so that the ore is smelted. In this wise the lead, trickling down from the heap, flows on to the level
and
forms broad thin slabs. A few hundred pounds of lead ore are kept at hand,
which, if things go
well, are scattered over the heap. These broad slabs are
impure and are laid upon dry wood which in turn is
placed on green wood
laid over a large crucible, and the former having
been kindled, the lead is
re-melted.
The Poles use a hearth of bricks four feet high, sloping on both sides and
plastered with lute. On the upper level part of the hearth large pieces of
wood are piled,
and on these is placed small wood with lute put in between;
over the
top are laid wood shavings, and upon these again pure lead ore
covered
with large pieces of wood. When these are kindled, the ore melts and
A—FURNACE OF THE CARNI. B—LOW WALL. C—WOOD. D—ORE
DRIPPING LEAD.
E—LARGE CRUCIBLE. F—MOULDS. G—LADLE.
H—SLABS OF LEAD. I—RECTANGULAR
HOLE AT THE BACK OF THE
FURNACE. K—SAXON FURNACE. L—OPENING IN THE BACK
OF THE
FURNACE. M—WOOD. N—UPPER CRUCIBLE. O—DIPPING-POT.
P—WESTPHALIAN
METHOD OF MELTING. Q—HEAPS OF CHARCOAL.
R—STRAW. S—WIDE SLABS.
the fire,
the metal is collected. If necessity demand, it is melted over and
over again in the same
manner, but it is finally melted by means of wood
laid over the large
crucible, the slabs of lead being placed upon it.
The concentrates from washing are smelted together with slags (fluxes?)
in a third furnace, of which the tap-hole is always open.
It is worth while to build vaulted dust-chambers over the furnaces,
especially over those in which the precious ores are to be smelted, in
order
that the thicker part of the fumes, in which metals are not
wanting, may be
caught and saved. In this way two or more furnaces are combined under the
same vaulted
ceiling, which is supported by the wall, against which the
furnaces are
built, and by four columns. Under this the smelters of the
ore perform their work. There are two openings through which the fumes
rise from the furnaces
into the wide vaulted chamber, and the wider this is the
more fumes it
collects; in the middle of this chamber over the arch is an opening
three palms high and two wide. This catches the fumes of both furnaces,
which have risen up from both
sides of the vaulted chamber to its arch, and
have fallen again because
they could not force their way out; and they thus
pass out through the
opening mentioned, into the chimney which the Greeks
call The chimney has
thin iron plates fastened into the walls, to which the
thinner metallic sub
stances adhere when ascending with the fumes. The thicker metallic
substances, or
harden into
stalactites. On one side of the chamber is a window in which
are set panes of glass,
so that the light may be transmitted, but the fumes
kept in; on the
other side is a door, which is kept entirely closed while the
ores are
being smelted in the furnaces, so that none of the fumes may escape.
It is opened in order that the workman, passing through it, may be enabled
to enter the chamber and remove the soot and
A—FURNACES. B—VAULTED ROOF. C—COLUMNS.
D—DUST-CHAMBER. E—OPENING.
F—CHIMNEY. G—WINDOW.
H—DOOR. I—CHUTE.The soot mixed with
a long
chute made of four boards joined in the shape of a rectangle,
that they
should not fly away. They fall on to the floor, and are sprinkled
with salt water, and are
again smelted with ore and litharge, and become
an emolument to the
proprietors. Such chambers, which catch the metallic
substances that rise with the
fumes, are profitable for all metalliferous
ores; but especially for
the minute metallic particles collected by washing
crushed ores and
rock, because these usually fly out with the fire of the
furnaces.
I have explained the four general methods of smelting ores; now I
will
state how the ores of each metal are smelted, or how the metal is obtained
from the ore. I will begin with gold.
Its sand, the concentrates from
washing, or the gold dust collected in
any other manner, should very often
not be smelted, but should be mixed
with quicksilver and washed with tepid
water, so that all the
impurities may be eliminated. This method I ex
plained in Book VII. Or they are placed in the
gold from silver, for this also separates its
impurities. In this method we
see the gold sink in the glass ampulla, and after all
the
from the particles, it frequently remains as a gold-coloured residue at
the
bottom; this powder, when it has been moistened with oil made from
argol
or with saltpetre
and salt; or the same very fine dust is thrown into molten
silver,
which absorbs it, and from this it is again parted by
It is necessary to smelt gold ore either outside the blast furnace in a
crucible, or inside the blast furnace; in the former case a small
charge of ore
is used, in the latter a large charge of it.
it is, is crushed with a
slow fire for three hours, then the alloy is put
into molten silver that it
may melt more rapidly. Or a
mixed together with half a
into a crucible with half an
melt, then a sixth part of granulated lead is thrown into
the same crucible. As soon as the mixture emits an odour, iron-filings are added to it, or if
these
are not at hand, iron hammer-scales, for both of these break the
strength of
the When the fire consumes it, not alone with it is some strength
of the
be mixed
with the goldWhen the button has been taken out of the
crucible and cooled, it is
melted in a cupel, first until the antimony is exhaled,
and thereafter
until the lead is separated from it.
Crushed pyrites which contains gold is smelted in the same way; it
and
the
made from them
in a number of different waysOne part of crushed
material is mixed with six parts of copper, one part
of sulphur, half a part of
salt, and they are all placed in a pot and
over them is poured wine distilled
by heating liquid argol in an
ampulla. The pot is covered and smeared
over with lute and is put in a hot place,
so that the mixture moistened with
wine may dry for the space of six
days, then it is heated for three hours over
a gentle fire that it may
combine more rapidly with the lead. Finally it is put
into a cupel and the gold is separated from the
lead
Or else one
to which gold
adheres, is mixed with half a
a third of a
The crucible into which these are put, after it has been
covered with a
lid, is sealed with lute and placed in a small furnace that is
provided
with small holes through which the air is drawn in, and then it is
heated until it turns red and the substances put in have alloyed; this
should
take place within four or five hours. The alloy having cooled, it is again
crushed to powder and a pound of
litharge is added to it; then it is heated
again in another crucible
until it melts. The button is taken out, purged of
slag, and placed in a cupel, where
the gold is separated from the lead.
Or to a
concentrates, is added a
glass-galls, and it is heated until it
melts. When cooled and crushed, it is washed,
then to it is added a
and it is likewise heated again
until it melts. After the button has been
purged of slag, it is put into the cupel, and
the gold and silver are separated
from the lead; the gold is parted
from the silver with Or else
a
a quarter
of a
which fuses
ores, are heated until they melt. The mixture when cooled is again
reduced to powder, roasted and washed,
and in this manner a blue powder is
obtained. Of this, and silver, and that second powder which fuses ores, a
button is treated as before. Or else a
such metalliferous concentrates, half a The alloy when cooled is again
crushed to powder, one
silver. Or else a
together with a
salt made from argol, and a third of a
with sulphur, are heated until they melt. Afterward the lead is re-melted,
and the gold is separated from the
other metals. Or else a
powder of this kind of concentrates, together with two
gold is melted out. By these and similar methods concentrates containing
gold, if there be a
small quantity of them or if they are very rich, can be
smelted outside
the blast furnace.
If there be much of them and they are poor, then they are smelted in the
blast furnace, especially the ore which is not crushed to powder, and
particularly
when the gold mines yield an abundance of itThe gold concentrates mixed
with litharge and hearth-lead, to which are
added iron-scales, are smelted in the
blast furnace whose tap-hole is
intermittently closed, or else in the first or the
second furnaces in
which the tap-hole is always open. In this manner an
Two parts of roasted pyrites or
one part of
unroasted, and are smelted together in the third furnace whose
tap-hole
is always open, and are made into cakes. When these cakes have
been repeatedly roasted, they are re-smelted in
the furnace whose tap
hole is temporarily closed, or in one of the
two others whose tap-holes are
always open. In this manner the lead absorbs the gold, whether pure or
argentiferous
or cupriferous, and the alloy is taken to the cupellation
furnace. Pyrites, or other gold ore which is mixed with much material that
is
consumed by fire and flies out of the furnace, is melted with stone from
which iron is melted, if this is at hand. Six parts of such pyrites, or of gold
ore reduced to powder and sifted,
four of stone from which iron is made, like
wise crushed, and three
of slaked lime, are mixed together and moistened
with water; to these
are added two and a half parts of the cakes which
contain some copper,
together with one and a half parts of slag. A basket
ful of fragments of the cakes is thrown into the furnace,
then the mixture
of other things, and then the slag. Now when the middle part of the
forehearth is filled with the molten
material which runs down from the
furnace, the slags are first skimmed
off, and then the cakes made of pyrites;
afterward the alloy of copper,
gold and silver, which settles at the bottom,
is taken out. The cakes are gently roasted and re-smelted with lead, and
made into
cakes, which are carried to other works. The alloy of copper,
gold, and silver is not roasted, but is re-melted
again in a crucible with an
equal portion of lead. Cakes are also made much richer in copper and gold
than those I spoke
of. In order that the alloy of gold and silver may be
ore, three
of a
heated together in the crucible until they
melt. When the slag and the
cakes melted from pyrites have been skimmed off,
the alloy is carried to
other furnaces.
There now follows silver, of which the native silver or the lumps of
silver
small iron pans, of which I will
speak at the proper place; these lumps
are heated and thrown into
molten silver-lead alloy in the cupellation furnace
when the silver is
being separated from the lead, and refined. The tiny flakes
or tiny lumps of silver adhering to stones or marble or
rocks, or again the
same little lumps mixed with earth, or silver not
pure enough, should be
smelted in the furnace of which the tap-hole is
only closed for a short time,
together with cakes melted from pyrites,
with silver slags, and with stones
which easily fuse in fire of the
second order.
In order that particles of silver should not fly away
of ore consisting of
minute threads of pure silver and twigs of native silver,
they are
enclosed in a pot, and are placed in the same furnace where the rest of
the silver ores are being smelted. Some people smelt lumps of native silver
not sufficiently pure, in pots
or triangular crucibles, whose lids are sealed with
lute. They do not place these pots in the blast furnace, but arrange them in
the assay furnace into which the draught of the air blows through small
holes. To one part of the native silver they add three parts of powdered litharge,
as
many parts of hearth-lead, half a part of galena
salt and
iron-scales. The alloy which settles at the bottom of the other
substances in the pot
is carried to the cupellation furnace, and the slags are
re-melted with
the other silver slags. They crush under the stamps and
wash the pots or crucibles to which
silver-lead alloy or slags adhere, and
having collected the
concentrates they smelt them together with the slags. This method of smelting
best, because the
smallest portion of silver does not fly out of the pot or the
crucible,
and get lost.
If bismuth ore or antimony ore or lead ore
smelted with the other ores of
silver; likewise galena or pyrites, if there is
a small amount of it. If there be much galena, whether it contain a large
or a small amount of
silver, it is smelted separately from the others;
which process I will
explain a little further on.
Because lead and copper ores and their metals have much in common
with
silver ores, it is fitting that I should say a great deal concerning them,
both now and later on. Also in the same manner, pyrites are smelted separ
ately if there be
much of them. To three parts of roasted lead or copper
ore and one part of crude ore,
are added concentrates if they were made by
washing the same ore,
together with slags, and all are put in the third furnace
whose
tap-hole is always open. Cakes are made from this charge, which,
when they have been quenched
with water, are roasted. Of these roasted
cakes generally four parts are again mixed with one
part of crude pyrites
and re-melted in the same furnace. Cakes are again made from this charge,
and if there is a large amount of
copper in these cakes, copper is made
immediately after they have been
roasted and re-melted; if there is little
copper in the cakes they are
also roasted, but they are re-smelted with a little
soft slag. In this method the molten lead in the forehearth absorbs the
silver. From the pyritic material which floats on the top of the forehearth
are
made cakes for the third time, and from them when they have been
roasted and re-smelted is made copper. Similarly, three parts of roasted
together
with slag, and this charge is smelted and cakes are made from it;
these
cakes having been roasted are re-smelted in the same furnace. By this
method the lead contained in the forehearth absorbs the silver,
and the silver
lead is taken to the cupellation furnace. Crude quartz and stones which
easily fuse in fire of the third order,
together with other ores in which there
is a small amount of silver,
ought to be mixed with crude roasted pyrites or
profitably smelted separately. In a similar manner earths which contain
little silver are mixed with
the same; but if pyrites and
available to the smelter, he smelts such
silver ores and earths with litharge,
hearth-lead, slags, and stones
which easily melt in the fire. The concentrates
originating
from the washing of
they melt, are smelted with mixed litharge and hearth-lead, or
else, after
being moistened with water, they are smelted with cakes
made from pyrites
and By neither of these methods do (the concentrates) fall
back in the
furnace, or fly out of it, driven by the blast of the bellows and the
agitation of the fire. If the concentrates originated from galena they are
smelted with it
after having been roasted; and if from pyrites, then with
pyrites.
Pure copper ore, whether it is its own colour or is tinged with chrysocolla
or azure, and copper glance, or grey or black
furnace
of which the tap-hole is closed for a very short time, or else is always
If there is a large amount of silver in the ore it is run into the
fore
hearth, and the greater part of the silver is absorbed by the
molten lead, and
the remainder is sold with the copper to the
proprietor of the works in which
silver is parted from copperIf there is a small amount of silver in the ore,
no lead is put into the
forehearth to absorb the silver, and the above
is made direct. If such copper ore contains some minerals which do not
easily melt, as
pyrites or
is melted, then crude
pyrites which easily fuse are added to it, together
with slag. From this charge, when smelted, they make cakes; and from
the copper is made. But if there be some silver in the cakes, for which an
outlay of lead
has to be made, then it is first run into the forehearth, and
the
molten lead absorbs the silver.
Indeed,
purple, blackish and
occasionally in parts blue, is smelted in the first
furnace whose
tap-hole is always open. This is the method of the Tyrolese.
To as much
three—adds three cartloads of lead
slags, one cartload of schist, one fifth of
a
quantity of concentrates collected from
copper slag and accretions, all of
which he smelts for the space of
twelve hours, and from which he makes six One half of the latter consists of copper and silver, and it settles to the
bottom
of the forehearth. In every
of silver and sometimes half an In this way every week,
if the work is for six days, thirty-six
three The second smelter separates from the primary cakes the
greater part of
the silver by absorbing it in lead. To eighteen
of cakes made from crude copper ore, he adds twelve
lead and litharge, three
five
exhausted liquation cakes
from smelting crude copper,
together with a small quantity of concentrates
made from accretions,
all of which he melts for the space of twelve hours,
and makes eighteen
pondia
there is half a After he has taken off the cakes with a
hooked bar, he pours the alloy
out into copper or iron moulds; by this
method they make four cakes of
alloy, which are carried to the works in
which silver is parted from
copper. On the following day, the same smelter,
taking eighteen
from which lead
is smelted, five
together with slags
from the smelting of the primary cakes, and with concen
trates
washed from the accretions which are usually made at that time. This charge is likewise smelted for the space of twelve hours, and he makes
as
many as thirteen
of copper-lead-silver
alloy, each
third of a When he has skimmed off the
tertiary cakes with a hooked bar, the alloy
is poured into copper moulds, and
by this method four cakes of alloy
are made, which, like the preceding four
cakes of alloy, are carried to
the works in which silver is parted from copper. By this method the second smelter makes primary cakes on alternate days
and secondary cakes on the intermediate days. The third smelter takes
eleven cartloads of the tertiary cakes and adds
to them three cartloads of
hard cakes poor in silver, together with the
slag from smelting the secondary
cakes, and the concentrates from the
accretions which are usually made
at that time. From this charge when smelted, he makes twenty
pondía
fifteen
pondiumThese latter cakes the
second smelter, as I said before, adds to the
primary and secondary cakes
when he re-melts them. In the same way, from eleven cartloads of qua
ternary cakes thrice
roasted, he makes the “final” cakes, of which one In this operation he
also makes fifteen These hard cakes the
them, while from the
“final” cakes, thrice roasted and re-smelted, is made
black
copper
The
silver or if it does not
easily melt, is first smelted in the third furnace of which
the
tap-hole is always open; and from this are made cakes, which after
being seven times roasted are re-smelted, and from these copper is
melted
out; the cakes of copper are carried to a furnace of another
kind, in which
they are melted for the third time, in order that in the
copper “bottoms”
there may be more silver, while in the
“tops” there may be less, which
process is explained in
Book XI.
Pyrites, when they contain not only copper, but also silver, are smelted
in the manner I described when I treated of ores of silver. But if they are
poor in silver, and if the copper which is melted out of
them cannot easily be
treated, they are smelted according to the method
which I last explained.
Finally, the copper schists containing bitumen or sulphur are roasted,
and then smelted with stones which easily fuse in a fire of the second
order,
and are made into cakes, on the top of which the slags float. From
these cakes, usually roasted seven times and re-melted, are melted
out
slags and two kinds of cakes; one kind is of copper and occupies
the
bottom of the crucible, and these are sold to the proprietors of
the works in
which silver is parted from copper; the other kind of
cakes are usually
re-melted with primary cakes. If the schist contains but a small amount of
copper, it is burned,
crushed under the stamps, washed and sieved, and
the concentrates
obtained from it are melted down; from this are made
cakes from which,
when roasted, copper is made. If either chrysocolla or azure,
or yellow or black earth containing
copper and silver, adheres to the schist,
it is not washed, but is
crushed and smelted with stones which easily
fuse in fire of the second
order.
Lead ore, whether it be
which it is melted, is often smelted in a
special furnace, of which I have
spoken above, but no less often in the
third furnace of which the tap-hole
is always open. The hearth and forehearth are made from powder containing
a small
portion of iron hammer-scales; iron slag forms the principal flux
for
such ores; both of these the expert smelters consider useful and to
the
owner's advantage, because it is the nature of iron to attract lead. If
it is
down from the
furnace into the forehearth, and when the slags have been
skimmed off,
the lead is poured out with a ladle. If pyrites are smelted,
the first to flow from the furnace into the
forehearth, as may be seen at
Goslar, is a white molten substance,
injurious and noxious to silver, for it
consumes it. For this reason the slags which float on the top having been
skimmed
off, this substance is poured out; or if it hardens, then it is taken
out with a hooked bar; and the walls of the furnace exude the same
substance
of lead and silver. From the silver-lead alloy they first skim off the slags,
not rarely
white, as some pyrites
cakes of pyrites, if there are any. In these cakes there is usually some copper;
but since there is usually
but a very small quantity, and as the forest From the silver
lead poured into iron moulds they likewise make
cakes: when these cakes
have been melted in the cupellation furnace,
the silver is parted from the
lead, because part of the lead is
transformed into litharge and part into
hearth-lead, from which in the
blast furnace on re-melting they make
dium
The little black stones
in their own kind of furnace, which
should be narrower than the other
furnaces, that there may be only the
small fire which is necessary for this
ore. These furnaces are higher, that the height may compensate for the
narrowness and make them of almost the same capacity as the other
furnaces. At the top, in front, they are closed and on the other side they are open,
where
there are steps, because they cannot have the steps in front on
account of the
forehearth; the smelters ascend by these steps to put
the tin-stone into the
furnace. The hearth of the furnace is not made of powdered earth and
char
coal, but on the floor of the works are placed sandstones
which are not too
hard; these are set on a slight slope, and are two
and three-quarters feet
long, the same number of feet wide, and two
feet thick, for the thicker they are
the longer they last in the fire. Around them is constructed a rectangular
furnace eight or nine feet
high, of broad sandstones, or of those common
substances which by
nature are composed of diverse materialsOn the
inside the furnace is everywhere evenly covered with lute. The upper part
of the interior is two feet long and one foot wide, but
below it is not so long
and wide. Above it are two hood-walls, between which the fumes ascend
from the
furnace into the dust chamber, and through this they escape by a
narrow
opening in the roof. The sandstones are sloped at the bed of the
furnace, so that the tin
melted from the tin-stone may flow through the tap
hole of the
furnace into the forehearth.
As there is no need for the smelters to have a fierce fire, it is not
necessary
to place the nozzles of the bellows in bronze or iron pipes,
but only through a
hole in the furnace wall. They place the bellows higher at the back so that
the blast from the
nozzles may blow straight toward the tap-hole of the
furnace. That it may not be too fierce, the nozzles are wide, for if the fire
were fiercer, tin could not be melted out from the tin-stone, as it
would be
consumed and turned into ashes. Near the steps is a hollowed stone,
in which is placed the tin-stone to
be smelted; as often as the smelter
throws into the furnace an iron
shovel-ful of this tin-stone, he puts on char
coal that was first
put into a vat and washed with water to be cleansed from the
grit and
small stones which adhere to it, lest they melt at the same time as the
tin-stone and obstruct the tap-hole and impede the flow of tin from the
furnace. The tap-hole of the furnace is always open; in front of it is a
fore
hearth a little more than half a foot deep, three-quarters of
two feet long and
one foot wide; this is lined with lute, and the tin
from the tap-hole flows into it. On one side of the forehearth is a low wall, three-quarters of a foot wider
and one foot longer than the forehearth, on which lies charcoal powder.
On the other side the floor of the building slopes, so that the slags may
con
veniently run down and be carried away. As soon as the tin begins to run
from the tap-hole of the furnace into
the forehearth, the smelter scrapes
may be
separated from the hot metal, and so that it may be covered, lest
any
part of it, being very hot, should fly away with the fumes. If after
the slag has been skimmed off, the powder does not cover up the
whole of the
tin, the smelter draws a little more charcoal off the wall
with a scraper. After
he has opened the tap-hole of the forehearth with a tapping-bar,
in order
that the tin can flow into the tapping-pot, likewise smeared
with lute, he
again closes the tap-hole with pure lute or lute mixed
with powdered charcoal. The smelter, if he be diligent and experienced, has brooms at hand with which
he sweeps down the walls above the furnace; to these walls and to the
dust chamber minute tin-stones sometimes adhere with part of the fumes.
If he be not sufficiently experienced in these matters and has melted at the
same time all of the tin-stone,—which is commonly of three sizes,
large,
medium, and very small,—not a little waste of the
proprietor's tin results;
because, before the large or the medium sizes
have melted, the small have either
been burnt up in the furnace, or
else, flying up from it, they not only adhere to
the walls but also
fall in the dust chamber. The owner of the works has
the sweepings by right from the owner of the
ore. For the above reasons
the most experienced smelter melts them down
separately; indeed, he
melts the very small size in a wider furnace,
the medium in a medium-sized
furnace, and the largest size in the
narrowest furnace. When he melts down
the small size he uses a gentle blast from the
bellows, with the medium-sized
a moderate one, with the large size a
violent blast; and when he smelts
the first size he needs a slow fire,
for the second a medium one, and for the
third a fierce one; yet he
uses a much less fierce fire than when he smelts
the ores of gold,
silver, or copper. When the workmen have spent three
consecutive days and nights in this
work, as is usual, they have finished
their labours; in this time they
are able to melt out a large weight of small
slowly, and a moderate quantity of the medium-sized which holds the
middle
course. Those who do not smelt the tin-stone in furnaces made sometimes
wide,
sometimes medium, or sometimes narrow, in order that great loss
should
not be occasioned, throw in first the smallest size, then the medium,
then the large size, and finally those which are not quite pure; and
the blast
of the bellows is altered as required. In order that the tin-stone thrown
into the furnace should not roll off
from the large charcoal into the forehearth
before the tin is melted
out of it, the smelter uses small charcoal; first some
of this
moistened with water is placed in the furnace, and then he frequently
repeats this succession of charcoal and tin-stone.
The tin-stone, collected from material which during the summer was
washed in a ditch through which a stream was diverted, and during the
winter
was screened on a perforated iron plate, is smelted in a furnace
a palm wider
than that in which the fine tin-stone dug out of the earth
is smelted. For
the smelting of these, a more vigorous blast of the bellows and a
fiercer fire
is needed than for the smelting of the large tin-stone. Whichever kind of
tin-stone is being smelted, if the tin first flows
from the furnace, much of it is
made, and if slags first flow from the
furnace, then only a little. It happens
that the tin-stone is mixed with the slags when it is either
less pure or
ferruginous—that is, not enough roasted—and is
imperfect when put into
the furnace, or when it has been put in in a
larger quantity than was neces
sary; then, although it may be pure
and melt easily, the ore either runs
out of the furnace at the same
time, mixed with the slags, or else it settles
so firmly at the bottom
of the furnace that the operation of smelting being
necessarily
interrupted, the furnace freezes up.
The tap-hole of the forehearth is opened and the tin is diverted into the
dipping-pot, and as often as the slags flow down the sloping floor of
the build
ing they are skimmed off with a rabble; as soon as the
tin has run out of
the forehearth, the tap-hole is again closed up with
lute mixed with powdered
charcoal. Glowing coals are put in the dipping-pot so that the tin, after it
has
run out, should not get chilled. If the metal is so impure that nothing
can be made from it, the material
which has run out is made into cakes to be
re-smelted in the hearth, of
which I shall have something to say later; if the
metal is pure, it is
poured immediately upon thick copper plates, at first in
straight lines
and then transversely over these to make a lattice. Each of
these lattice bars is impressed with an iron die; if the tin was
melted out
of ore excavated from mines, then one stamp only, namely,
that of the
Magistrate, is usually imprinted, but if it is made from
tin-stone collected on
the ground after washing, then it is impressed
with two seals, one the
Magistrate's and the other a fork which the
washers use. Generally, three
of this kind of lattice bars are beaten and amalgamated
into one mass with a
wooden mallet.
The slags that are skimmed off are afterward thrown with an iron shovel
into a small trough hollowed from a tree, and are cleansed from
charcoal
A—FURNACE. B—ITS TAP-HOLE. C—FOREHEARTH. D—ITS
TAP-HOLE. E—SLAGS.
F—SCRAPER. G—DIPPING-POT.
H—WALLS OF THE CHIMNEY. I—BROOM.
K—COPPER PLATE.
L—LATTICEWORK BARS. M—IRON SEAL OR DIE. N—HAMMER.
and then they are re-melted with the fine tin-stone
next smelted. There
are some who crush the slags three times under wet stamps and
re-melt them
three times; if a large quantity of this be smelted while
still wet, little
tin is melted from it, because the slag, soon melted
again, flows from the
furnace into the forehearth. Under the wet stamps are also crushed the
lute and broken rock with
which such furnaces are lined, and also the
accretions, which often
contain fine tin-stone, either not melted or half
melted, and also
prills of tin. The tin-stone not yet melted runs out
through the screen into a trough,
and is washed in the same way as tin
stone, while the partly melted
and the prills of tin are taken from the mortar
box and washed in
the sieve on which not very minute particles remain, and
thence to the
canvas strake. The soot which adheres to that part of the
chimney which emits the
smoke, also often contains very fine tin-stone which
flies from the
furnace with the fumes, and this is washed in the strake which
I have
just mentioned, and in other sluices. The prills of tin and the partly
melted tin-stone that are contained in
the lute and broken rock with which
the furnace is lined, and in the
remnants of the tin from the forehearth and
the dipping-pot, are
smelted together with the tin-stone.
When tin-stone has been smelted for three days and as many nights in a
furnace prepared as I have said above, some little particles of the
rock from
which the furnace is constructed become loosened by the fire
and fall down;
and then the bellows being taken away, the furnace is
broken through at the
back, and the accretions are first chipped off
with hammers, and afterward
the whole of the interior of the furnace is
re-fitted with the prepared sand
stone, and again evenly lined with
lute. The sandstone placed on the bed
of the furnace, if it has become faulty,
is taken out, and another is laid down
in its place; those rocks which
are too large the smelter chips off and fits
with a sharp pick.
Some build two furnaces against the wall just like those I have described,
and above them build a vaulted ceiling supported by the wall and by
four
pillars. Through holes in the vaulted ceiling the fumes from the furnaces
ascend
into a dust chamber, similar to the one described before, except that
there is a window on each side and there is no door. The smelters, when
they have to clear away the flue-dust, mount by the
steps at the side of the
furnaces, and climb by ladders into the dust
chamber through the apertures
in the vaulted ceilings over the
furnaces. They then remove the flue-dust
from everywhere and collect it in
baskets, which are passed from one to the
other and emptied. This dust chamber differs from the other described, in
the fact that the
chimneys, of which it has two, are not dissimilar to those
of a house;
they receive the fumes which, being unable to escape through the
upper
part of the chamber, are turned back and re-ascend and release the
tin;
thus the tin set free by the fire and turned to ash, and the little
tin
stones which fly up with the fumes, remain in the dust chamber
or else adhere
to copper plates in the chimney.
A—FURNACES. B—FOREHEARTHS. C—THEIR TAP-HOLES.
D—DIPPING-POTS. E—PILLARS.
F—DUST-CHAMBER.
G—WINDOW. H—CHIMNEYS. I—TUB IN WHICH THE COALS ARE
WASHED.
If the tin is so impure that it cracks when struck with the hammer, it
is not immediately made into lattice-like bars, but into the cakes
which I have
spoken of before, and these are refined by melting again
on a hearth. This
hearth consists of sandstones, which slope toward the centre and a
little
toward a dipping-pot; at their joints they are covered with
lute. Dry
logs are arranged on each side, alternately upright and lengthwise,
and more
closely in the middle; on this wood are placed five or six
cakes of tin which
all together weigh about six
A—HEARTHS. B—DIPPING-POTS. C—WOOD. D—CAKES.
E—LADLE. F—COPPER
PLATE. G—LATTICE-SHAPED BARS.
H—IRON DIES. I—WOODEN MALLET. K—MASS
OF TIN BARS.
L—SHOVEL.
the tin drips down and flows continuously into the
dipping-pot which
is on the floor. The impure tin sinks to the bottom of this dipping-pot
and the pure tin
floats on the top; then both are ladled out by the master,
who first
takes out the pure tin, and by pouring it over thick plates of copper
makes lattice-like bars. Afterward he takes out the impure tin from which
he makes cakes; he
discriminates between them, when he ladles and pours,
by the ease or
difficulty of the flow. One
bare sells for more than a These lattice-like bars are
lighter than the others, and when five of
them are pounded and amalgamated
with a wooden mallet, a mass is made
which is stamped with an iron die. There are some who do not make a dipping-pot on the floor for the tin to run
into, but in the hearth itself; out of this the master, having removed
the
charcoal, ladles the tin and pours it over the copper-plate. The dross which
adheres to the wood and the charcoal, having been
collected, is re-smelted
in the furnace.
A—FURNACE. B—BELLOWS. C—IRON DISC. D—NOZZLE.
E—WOODEN DISC.
F—BLOW-HOLE. G—HANDLE. H—HAFT.
I—HOOPS. K—MASSES OF TIN.
Some of the Lusitanians melt tin from tin-stone in small furnaces.
They
use round bellows made of leather, of which the fore end is a round
iron disc
and the rear end a disc of wood; in a hole in the former is
fixed the nozzle,
in the middle of the latter the blow-hole. Above this is the handle or haft,
which draws open the round bellows and
lets in the air, or compresses it and
drives the air out. Between the discs are several iron hoops to which the
leather is
fastened, making such folds as are to be seen in paper lanterns that Since this kind of bellows does not give a vigorous blast,
because they
are drawn apart and compressed slowly, the smelter is not
able during a
whole day to smelt much more than half a
tin.
Very good iron ore is smelted
furnace. The hearth is three and a half feet high, and five feet long and
wide;
in the centre of it is a crucible a foot deep and one and a half feet
wide, but it may be deeper or shallower, wider or narrower, according
to whether
more or less ore is to be made into iron. A certain quantity of iron ore is
given to the master, out of which he
may smelt either much or little iron. He being about to expend his skill and labour on this matter, first throws
charcoal into the crucible, and sprinkles over it an iron shovel-ful of
crushed
iron ore mixed with unslaked lime. Then he repeatedly throws on charcoal
and sprinkles it with ore, and
continues this until he has slowly built up a
heap; it melts when the
charcoal has been kindled and the fire violently
stimulated by the
blast of the bellows, which are skilfully fixed in a pipe.
and again sometimes in twelve. In order that the heat of the fire should not
burn his face, he covers
it entirely with a cap, in which, however, there are
holes through
which he may see and breathe. At the side of the hearth is a
bar which he raises as often as is
necessary, when the bellows blow too violent
a blast, or when he adds
more ore and charcoal. He also uses the bar
to draw off the slags, or to open or close the
gates of the sluice, through
which the waters flow down on to the wheel
which turns the axle that com
presses the bellows. In this sensible way, iron is melted out and a mass
weighing two or
three
was rich. When this is done the master opens the slag-vent with the
tapping
bar, and when all has run out he allows the iron mass to
cool. Afterward
he and his assistant stir the iron with the bar, and then in
order to chip off
the slags which had until then adhered to it, and to
condense and flatten it,
they take it down from the furnace to the
floor, and boat it with large wooden
mallets having slender handles
five feet long. Thereupon it is immediately
A—HEARTH. B—HEAP. C—SLAG-VENT. D—IRON MASS.
E—WOODEN MALLETS.
F—HAMMER. G—ANVIL.
raised by the cams of an axle turned by a water-wheel. Not long afterward
it is taken up with tongs and placed under the same
hammer, and cut up with
a sharp iron into four, five, or six pieces,
according to whether it is large or
small. These pieces, after they have been re-heated in the blacksmith's forge
and again placed on the anvil, are shaped by the smith into square bars
or into
ploughshares or tyres, but mainly into bars. Four, six, or eight of these bars
weigh one-fifth of a
ments. During the blows from the hammer by which it is shaped by the smith,
a
youth pours water with a ladle on to the glowing iron, and this is why the
blows make such a loud sound that they may be heard a long distance
from
the works. The masses, if they remain and settle in the crucible of the
furnace in
which the iron is smelted, become hard iron which can only be
hammered
with difficulty, and from these they make the iron-shod heads for
the
stamps, and such-like very hard articles.
But to iron ore which is cupriferous, or which when heated
with difficulty, it is necessary
for us to give a fiercer fire and more labour;
because not only must we
separate the parts of it in which there is metal from
those in which
there is no metal, and break it up by dry stamps, but we must
also
roast it, so that the other metals and noxious juices may be exhaled;
and we must wash it, so that the lighter parts may be separated from
it. Such ores are smelted in a furnace similar to the blast furnace, but much
wider and higher, so that it may hold a great quantity of ore and much
charcoal; mounting the stairs at the side of the furnace, the smelters
fill
it partly with fragments of ore not larger than nuts, and partly
with
charcoal; and from this kind of ore once or twice smelted they
make iron
which is suitable for re-heating in the blacksmith's forge,
after it is flattened
out with the large iron hammer and cut into
pieces with the sharp iron.
By skill with fire and fluxes is made that kind of iron from which steel
is made, which the Greeks call
is easy to melt,
is hard and malleable. Now although iron may be
smelted from ore which contains other metals,
yet it is then either soft
or brittle; such (iron) must be broken up
into small pieces when it is
A—FURNACE. B—STAIRS. C—ORE. D—CHARCOAL.
A—FORGE. B—BELLOWS. C—TONGS. D—HAMMER. E—COLD
STREAM.
Then a crucible
is made in the hearth of the smith's furnace, from the
same moistened
powder from which are made the forehearths in front of
the furnaces in
which ores of gold or silver are smelted; the width of
this crucible is
about one and a half feet and the depth one foot. The bellows are so
placed that the blast may be blown through the nozzle
into the middle
of the crucible. Then the whole of the crucible is filled with the best
charcoal, and it
is surrounded by fragments of rock to hold in place the pieces
of iron
and the superimposed charcoal. As soon as all the charcoal
is kindled and the crucible is glowing, a
blast is blown from the bellows
and the master pours in gradually as
much of the mixture of iron and flux
as he wishes. Into the middle of this, when it is melted, he puts four iron
masses
each weighing thirty pounds, and heats them for five or six hours in a
fierce fire; he frequently stirs the melted iron with a bar, so that
the small
pores in each mass absorb the minute particles, and these
particles by their
own strength consume and expand the thick particles
of the masses, which they
render soft and similar to dough. Afterward the master, aided by his
assistant, takes out a mass with the
tongs and places it on the anvil, where
it is pounded by the hammer
which is alternately raised and dropped by
means of the water-wheel;
then, without delay, while it is still hot, he
throws it into water and
tempers it; when it is tempered, he places it again
on the anvil, and
breaks it with a blow from the same hammer. Then at
once examining the fragments, he decides whether the iron in
some part or
other, or as a whole, appears to be dense and changed into
steel; if so, he seizes
one mass after another with the tongs, and
taking them out he breaks them
into pieces. Afterward he heats the mixture up again, and adds a portion
afresh to
take the place of that which has been absorbed by the masses. This
restores the energy of that which is left, and the pieces of the
masses are again
put back into the crucible and made purer. Each of these, after having
been heated, is seized with the tongs, put
under the hammer and shaped
into a bar. While they are still glowing, he at once throws them into the very
coldest nearby running water, and in this manner, being suddenly
condensed,
they are changed into pure steel, which is much harder and
whiter than iron.
The ores of the other metals are not smelted in furnaces.
Quicksilver
ores and also antimony are melted in pots, and bismuth in
troughs.
I will first speak of quicksilver.
This is collected when found in pools
formed from the outpourings of the
veins and stringers; it is cleansed with
vinegar and salt, and then it
is poured into canvas or soft leather, through
which, when squeezed and
compressed, the quicksilver runs out into a pot or
pan. The ore of quicksilver is reduced in double or single pots.
If in double
pots, then the upper one is of a shape not very dissimilar
to the glass ampullas
used by doctors, but they taper downward toward
the bottom, and the
lower ones are little pots similar to those in
which men and women make
cheese, but both are larger than these; it is
necessary to sink the lower
pots up to the rims in earth, sand, or
ashes. The ore, broken up into small
pieces is put into the upper pots; these
having been entirely closed up
are joined
with lute, lest the quicksilver which takes refuge in them should
be
exhaled. There are some who, after the pots have been buried, do not fear
to
leave them uncemented, and who boast that they are able to produce no
less weight of quicksilver than those who do cement them, but
nevertheless
cementing with lute is the greatest protection against
exhalation. In this
manner seven hundred pairs of pots are set together in the
ground or on a
hearth. They must be surrounded on all sides with a mixture consisting of
crushed earth and charcoal, in such a way that the upper pots protrude
to a
height of a palm above it. On both sides of the hearth rocks are first laid,
and upon them poles,
across which the workmen place other poles transversely;
these poles do
not touch the pots, nevertheless the fire heats the quick
silver,
which fleeing from the heat is forced to run down through the moss
into
the lower pots. If the ore is being reduced in the upper pots, it flees
from them,
wherever there is an exit, into the lower pots, but if the ore on
the
contrary is put in the lower pots the quicksilver rises into the upper pot
or into the operculum, which, together with the gourd-shaped vessels,
are
cemented to the upper pots.
A—HEARTH. B—POLES. C—HEARTH WITHOUT FIRE IN WHICH THE POTS
ARE PLACED.
D—ROCKS. E—ROWS OF POTS. F—UPPER POTS.
G—LOWER POTS.
The pots, lest they should become defective, are moulded from the best
potters' clay, for if there are defects the quicksilver flies out in
the fumes. If the fumes give out a very sweet odour it indicates that the quicksilver is
being lost, and since this loosens the teeth, the smelters and others
standing by,
warned of the evil, turn their backs to the wind, which
drives the fumes in
the opposite direction; for this reason, the
building should be open around
the front and the sides, and exposed to
the wind. If these pots are made
of cast copper they last a long time in the fire. This process for reducing the
ores of quicksilver is used by most
people.
In a similar manner the antimony ore,
in upper pots which are twice
as large as the lower ones. Their size, however,
depends on the cakes, which have not the same
weight everywhere; for in
some places they are made to weigh six
where twenty. When the smelter has concluded his operation, he extin
guishes the
fire with water, removes the lids from the pots, throws earth mixed
with ash around and over them, and when they have cooled, takes out the
cakes from the pots.
Other methods for reducing quicksilver are given below.
Big-bellied
pots, having been placed in the upper rectangular open part
of a furnace,
are filled with the crushed ore. Each of these pots is covered with a lid
with a long
nozzle—commonly called a
they are
cemented. Each of the small earthenware vessels shaped like a
gourd receives two
of these nozzles, and these are likewise cemented. Dried
A—POTS. B—OPERCULA. C—NOZZLES. D—GOURD-SHAPED
EARTHENWARE VESSELS.
wood having been placed in the lower part of the
furnace and kindled, the
ore is heated until all the quicksilver has
risen into the operculum which is
over the pot; it then flows from the
nozzle and is caught in the earthenware
gourd-shaped vessel.
Others build a hollow vaulted chamber, of which the paved floor is made
concave toward the centre. Inside the thick walls of the chamber are the
furnaces. The doors through which the wood is put are in the outer part of the
same wall. They place the pots in the furnaces and fill them with crushed
ore, then
they cement the pots and the furnaces on all sides with lute, so that
none of the vapour may escape from them, and there is no entrance to
the
A—ENCLOSED CHAMBER. B—DOOR. C—LITTLE WINDOWS.
D—MOUTHS THROUGH THE
WALLS. E—FURNACE IN THE ENCLOSED
CHAMBER. F—POTS.
furnaces except through their mouths. Between the dome and the paved
floor they arrange green trees, then they
close the door and the little windows,
and cover them on all sides with
moss and lute, so that none of the quick
silver can exhale from the
chamber. After the wood has been kindled the
heat, and liking
the cold, it escapes to the leaves of the trees, which
have a cooling
power. When the operation is completed the smelter
extinguishes the fire, and
when all gets cool he opens the door and the
windows, and collects the
quicksilver, most of which, being heavy, falls of
its own accord from
the trees, and flows into the concave part of the floor;
if all should
not have fallen from the trees, they are shaken to make it fall.
The following is the fourth method of reducing ores of quicksilver.
A
larger pot standing on a tripod is filled with crushed ore, and over
the ore is
put sand or ashes to a thickness of two digits, and tamped;
then in
the mouth of this pot is inserted the mouth of another smaller
pot and
cemented with lute, lest the vapours are emitted. The ore heated by the fire
exhales the quicksilver, which, penetrating
through the sand or the ashes,
takes refuge in the upper pot, where
condensing into drops it falls back into
the sand or the ashes, from
which the quicksilver is washed and collected.
A—LARGER POT. B—SMALLER. C—TRIPOD. D—TUB IN WHICH THE
SAND IS WASHED.
The fifth method is not very unlike the fourth.
In the place of these
pots are set other pots, likewise of earthenware,
having a narrow bottom
and a wide mouth. These are nearly filled with crushed ore, which is likewise
covered with
ashes to a depth of two digits and tamped in. The pots are
liquid litharge, and on the lid are
placed heavy stones. The pots are set on
the furnace, and the ore is heated and similarly
exhales quicksilver, which
fleeing from the heat takes refuge in the
lid; on congealing there, it falls
back into the ashes, from which,
when washed, the quicksilver is collected.
A—POTS. B—LIDS. C—STONES. D—FURNACE.
By these five methods quicksilver may be made, and of these not one is
to be despised or repudiated; nevertheless, if the mine supplies a
great
abundance of ore, the first is the most expeditious and
practical, because a
large quantity of ore can be reduced at the same
time without great expense.
Bismuth
methods. First a small pit is dug in the dry ground; into this pulverised
charcoal is thrown and tamped in, and then it is dried with burning
charcoal. Afterward, thick dry pieces of beech wood are placed over the pit, and the
bismuth ore is thrown on it. As soon as the kindled wood burns, the heated
ore drips with bismuth,
which runs down into the pit, from which when cooled
the cakes are
removed. Because pieces of burnt wood, or often charcoal
and occasionally slag,
drop into the bismuth which collects in the pit, and
make it impure, it
is put back into another kind of crucible to be melted,
so that pure
cakes may be made. There are some who, bearing these things
in mind, dig a pit on a sloping
place and below it put a forehearth, into
which the bismuth continually
flows, and thus remains clean; then they
take it out with ladles and
pour it into iron pans lined inside with lute, and
make cakes of it. They cover such pits with flat stones, whose joints are
besmeared with a
lute of mixed dust and crushed charcoal, lest the joints
should absorb
the molten bismuth. Another method is to put the ore in
troughs made of fir-wood and placed
on sloping ground; they place small
firewood over it, kindling it when
a gentle wind blows, and thus the ore is
heated. In this manner the bismuth melts and runs down from the troughs
into a
pit below, while there remains slag, or stones, which are of a yellow
colour, as is also the wood laid across the pit. These are also sold.
A—PIT ACROSS WHICH WOOD IS PLACED. B—FOREHEARTH. C—LADLE.
D—IRON
MOULD. E—CAKES. F—EMPTY POT LINED WITH STONES
IN LAYERS. G—TROUGHS.
H—PITS DUG AT THE FOOT OF THE
TROUGHS. I—SMALL WOOD LAID OVER THE TROUGHS.
K—WIND.
Others reduce the ore in iron pans as next described.
They lay small
pieces of dry wood alternately straight and transversely
upon bricks, one and
a half feet apart, and set fire to it. Near it they put small iron pans lined
on the inside with lute, and full
of broken ore; then when the wind
blows the flame of the fierce fire
over the pans, the bismuth drips out of the
ore; wherefore, in order
that it may run, the ore is stirred with the tongs; but
when they
decide that all the bismuth is exuded, they seize the pans with
the
tongs and remove them, and pour out the bismuth into empty pans, and
by
turning many into one they make cakes. Others reduce the ore, when it is
not mixed with In this
case they make a pit and a crucible of crushed earth mixed with
pulverised
A—WOOD. B—BRICKS. C—PANS. D—FURNACE.
E—CRUCIBLE. F—PIPE.
G—DIPPING-POT.
charcoal, and
into it they put the broken ore, or the concentrates from
washing, from
which they make more bismuth. If they put in ore,
they reduce it with charcoal and small dried wood
mixed, and if concentrates,
they use charcoal only; they blow both
materials with a gentle blast from From the crucible is a small pipe through which the molten
bismuth runs
down into a dipping-pot, and from this cakes are made.
On a dump thrown up from the mines, other people construct a hearth
exposed to the wind, a foot high, three feet wide, and four and a half
feet
long. It is held together by four boards, and the whole is thickly coated at
the top with lute. On this hearth they first put small dried sticks of fir wood,
then over
them they throw broken ore; then they lay more wood over it,
and when
the wind blows they kindle it. In this manner the bismuth drips
out of the ore, and afterward the ashes
of the wood consumed by the fire and
the charcoals are swept away. The drops of bismuth which fall down into
the hearth are congealed by
the cold, and they are taken away with the
tongs and thrown into a
basket. From the melted bismuth they make
cakes in iron pans.
A—HEARTH IN WHICH ORE IS MELTED. B—HEARTH ON WHICH LIE DROPS OF
BISMUTH.
C—TONGS. D—BASKET. E—WIND.
Others again make a box eight feet long, four feet wide, and two feet high,
which they fill almost full of sand and cover with bricks, thus making
the hearth. The box has in the centre a wooden pivot, which turns in a hole
in two
beams laid transversely one upon the other; these beams are hard and
thick, are sunk into the ground, both ends are perforated, and through
fixed, and that the box may turn round, and
may be turned toward the wind
from whichever quarter of the sky it may
blow. In such a hearth they put
A—BOX. B—PIVOT. C—TRANSVERSE WOOD BEAMS. D—GRATE.
E—ITS FEET.
F—BURNING WOOD. G—STICK. H—PANS IN
WHICH THE BISMUTH IS MELTED.
I—PANS FOR MOULDS. K—CAKES.
L—FORK. M—BRUSH.
an iron grate, as long and wide as the box
and threequarters of a foot high;
it has six feet, and there are so
many transverse bars that they almost touch
one another. On the grate they lay pine-wood and over it broken ore, and over
this
they again lay pine-wood. When it has been kindled the ore melts, out
of which the bismuth drips
down; since very little wood is burned, this is the
most profitable
method of smelting the bismuth. The bismuth drips through
the grate on to the hearth, while the other
things remain upon the grate with
the charcoal. When the work is finished, the workman takes a stick from the
hearth and
overturns the grate, and the things which have accumulated on
it; with
a brush he sweeps up the bismuth and collects it in a basket, and
then
he melts it in an iron pan and makes cakes. As soon as possible after
it is cool, he turns the pans over, so that
the cakes may fall out, using for
this purpose a two-pronged fork of
which one prong is again forked. And
immediately afterward he returns to his labours.
END OF BOOK IX.
Questions as to the methods of smelting ores and
of obtaining metals I
discussed in Book IX. Following this, I should explain in what manner the
precious metals are
parted from the base metals, or
on the other hand the base metals from
the preciousFrequently two metals, occasionally more than
two, are melted out of one
ore, because in
nature generally there is some amount of gold in
silver and in copper, and some silver in gold, copper,
lead, and
iron; likewise some copper in gold, silver, lead, and iron, and
some
lead in silver; and lastly, some iron in copperBut I will begin with
gold.
Gold is parted from silver, or likewise the latter from the former, whether
it be mixed by nature or by art, by means of
which consist of almost the same things as this
In order to preserve the
sequence, I will first speak of the
ingredients of which this
of the method of making it, then of the manner in
which gold is parted from
silver or silver from gold. Almost all these ingredients contain vitriol or
alum, which, by
themselves, but much more when joined with saltpetre, are
powerful to
part silver from gold. As to the other things that are added to
them, they cannot individually
by their own strength and nature separate
those metals, but joined they
are very powerful. Since there are many
combinations, I will set out a few. In the first, the use of which is common
and general, there is one The second contains two
petre, and as much
spring or river water by weight as will pass away whilst
the vitriol is
being reduced to powder by the fire. The third consists of four
and a half The fourth consists of two
as many
of a The fifth is composed of one
of spring water. The sixth consists of four
saltpetre, one of alum, one
fierce furnace are easily liquefied by fire of the
third order, and one and a
half The seventh is made of two
and a half
which
when thrown into a glowing furnace are easily liquefied by fire of the
third order, and five-sixths of a The eighth is made of
two
half
silver; and to each separate The
ninth contains two
likewise one
of spring water. Only the tenth lacks vitriol and alum, but it contains three
are easily liquefied by fire of the third
order, half a
of
All the vitriol from which the
powder in the
following way. It is thrown into an earthen crucible lined on
the inside with litharge,
and heated until it melts; then it is stirred with a
copper wire, and
after it has cooled it is pounded to powder. In the same
manner saltpetre melted by the fire is pounded to powder
when it has cooled. Some indeed place alum upon an iron plate, roast it, and make it into
powder.
Although all these
impurities, yet there are
certain compositions which possess singular power.
a For each
of spring or river water, as to which, since this
pertains to all these com
pounds, it is sufficient to have
mentioned once for all. The second com
position is made from one
vitriol, lime, alum, ash which the dyers of wool
use, one quarter of a
of verdigris, and one and a half The third consists of three
baked
bricks. The fourth consists of one
and half a
The furnace in which
two feet long and wide, and as many feet
high and a half besides. It is
covered with iron plates supported with iron rods; these plates
are smeared
on the top with lute, and they have in the centre a round
hole, large enough to
hold the earthen vessel in which the glass
ampulla is placed, and on each side of
the centre hole are two small
round air-holes. The lower part of the furnace,
in order to hold the burning charcoal,
has iron plates at the height of a palm,
likewise supported by iron
rods. In the middle of the front there is the
mouth, made for the purpose of
putting the fire into the furnace; this mouth
is half a foot high and
wide, and rounded at the top, and under it is the
draught opening. Into the earthen vessel set over the hole is placed clean
sand a digit
deep, and in it the glass ampulla is set as deeply as it is smeared
with lute. The lower quarter is smeared eight or ten times with nearly liquid
lute,
each time to the thickness of a blade, and each time it is dried again,
until it has become as thick as the thumb; this kind of lute is well
beaten
with an iron rod, and is thoroughly mixed with hair or cotton
thread, or with
wool and salt, that it should not crackle. The many things of which the
compounds are made must not fill the
ampulla completely, lest when boiling
they rise into the operculum. The operculum is likewise made of glass,
and is closely joined to the
ampulla with linen, cemented with wheat flour
and white of egg
moistened with water, and then lute free from salt is spread
over that
part of it. In a similar way the spout of the operculum is joined
by linen covered
with lute to another glass ampulla which receives the distilled A kind of thin iron nail or small wooden peg, a little thicker than a
needle, is fixed in this joint, in order that when air seems necessary
to the
artificer distilling by this process he can pull it out; this is
necessary when
too much of the vapour has been driven into the upper
part. The four air
holes which, as I have said, are on the top of the
furnace beside the large
hole on which the ampulla is placed, are
likewise covered with lute.
A—FURNACE. B—ITS ROUND HOLE. C—AIR-HOLES. D—MOUTH OF
THE FURNACE.
E—DRAUGHT OPENING UNDER IT. F—EARTHENWARE
CRUCIBLE. G—AMPULLA.
H—OPERCULUM. I—ITS SPOUT.
K—OTHER AMPULLA. L—BASKET IN WHICH THIS IS
USUALLY PLACED
LEST IT SHOULD BE BROKEN.
All this preparation having been accomplished in order, and the
ingredients placed in the ampulla, they are gradually heated over
burning
charcoal until they begin to exhale vapour and the ampulla is
seen to trickle
with moisture. But when this, on account of the rising of the vapour, turns
red, and
the
work with the utmost care, lest
the drops should fall at a quicker rate than
one for every five
movements of the clock or the striking of its bell, and
not slower than
one for every ten; for if it falls faster the glasses will be
broken,
and if it drops more slowly the work begun cannot be completed
within
the definite time, that is within the space of twenty-four hours. To
prevent the first accident, part of the coals are extracted by means
of an iron
implement similar to pincers; and in order to prevent the
second happening,
small dry pieces of oak are placed upon the coals,
and the substances in the
ampulla are heated with a sharper fire, and
the air-holes on the furnace
are re-opened if need arise. As soon as the drops are being distilled,
the glass ampulla which
receives them is covered with a piece of linen
repelled. When the ingredients have been heated and the ampulla in which
they were
placed is whitened with moisture, it is heated by a fiercer fire until
all the drops have been distilledAfter the furnace has cooled, the
filtered and poured into a small glass ampulla,
and into the same is put half
a This is poured into the ampulla containing all the rest of the
soon as the
lees have sunk to the bottom the
reserved for use.
Gold is parted from silver by the following method
The alloy, with lead
added to it, is first heated in a cupel until all
the lead is exhaled, and eight
if there is more
copper in it, the silver separated from the gold soon unites
with it
again. Such molten silver containing gold is formed into granules,
being
stirred by means of a rod split at the lower end, or else is poured into an
iron mould, and when cooled is made into thin leaves. As the process of
making granules from argentiferous gold demands
greater care and diligence than
making them from any other metals, I
will now explain the method briefly. The
alloy is first placed in a crucible, which is then covered with a
lid and placed
in another earthen crucible containing a few ashes. Then they are placed
in the furnace, and after they are surrounded by
charcoal, the fire is blown
by the blast of a bellows, and lest the
charcoal fall away it is surrounded
by stones or bricks. Soon afterward charcoal is thrown over the upper
crucible and covered
with live coals; these again are covered with charcoal,
so that the
crucible is surrounded and covered on all sides with it. It
is necessary to heat the crucibles with charcoal for the space of
half an hour or
a little longer, and to provide that there is no
deficiency of charcoal, lest the
alloy become chilled; after this the
air is blown in through the nozzle of the
bellows, that the gold may
begin to melt. Soon afterward it is turned
round, and a test is quickly taken to see
whether it be melted, and if it is
melted, fluxes are thrown into it;
it is advisable to cover up the crucible
again closely that the
contents may not be exhaled. The contents are heated
together for as long as it would take to walk
fifteen paces, and then the
crucible is seized with tongs and the gold
is emptied into an oblong vessel
containing very cold water, by pouring
it slowly from a height so that the
granules will not be too big; in
proportion as they are lighter, more fine
and more irregular, the
better they are, therefore the water is frequently
stirred with a rod
split into four parts from the lower end to the middle.
The leaves are cut into small pieces, and they or the silver granules are
put into a glass ampulla, and the
digit above
the silver. The ampulla is covered with a bladder or with waxed
linen, lest the
contents exhale. Then it is heated until the silver is dissolved,
the indication of which
is the bubbling of the The gold remains in the
bottom, of a blackish colour, and the silver
mixed with the Some pour the latter into a copper bowl and pour into it cold water, which
immediately congeals the silver; this they take out and dry, having
poured
off the They heat the dried silver in an earthenware crucible until
it melts,
and when it is melted they pour it into an iron mould.
The gold which remains in the ampulla they wash with warm water,
filter,
dry, and heat in a crucible with a little
borax, and
when it is melted they likewise pour it into an iron mould.
Some workers, into an ampulla which contains gold and silver and the
valens
poured, throw fine leaves of
black lead and copper; by this means the gold
adheres to the lead and
the silver to the copper, and separately the lead
from the gold, and
separately the copper from the silver, are parted in a
cupel. But no method is approved by us which loses the
gold from silver, for
it might be used again
A glass ampulla, which bulges up inside at the bottom like a cone, is
covered on the lower part of the outside with lute in the way explained
above,
and into it is put silver bullion weighing three and a half
Roman The
placed in
sand contained in an earthen vessel, or in a box, that it may be
warmed
with a gentle fire. Lest the
ampulla is plastered on all sides with lute,
and it is covered with a glass
operculum, under whose spout is placed
another ampulla which receives the
distilled drops; this receiver is
likewise arranged in a box containing sand. When the contents are heated it reddens, but when the redness no
longer
appears to increase, it is taken out of the vessel or box and shaken;
by this motion the
done two or three times
before other
concluded, and much less When the first charge has all
been distilled, as much silver as at first
is again put into the ampulla, for if
too much were put in at once, the
gold would be parted from it with difficulty. Then the second
ampulla may be of
equal temperature, so that the latter may not be cracked
by the cold;
also if a cold wind blows on it, it is apt to crack. Then the third
say more
of burned brick. The artificer keeps in hand two
stronger than the other; the
stronger is used at first, then the less strong,
then at the last again
the stronger. When the gold becomes of a reddish
yellow colour, spring water is poured
in and heated until it boils. The gold is
washed four times and then heated in the crucible until it
melts. The water
with which it was washed is put back, for there is a little
silver in it; for
this reason it is poured into an ampulla and heated,
and the drops first distilled
are received by one ampulla, while those
which come later, that is to say
when the operculum begins to get red,
fall into another. This latter
useful for testing the gold, the former for washing it; the former may
also
be poured over the ingredients from which the
The
an ampulla wide at
the base, the top of which is also smeared with lute and
covered by an
operculum, and is then boiled as before in order that it may be
separated from the silver. If there be so much
A—AMPULLAE ARRANGED IN THE VESSELS. B—AN AMPULLA STANDING UPRIGHT
BETWEEN
IRON RODS. C—AMPULLAE PLACED IN THE SAND WHICH IS
CONTAINED IN A BOX, THE
SPOUTS OF WHICH REACH FROM THE OPERCULA INTO
AMPULLAE PLACED UNDER THEM.
D—AMPULLAE LIKEWISE PLACED IN SAND
WHICH IS CONTAINED IN A BOX, OF WHICH THE
SPOUT FROM THE OPERCULA
EXTENDS CROSSWISE INTO AMPULLAE PLACED UNDER THEM.
E—OTHER
AMPULLAE RECEIVING THE DISTILLED
CONTAINED IN THE
LOWER BOXES. F—IRON TRIPOD, IN WHICH THE AMPULLA IS USUALLY
PLACED WHEN THERE ARE NOT MANY PARTICLES OF GOLD TO BE PARTED FROM THE
SILVER.
G—VESSEL.
rises into the operculum, there is put into
the ampulla one lozenge or two;
these are made of soap, cut into small
pieces and mixed together with
powdered argol, and then heated in a pot
over a gentle fire; or else the
contents are stirred with a hazel twig
split at the bottom, and in both cases
the When the powerful vapour
appears, the But,
lest the vapours should escape from the ampulla and the operculum
in that
part where their mouths communicate, they are entirely sealed
all round. The
put into
the furnace so that the live coals touch the vessel. The ampulla is
taken out as soon as all the
by the heat of the fire, alone remains in it; the silver
is shaken out and put
in an earthenware crucible, and heated until it
melts. The molten glass is
extracted with an iron rod curved at the lower end,
and the silver is made The glass extracted from the crucible is ground to powder, and
to this
are added litharge, argol, glass-galls, and saltpetre, and they are
melted in an earthen crucible. The button that settles is transferred to the
cupel and re-melted.
If the silver was not sufficiently dried by the heat of the fire, that which
is contained in the upper part of the ampulla will appear black; this
when
melted will be consumed. When the lute, which was smeared round the
lower part of the ampulla,
has been removed, it is placed in the crucible and
is re-melted, until
at last there is no more appearance of black
If to the first
must be poured in before
the powerful vapours appear, and the
the oily substance, and the operculum
becomes red; for he who pours in the
out and the glass breaks. If the ampulla breaks when the gold is being parted
from the silver or
the silver from the
sand or the lute or the bricks, whereupon, without any delay, the
red hot coals
should be taken out of the furnace and the fire
extinguished. The sand and
bricks after being crushed should be thrown into a copper
vessel, warm water. should be poured over them, and they should be put aside for the space of
twelve hours; afterward the water should be strained through a canvas,
and
the canvas, since it contains silver, should be dried by the heat
of the sun or
the fire, and then placed in an earthen crucible and
heated until the silver
melts, this being poured out into an iron
mould. The strained water should
be poured into an ampulla and separated from
the silver, of which it contains
a minute portion; the sand should be
mixed with litharge, glass-galls,
argol, saltpetre, and salt, and
heated in an earthen crucible. The button
which settles at the bottom should be transferred to a cupel,
and should
be re-melted, in order that the lead may be separated from
the silver. The
lute, with lead added, should be heated in an earthen crucible, then
re-melted in a cupel.
We also separate silver from gold by the same method when we assay
them. For this purpose the alloy is first rubbed against a touchstone, in
order to learn what proportion of silver there is in it; then as much
silver
as is necessary is added to the argentiferous gold, in a
must
be less than a After lead has been added, it is melted in a cupel until the lead and the
copper have exhaled, then the alloy of gold with silver is flattened
out, and
little tubes are made of the leaves; these are put into a
glass ampulla,
and strong The tubes after
this are absolutely pure, with the exception of only a
quarter of a
which is silver; for only this much silver remains in eight
As great expense is incurred in parting the metals by the methods that
I
have explained, as night vigils are necessary when
and as generally much
labour and great pains have to be expended on this
matter, other
methods for parting have been invented by clever men, which
are less
costly, less laborious, and in which there is less loss if through
care
lessness an error is made. There are three methods, the first performed with
sulphur, the second
with antimony, the third by means of some compound
which consists of
these or other ingredients.
In the first method,
crucible and made into granules. For every
a sixth of a
when
crushed, is sprinkled over the moistened granules, and then they are put
into a new carthen pot of the capacity of four
if there is an abundance of granules. The pot, having been filled, is covered
with an earthen lid and smeared
over, and placed within a circle of fire set one
and a half feet
distant from the pot on all sides, in order that the sulphur
added to
the silver should not be distilled when melted. The pot is opened,
A—POT. B—CIRCULAR FIRE. C—CRUCIBLES. D—THEIR LIDS.
E—LID OF THE POT.
F—FURNACE. G—IRON ROD.
the
black-coloured granules are taken out, and afterward thirty-three
of these granules
are placed in an earthen crucible, if it has such capacity. For every
copper, if
each
a quarter of a If,
however, the silver contains five-sixths of a
and a half of copper, then
there are weighed out a quarter of a
granules. If a
of copper, or
eleven-twelfths and a
copper, then are weighed out a quarter of a Lastly, if there is only pure silver, then as much
as a third of a Half
of these copper granules are added soon afterward to the
black-coloured
silver granules. The crucible should be tightly covered and smeared over
with lute, and
placed in a furnace, into which the air is drawn through the
draught-holes. As soon as the silver is melted, the crucible is opened, and
there is
placed in it a heaped ladleful more of granulated copper, and also
a
heaped ladleful of a powder which consists of equal parts of litharge, of
granulated lead, of salt, and of glass-galls; then the crucible is
again covered
with the lid. When the copper granules are melted, more are put in, together
with the
powder, until all have been put in.
A little of the regulus is taken from the crucible, but not from the gold
lump which has settled at the bottom, and a
the
cupels, which contain an
of these cupels. In this way half a
As soon as
the lead and copper have been separated from the silver, a
third of it is
thrown into a glass ampulla, and By this
method is shown whether the sulphur has parted all the gold from
the silver,
or not. If one wishes to know the size of the gold lump which has settled
at the
bottom of the crucible, an iron rod moistened with water is covered
with chalk, and when the rod is dry it is pushed down straight into the
crucible, and the rod remains bright to the height of the gold lump;
the
remaining part of the rod is coloured black by the regulus, which
adheres to
the rod if it is not quickly removed.
If when the rod has been extracted the gold is observed to be
satisfactorily parted from the silver, the regulus is poured out, the
gold
button is taken out of the crucible, and in some clean place the
regulus is
chipped off from it, although it usually flies apart. The lump itself is reduced
to granules, and for every
each of crushed sulphur and of granular copper, and all are placed
together
in an earthen crucible, not into a pot. When they are melted, in order that
the gold may more quickly settle at
the bottom, the powder which I have
mentioned is added.
Although minute particles of gold appear to scintillate in the regulus
of copper and silver, yet if all that are in a
single
sesterce, then the sulphur has satisfactorily parted the gold from the
back again into the earthen crucible, and it is
not advantageous to add sulphur,
but only a little copper and powder,
by which method a gold lump is again
made to settle at the bottom; and
this one is added to the other button which
is not rich in gold.
When gold is parted from sixty-six
and sulphur regulus weighs one hundred and thirty-two To separate
the copper from the silver we require five hundred
less, with which the regulus is melted in the second furnace. In this
manner litharge and hearth-lead are made, which are re-smelted
in the first
furnace. The cakes that are made from these are placed in the third furnace,
so
that the lead may be separated from the copper and used again, for it
contains very little silver. The crucibles and their covers are crushed, washed,
and the sediment is
melted together with litharge and hearth-lead.
Those who wish to separate all the silver from the gold by this method
leave one part of gold to three of silver, and then reduce the alloy to
granules. Then they place it in an ampulla, and by pouring
it, part the gold from the
silver, which process I explained in Book VII.
If sulphur from the lye with which
enough to float an egg thrown into it, and is boiled until it no longer
emits
fumes, and melts when placed upon glowing coals, then, if such
sulphur is
thrown into the melted silver, it parts the gold from
it.
Silver is also parted from gold by means of
If in a
gold there
are seven, or six, or five double
of
not consume the gold, it is melted with
copper in a red hot earthern crucible. If the gold contains some portion of copper, then to eight
silver. The gold is first placed in a red hot earthen crucible, and when
melted
it swells, and a little
short space
of time, when this has melted, it likewise again swells, and
when this
occurs it is advisable to put in all the remainder of the
and to cover the
crucible with a lid, and then to heat the mixture for the
time required
to walk thirty-five paces. Then it is at once poured out into
an iron pot, wide at the top and
narrow at the bottom, which was first
heated and smeared over with
tallow or wax, and set on an iron or wooden
block. It is shaken violently, and by this agitation the gold lump settles
to
the bottom, and when the pot has cooled it is tapped loose, and is again
melted four times in the same way. But each time a less weight of
is added to the gold, until finally only twice as
much
there is gold, or a little more; then the gold lump is melted in a
cupel. The
time a gold
lump settles, so that there are three or four gold lumps, and
these are
all melted together in a cupel.
To two
and one
where a lump likewise settles at the bottom; this
lump is melted in the
cupel. Finally, the
in which, after all the rest
has been consumed by the fire, the silver alone
remains. If the
and glass-galls, before
it is melted in the cupel, part of the silver is consumed,
and is
absorbed by the ash and powder of which the cupel is made.
The crucible in which the gold and silver alloy are melted with
and
also the cupel, are placed in a furnace, which is usually of the kind
A—FURNACE IN WHICH THE AIR IS DRAWN IN THROUGH HOLES.
B—GOLDSMITH'S FORGE.
C—EARTHEN CRUCIBLES. D—IRON
POTS. E—BLOCK.
in which the air is drawn in through holes; or else
they are placed in a gold
smith's forge.
Just as
parted the gold, shows us
whether all has been separated or whether
particles of gold remain in
the silver; so do certain ingredients, if placed in
the pot or crucible
“alternately” with the gold, from which the silver has
been
parted by
separated or not.
We use cements
so ingeniously and admirably from gold. There are various cements.
Some
petre, half an The bricks
or tiles from which the dust is made must be composed of
fatty clays, free from
sand, grit, and small stones, and must be
moderately burnt and very old.
Another cement is made of a
Another cement is made
of a
saltpetre, an Another
has one
sixth of a Another is made of half a
brick dust, a third of a
one Another consists of a
refined salt, a sixth of white vitriol
half
an Another is made of one and a third
dust, a
a sixth and half an Another contains
a
Those ingredients above are peculiar to each cement, but what follows
is
common to all. Each of the ingredients is first separately crushed to
powder; the
bricks are placed on a hard rock or marble, and crushed with an
iron
implement; the other things are crushed in a mortar with a pestle;
each
is separately passed through a sieve. Then they are all mixed together,
and are moistened with vinegar in
which a little sal-ammoniac has been
dissolved, if the cement does not
contain any. But some workers, however,
prefer to moisten the gold granules or
gold-leaf instead.
The cement should be placed, alternately with the gold, in new and clean
pots in which no water has ever been poured. In the bottom the cement is
levelled with an iron implement, and
afterward the gold granules or leaves
are placed one against the other,
so that they may touch it on all sides; then,
again, a handful of the
cement, or more if the pots are large, is thrown in and
levelled with
an iron implement; the granules and leaves are laid over this
in the
same manner, and this is repeated until the pot is filled. Then it is
covered with a lid, and the place where they join is smeared
over with
artificial lute, and when this is dry the pots are placed in
the furnace.
The furnace has three chambers, the lowest of which is a foot high; into
this lowest chamber the air penetrates through an opening, and into it
the
A—FURNACE. B—POT. C—LID. D—AIR-HOLES.
form a grating. The middle chamber is two feet high, and the wood is pushed
in through
its mouth. The wood ought to be oak, holmoak, or turkey-oak,
for from these the
slow and lasting fire is made which is necessary for this
operation. The upper chamber is open at the top so that the pots, for which
it has
the depth, may be put into it; the floor of this chamber consists of iron
rods, so strong that they may bear the weight of the pots and the heat
of the
fire; they are sufficiently far apart that the fire may
penetrate well and may
heat the pots. The pots are narrow at the bottom, so that the fire entering
into the
space between them may heat them; at the top the pots are wide,
so that
they may touch and hold back the heat of the fire. The upper part
of the furnace is closed in with bricks not very thick,
or with tiles and lute,
and two or three air-holes are left, through
which the fumes and flames may
escape.
The gold granules or leaves and the cement, alternately placed in the pots,
are heated by a gentle fire, gradually increasing for twenty-four
hours, if the
furnace was heated for two hours before the full pots
were stood in it, and if
this was not done, then for twenty-six hours. The fire should be increased
in such a manner that the pieces of gold
and the cement, in which is the
potency to separate the silver and
copper from the gold, may not melt, for in
this case the labour and
cost will be spent in vain; therefore, it is ample to
have the fire hot
enough that the pots always remain red. After so many
hours all the burning wood should be drawn out of the
furnace. Then the
refractory bricks or tiles are removed from the top of the
furnace, and the
glowing pots are taken out with the tongs. The lids are removed, and
if there is time it is well to allow the gold
to cool by itself, for then there is
less loss; but if time cannot be
spared for that operation, the pieces of gold
are immediately placed
separately into a wooden or bronze vessel of water
and gradually
quenched, lest the cement which absorbs the silver should
exhale it. The pieces of gold, and the cement adhering to them, when cooled
or
quenched, are rolled with a little mallet so as to crush the lumps and free
the gold from the cement. Then they are sifted by a fine sieve, which is
placed over a bronze
vessel; in this manner the cement containing the
silver or the copper
or both, falls from the sieve into the bronze vessel, and the
gold
granules or leaves remain on it. The gold is placed in a vessel and
again rolled with the little mallet,
so that it may be cleansed from the cement
which absorbs silver and
copper.
The particles of cement, which have dropped through the holes of the
sieve into the bronze vessel, are washed in a bowl, over a wooden tub,
being
shaken about with the hands, so that the minute particles of gold
which have
fallen through the sieve may be separated. These are again washed in a
little vessel, with warm water, and scrubbed
with a piece of wood or a twig
broom, that the moistened cement may be
detached. Afterward all the gold
is again washed with warm water, and collected
with a bristle brush, and should
be washed in a copper full of holes,
under which is placed a little vessel. Then it is necessary to put the gold on an iron plate, under which is a
vessel,
Finally, it is placed in a bowl, and, when
dry, the granules or leaves
are rubbed against a touchstone at the same time
as a touch-needle, and
considered carefully as to whether they be pure or
alloyed. If they are not pure enough, the granules or the leaves, together
with
the cement which attracts silver and copper, are arranged alternately
in layers in the same manner, and again heated; this is done as often
as is
necessary, but the last time it is heated as many hours as are
required to
cleanse the gold.
Some people add another cement to the granules or leaves.
This cement
lacks the ingredients of metalliferous origin, such as
verdigris and vitriol, for
if these are in the cement, the gold usually
takes up a little of the base metal;
or if it does not do this, it is
stained by them. For this reason some very
rightly never make use of cements containing
these things, because brick
dust and salt alone, especially rock salt,
are able to extract all the silver and
copper from the gold and to
attract it to themselves.
It is not necessary for coiners to make absolutely pure gold, but to heat
it only until such a fineness is obtained as is needed for the gold
money which
they are coining.
The gold is heated, and when it shows the necessary golden yellow colour
and is wholly pure, it is melted and made into bars, in which case they
are
either prepared by the coiners with
borax, or are prepared with salt of lye made from the ashes of ivy or
of
other salty herbs.
The cement which has absorbed silver or copper, after water has been
poured over it, is dried and crushed, and when mixed with hearth-lead
and
de-silverized lead, is smelted in the blast furnace. The alloy of silver and
lead, or of silver and copper and lead, which
flows out, is again melted in the
cupellation furnace, in order that
the lead and copper may be separated from
the silver. The silver is finally thoroughly purified in the refining furnace,
and
in this practical manner there is no silver lost, or only a minute
quantity.
There are besides this, certain other cements
silver, composed of sulphur,
One of these
compounds consists of half an
and reduced to powder, a sixth of refined salt, a third of
one
is prepared as follows: it is first crushed to powder, then it is
heated
for six hours in sharp vinegar, and finally poured into a vessel
and washed
with warm water; then that which settles at the bottom of
the vessel is
dried. To refine the salt it is placed in river water and boiled, and again
evaporated. The second compound contains one
to fire) and two The third compound is made from one
a The fourth compound
consists of one
argol, and half a The fifth
compound has equal proportions of sulphur (not exposed to the
fire), sal
ammoniac, saltpetre, and verdigris.
The silver which contains some portion of gold is first melted with
lead
in an earthen crucible, and they are heated together until the silver
exhales the lead. If there was a
lead. Then the silver is sprinkled with two
warmed and lined with tallow, and then violently
shaken. The rest is per
formed according to the process I have already
explained.
Gold may be parted without injury from silver goblets and from other
gilt vessels and articles
sal-ammoniac and half
a part of sulphur. The gilt goblet or other article
is smeared with oil, and the powder is
dusted on; the article is seized in the
hand, or with tongs, and is
carried to the fire and sharply tapped, and by this
means the gold
falls into water in vessels placed underneath, while the
goblet remains
uninjured.
Gold is also parted from silver on gilt articles by means of quicksilver.
This is poured into an earthen crucible, and so warmed by the fire that the
finger can bear the heat when dipped into it; the silver-gilt objects
are
placed in it, and when the quicksilver adheres to them they are
taken out
and placed on a dish, into which, when cooled, the gold
falls, together with the
quicksilver. Again and frequently the same silver-gilt object is placed in
heated
quicksilver, and the same process is continued until at last no
more
gold is visible on the object; then the object is placed in the fire, and
the quicksilver which adheres to it is exhaled. Then the artificer takes a hare's
foot, and brushes up into a dish the
quicksilver and the gold which have
cotton or
into a soft leather; the quicksilver is squeezed through one or the
other into another dish.
when collected is placed
in a piece of charcoal hollowed out, and is heated
until it melts, and
a little button is made from it. This button is heated with
a little
vessel, by which method the gold
settles at the bottom, and the
seen to be on
the top; then the work is completed. Finally, the gold
button is put in a hollowed-out brick and placed in
the fire, and by this
method the gold is made pure. By means of the above methods gold is parted
from silver and also silver
from gold.
Now I will explain the methods used to separate copper from gold
alum, saltpetre, and sulphur not exposed to the fire, and half
a
ammoniac; these ingredients when crushed are heated with one
part of lye made
from the ashes used by wool dyers, one part of
unslaked lime, and four
parts of beech ashes. The ingredients are boiled in the lye until the whole
has been
dissolved. Then it is immediately dried and kept in a hot place,
lest it turn into
oil; and afterward when crushed, a
with it. With each
of the copper is gradually
sprinkled into a hot crucible, and it is stirred
rapidly and frequently
with an iron rod. When the crucible has cooled and
been broken up, the button of gold is
found.
The second method for parting is the following.
Two
not exposed to the fire, and four
a sixth of a
made of lead, and twice
as much copper containing gold; they are heated
together in an earthen
crucible until they melt. When cooled, the button is
taken out and purged of slag. From this button they again make granules,
to a third of a
have spoken, and they are placed in alternate layers
in the crucible; it is
well to cover the crucible and to seal it up,
and afterward it is heated over a
gentle fire until the granules melt. Soon afterward, the crucible is taken off
the fire, and when it is cool
the button is extracted. From this, when purified
and again melted down, the third granules are
made, to which, if they weigh
a sixth of a
and they are heated in the same manner, and the button of gold
settles at the
bottom of the crucible.
The third method is as follows.
From time to time small pieces of
sulphur, enveloped in or mixed with
wax, are dropped into six
molten copper, and consumed; the sulphur
weighs half an Then one and a half
into the same
copper and likewise consumed; then again half an
lead-ash enveloped in wax, or of minium made from red-lead. Then imme
diately the copper is taken out, and to the gold button,
which is now mixed
with only a little copper, they add
these are heated together until the
together with lead of half the weight of the button,
are heated in a cupel.
blackish colour settled in it, it
is melted with a little of the
which the Moors call borax; if too pale, it is
melted with
acquires its own golden-yellow colour. There are some who take out the
molten copper with an iron ladle and
pour it into another crucible, whose
aperture is sealed up with lute,
and they place it over glowing charcoal,
and when they have thrown in
the powders of which I have spoken, they
stir the whole mass rapidly
with an iron rod, and thus separate the gold
from the copper; the
former settles at the bottom of the crucible, the latter
floats on the
top. Then the aperture of the crucible is opened with the
red-hot tongs, and
the copper runs out. The gold which remains is re-heated
with
in a cupel with a fourth part of lead, and
then quenched.
The fourth method is to melt one and a third
with a sixth of a
the inside with tallow or
gypsum; and to this is added a powder consisting of
half an
and a half of The fifth method consists of placing in a crucible
one
over a fiercer one. The sixth method consists in heating together a
the copper and one-sixth of a
The
seventh method consists of heating together a
each of
iron scales and filings, salt, The eighth
method consists of heating together one The
ninth method consists of placing in one
much
pounded sulphur, not exposed to the fire, and of stirring it rapidly
with an iron rod; the lump is ground to powder, into which quicksilver
is poured, and this attracts to itself the gold.
Gilded copper articles are moistened with water and placed on the fire,
and when they are glowing they are quenched with cold water, and the
gold
is scraped off with a brass rod. By these practical methods gold is separated
from copper.
Either copper or lead is separated from silver by the methods which I
will now explain.
in the works in which
the gold or silver ores or alloys are smelted. The
middle wall of such a building is twenty-one feet long and fifteen
feet high, and
from this a front wall is distant fifteen feet toward
the river; the rear wall
fourteen feet high; a
transverse wall extends from the end of the front wall to
the end of
the rear wall; then fifteen feet back a second transverse wall
is built
out from the front wall to the end of the middle wall. In that space
which is between those two transverse walls are set up the
stamps, by means
of which the ores and the necessary ingredients for
smelting are broken up. From the further end of the front wall, a third transverse wall leads to the
other end of the middle wall, and from the same to the end of the rear
wall. The space between the second and third transverse walls, and between the
rear and middle long walls, contains the cupellation furnace, in which
lead The vertical wall of its chimney is
erected upon the middle wall, and
the sloping chimney-wall rests on the
beams which extend from the
second transverse wall to the third; these are
so located that they are
at a distance of thirteen feet from the middle long
wall and four from
the rear wall, and they are two feet wide and thick. From the ground up to the roof-beams is twelve feet, and lest the sloping
chimney-wall should fall down, it is partly supported by means of many
iron rods, and partly by means of a few tie-beams covered with lute,
which
extend from the small beams of the sloping chimney-wall to the
beams of the
vertical chimney-wall. The rear roof is arranged in the same way as the roof
In the space between the middle and
the front long walls and between the
second
the bellows, the machinery for depressing and the
instrument for raising them. A drum on the axle of a water-wheel has rundles which turn the toothed
drum of an axle, whose long cams depress the levers of the bellows, and
also
another toothed drum on an axle, whose cams raise the tappets of
the stamps,
but in the opposite direction. So that if the cams which depress the levers
of the bellows turn from
north to south, the cams of the stamps turn from
south to north.
Lead is separated from gold or silver in a cupellation furnace, of
which
the structure consists of rectangular stones, of two interior walls of which
the one intersects the other transversely, of a round sole, and of a
dome. Its
crucible is made from powder of earth and ash; but I will first
speak of the
structure and also of the rectangular stones. A circular wall is built four
feet and three palms high, and one foot
thick; from the height of two feet
and three palms from the bottom, the
upper part of the interior is cut away
to the width of one palm, so
that the stone sole may rest upon it. There are
usually as many as fourteen stones; on the outside they are a
foot and a
palm wide, and on the inside narrower, because the inner
circle is much
smaller than the outer; if the stones are wider, fewer
are required, if
narrower more; they are sunk into the earth to a depth
of a foot and a palm. At the top each one is joined to the next by an iron staple, the points of
which are embedded in holes, and into each hole is poured molten lead. This
stone structure has six air-holes near the ground, at a height of a
foot above
the ground; they are two feet and a palm from the bottom of
the stones;
each of these air-holes is in two stones, and is two palms
high, and a palm and
three digits wide. One of them is on the right side, between the wall which
protects the
main wall from the fire, and the channel through which the
litharge
flows out of the furnace crucible; the other five air-holes are
distributed all round at equal distances apart; through these escapes
the
moisture which the earth exhales when heated, and if it were not
for these
openings the crucible would absorb the moisture and be
damaged. In such a
case a lump would be raised, like that which a mole throws up
from the earth,
and the ash would float on the top, and the crucible
would absorb the silver-lead
alloy; there are some who, because of
this, make the rear part of the structure
entirely open. The two inner walls, of which one intersects the other, are
built of
bricks, and are a brick in thickness. There are four air-holes in
these, one in each part, which are about one
digit's breadth higher and wider
than the others. Into the four compartments is thrown a wheelbarrowful
of slag, and over
this is placed a large wicker basket full of charcoal dust. These walls extend a cubit above the ground, and on these, and on the ledge
cut in the rectangular stones, is placed the stone sole; this sole is a
palm and
three digits thick, and on all sides touches the rectangular
stones; if there
are any cracks in it they are filled up with fragments
of stone or brick. The
front part of the sole is sloped so that a channel can be made,
through which Copper plates are placed on this part of the sole-stone
so that the
silver-lead or other alloy may be more rapidly heated.
A dome which has the shape of half a sphere covers the crucible.
It con
sists of iron bands and of bars and of a lid. There are three bands, each about
a palm wide and a digit thick; the
lowest is at a distance of one foot from the
middle one, and the middle
one a distance of two feet from the upper one. Under them are eighteen iron bars fixed by iron rivets; these bars are of
the same width and thickness as the bands, and they are of such a
length, that
curving, they reach from the lower band to the upper, that
is two feet and
three palms long, while the dome is only one foot and
three palms high. All
the bars and bands of the dome have iron plates fastened on the
underside
with iron wire. In addition, the dome has four apertures; the rear one,
which is
situated opposite the channel through which the litharge flows out,
is
two feet wide at the bottom; toward the top, since it slopes gently, it is
narrower, being a foot, three palms, and a digit wide; there is no bar
at
this place, for the aperture extends from the upper band to the
middle one,
but not to the lower one. The second aperture is situated above the
A—RECTANGULAR STONES. B—SOLE-STONE. C—AIR-HOLES.
D—INTERNAL WALLS.
E—DOME. F—CRUCIBLE. G—BANDS.
H—BARS. I—APERTURES IN THE DOME.
K—LID OF THE DOME.
L—RINGS. M—PIPES. N—VALVES. O—CHAINS.
at the top; and there is likewise no bar at this
point; indeed, not only does
the bar not extend to the lower band, but
the lower band itself does not
extend over this part, in order that the
master can draw the litharge out
of the crucible. There are besides, in the wall which protects the principal
wall against
the heat, near where the nozzles of the bellows are situated,
two
apertures, three palms wide and about a foot high, in the middle
of
which two rods descend, fastened on the inside with plates. Near these apertures are placed the nozzles of the bellows, and through
the apertures extend the pipes in which the nozzles of the bellows are
set. These pipes are made of iron plates rolled up; they are two
palms three
digits long, and their inside diameter is three and a half
digits; into
these two pipes the nozzles of the bellows penetrate a distance of
three digits from their valves. The lid of the dome consists of an iron band
at the bottom, two digits
wide, and of three curved iron bars, which extend
from one point on the
band to the point opposite; they cross each other at
the top, where
they are fixed by means of iron rivets. On the under side of
the bars there are likewise plates fastened by
rivets; each of the plates has
small holes the size of a finger, so
that the lute will adhere when the interior
is lined. The dome has three iron rings engaged in wide holes in the heads of
iron
claves, which fasten the bars to the middle band at these points. Into
these rings are fastened the hooks of the chains with which the
dome is
raised, when the master is preparing the crucible.
On the sole and the copper plates and the rock of the furnace, lute mixed
with straw is placed to a depth of three digits, and it is pounded with
a wooden
rammer until it is compressed to a depth of one digit only. The rammer-head
is round and three palms high, two palms wide at the
bottom, and tapering
upward; its handle is three feet long, and where
it is set into the rammer
head it is bound around with an iron
band. The top of the stonework in
which the dome rests is also covered with
lute, likewise mixed with straw,
to the thickness of a palm. All this, as soon as it becomes loosened, must
be repaired.
The artificer who undertakes the work of parting the metals, distributes
the operation into two shifts of two days. On the one morning he sprinkles
a little ash into the lute, and when he
has poured some water over it he brushes
it over with a broom. Then he throws in sifted ashes and dampens them
with water, so that they
could be moulded into balls like snow. The ashes
are those from which lye has been made by letting water
percolate
through them, for other ashes which are fatty would have to
be burnt
again in order to make them less fat. When he has made the ashes
smooth by pressing them with his hands, he
makes the crucible slope down
toward the middle; then he tamps it, as I
have described, with a rammer. He afterward, with two small wooden rammers, one held in each hand,
forms the channel through which the litharge flows out. The heads of these
small rammers are each a palm wide, two digits thick,
and one foot high;
the handle of each is somewhat rounded, is a digit
and a half less in
A—AN ARTIFICER TAMPING THE CRUCIBLE WITH A RAMMER. B—LARGE
RAMMER.
C—BROOM. D—TWO SMALLER RAMMERS. E—CURVED IRON
PLATES. F—PART OF
A WOODEN STRIP. G—SIEVE. H—ASHES.
I—IRON SHOVEL. K—IRON PLATE.
L—BLOCK OF WOOD.
M—ROCK. N—BASKET MADE OF WOVEN TWIGS. O—HOOKED
BAR.
P—SECOND HOOKED BAR. Q—OLD LINEN RAG. R—BUCKET.
S—DOESKIN.
T—BUNDLES OF STRAW. V—WOOD. X—CAKES
OF LEAD ALLOY. Y—FORK.
Z—ANOTHER WORKMAN COVERS THE OUTSIDE
OF THE FURNACE WITH LUTE WHERE THE
DOME FITS ON IT. AA—BASKET
FULL OF ASHES. BB—LID OF THE DOME. CC—THE
ASSISTANT
STANDING ON THE STEPS POURS CHARCOAL INTO THE CRUCIBLE THROUGH THE
HO
head as well as the handle is made
of one piece of wood. Then with shoes on,
he descends into the crucible and stamps it in every
direction with his feet,
in which manner it is packed and made sloping. Then he again tamps it
with a large rammer, and removing his shoe from
his right foot he draws a circle
around the crucible with it, and cuts
out the circle thus drawn with an iron
plate. This plate is curved at both ends, is three palms long, as many digits
wide, and has wooden handles a palm and two digits long, and two digits
thick; the iron plate is curved back at the top and ends, which
penetrate
into handles. There are some who use in the place of the plate a strip of
wood, like
the rim of a sieve; this is three digits wide, and is cut out at both
ends that it may be held in the hands. Afterward he tamps the channel
through which the litharge discharges. Lest the ashes should fall out, he
blocks up the aperture with a stone
shaped to fit it, against which he places
a board, and lest this fall,
he props it with a stick. Then he pours in
a basketful of ashes and tamps them with the large
rammer; then again and
again he pours in ashes and tamps them with the
rammer. When the
channel has been made, he throws dry ashes all over the
crucible with a sieve,
and smooths and rubs it with his hands. Then he throws three basketsful
of damp ashes on the margin all round
the edge of the crucible, and lets down
the dome. Soon after, climbing upon the crucible, he builds up ashes all
around
it, lest the molten alloy should flow out. Then, having raised the lid of
the dome, he throws a basketful of
charcoal into the crucible, together with
an iron shovelful of glowing
coals, and he also throws some of the latter
through the apertures in
the sides of the dome, and he spreads them with the
same shovel. This work and labour is finished in the space of two hours.
An iron plate is set in the ground under the channel, and upon this is
placed a wooden block, three feet and a palm long, a foot and two palms
and
as many digits wide at the back, and two palms and as many digits
wide in
front; on the block of wood is placed a stone, and over it an
iron plate similar
to the bottom one, and upon this he puts a basketful
of charcoal, and also
an iron shovelful of burning charcoals. The crucible is heated in an
hour, and then, with the hooked bar with
which the litharge is drawn off, he
stirs the remainder of the charcoal
about. This hook is a palm long and three
digits wide, has the form of a double
triangle, and has an iron handle four
feet long, into which is set a
wooden one six feet long. There are some who
use instead a simple hooked bar. After about an hour's time, he stirs the
charcoal again with the bar,
and with the shovel throws into the crucible
the burning charcoals
lying in the channel; then again, after the space of an
hour, he stirs
the burning charcoals with the same bar. If he did not thus
stir them about, some blackness would remain in the
crucible and that part
would be damaged, because it would not be
sufficiently dried. Therefore
the assistant stirs and turns the burning charcoal that it may
be entirely
burnt up, and so that the crucible may be well heated,
which takes three
hours; then the crucible is left quiet for the
remaining two hours.
When the hour of eleven has struck, he sweeps up the charcoal ashes with
a broom and throws them out of the crucible. Then he climbs on to the
dome, and passing his hand in through its
opening, and dipping an old linen
rag in a bucket of water mixed with
ashes, he moistens the whole of the
crucible and sweeps it. In this way he uses two bucketsful of the mixture,
each holding five
Roman
when the metals are being parted, should break open; after this he rubs
the
crucible with a doe skin, and fills in the cracks. Then he places at the left side
of the channel, two fragments of
hearth-lead, laid one on the top of the other,
so that when partly
melted they remain fixed and form an obstacle, that the
litharge will
not be blown about by the wind from the bellows, but remain in
its
place. It is expedient, however, to use a brick in the place of the
hearth
lead, for as this gets much hotter, therefore it causes the
litharge to form
more rapidly. The crucible in its middle part is made two palms and as
many digits
deeper.
There are some who having thus prepared the crucible, smear it over
with
incense
it up in a sponge and then squeezing
it out again; there are others who
smear over it a liquid consisting of
white of egg and double the amount of
bullock's blood or marrow. Some throw lime into the crucible through a
sieve.
Afterward the master of the works weighs the lead with which the gold
or
silver or both are mixed, and he sometimes puts a hundred
into the crucible, but
frequently only sixty, or fifty, or much less. After it
has been weighed, he strews about in the crucible three small
bundles of
straw, lest the lead by its weight should break the surface. Then he places
in the channel several cakes of lead alloy, and through
the aperture at the rear
of the dome he places some along the sides;
then, ascending to the opening at
the top of the dome, he arranges in
the crucible round about the dome the
cakes which his assistant hands
to him, and after ascending again and passing
his hands through the
same aperture, he likewise places other cakes inside the
crucible. On the second day those which remain he, with an iron fork,
places on
the wood through the rear aperture of the dome.
When the cakes have been thus arranged through the hole at the top of
the dome, he throws in charcoal with a basket woven of wooden twigs. Then
he places the lid over the dome, and the assistant covers over the
joints with
lute. The master himself throws half a basketful of charcoal into the crucible
through the aperture next to the nozzle pipe, and prepares the bellows,
in
order to be able to begin the second operation on the morning of the
following
day. It takes the space of one hour to carry out such a piece of work, and
These hours all reckoned up make a sum of eight
hours.
Now it is time that we should come to the second operation.
In the
morning the workman takes up two shovelsful of live charcoals and
throws
them into the crucible through the aperture next to the pipes of
the nozzles;
then through the same hole he lays upon them small pieces
of fir-wood or of
pitch pine, such as are generally used to cook fish. After this the water-gates
are opened, in order that the machine may be
turned which depresses the levers
of the bellows. In the space of one hour the lead alloy is melted; and when this
has
been done, he places four sticks of wood, twelve feet long, through the
hole in the back of the dome, and as many through the channel; these
sticks, lest they should damage the crucible, are both weighted on the
ends
and supported by trestles; these trestles are made of a beam,
three feet
long, two palms and as many digits wide, two palms thick,
and have two
spreading legs at each end. Against the trestle, in front of the channel, there
is placed an iron
plate, lest the litharge, when it is extracted from the furnace,
should
splash the smelter's shoes and injure his feet and legs. With an iron
shovel or a fork he places the remainder of the cakes
through the aperture at
the back of the dome on to the sticks of wood
already mentioned.
The native silver, or silver glance, or grey silver, or ruby silver, or any
other sort, when it has been flattened out
iron crucible, is poured
into the molten lead mixed with silver, in order that
impurities may be
separated. As I have often said, this molten lead mixed
with silver is called
When the long sticks of wood are burned up at the fore end, the
master,
with a hammer, drives into them pointed iron bars, four feet long and
two digits wide at the front end, and beyond that one and a half digits
wide
then rest on the trestles. There are others who, when they separate metals,
put two such sticks of
wood into the crucible through the aperture which is
between the
bellows, as many through the holes at the back, and one through
the
channel; but in this case a larger number of long sticks of wood is
necessary, that is, sixty; in the former case, forty long sticks of
wood suffice
to carry out the operation. When the lead has been heated for two hours,
it is stirred with a hooked
bar, that the heat may be increased.
If it be difficult to separate the lead from the silver, he throws copper
and charcoal dust into the molten silver-lead alloy. If the alloy of argen
tiferous gold and lead, or the silver-lead
alloy, contains impurities from the
ore, then he throws in either equal
portions of argol and Venetian glass or of
sal-ammoniac, or of Venetian
glass and of Venetian soap; or else unequal
portions, that is, two of
argol and one of iron rust; there are some who
mix a little saltpetre
with each compound. To one
alloy is added a
to whether it is more or less impure. The powder certainly separates the
impurities from the alloy. Then, with a kind of rabble he draws out through
A—FURNACE. B—STICKS OF WOOD. C—LITHARGE. D—PLATE.
E—THE FOREMAN
WHEN HUNGRY EATS BUTTER, THAT THE POISON WHICH THE
CRUCIBLE EXHALES MAY NOT
HARM HIM, FOR THIS IS A SPECIAL REMEDY AGAINST
THAT POISON.
the lead makes this scum when it becomes
hot, but that less of it may be
made it must be stirred frequently with
the bar.
Within the space of a quarter of an hour the crucible absorbs the lead;
at the time when it penetrates into the crucible it leaps and bubbles. Then
the master takes out a little lead with an iron ladle, which he
assays, in order
to find what proportion of silver there is in the
whole of the alloy; the
ladle is five digits wide, the iron part of its
handle is three feet long and the
wooden part the same. Afterward, when they are heated, he extracts with
a bar the litharge
which comes from the lead and the copper, if there be any
of it in the
alloy. Wherefore, it might more rightly be called
than of silverThere is no injury to the silver, when the lead and copper
are separated
from it. In truth the lead becomes much purer in the crucible
of the other
furnace, in which silver is refined. In ancient times, as the
author Pliny
crucible, and the litharge flowed down from the upper one into
the lower
one, out of which it was lifted up and rolled round with a
stick in order that
it might be of moderate weight. For which reason, they formerly made it
into small tubes or pipes, but
now, since it is not rolled round a stick, they
make it into bars.
If there be any danger that the alloy might flow out with the litharge, the
foreman keeps on hand a piece of lute, shaped like a cylinder and
pointed at
both ends; fastening this to a hooked bar he opposes it to
the alloy so that
it will not flow out.
Now when the colour begins to show in the silver, bright spots appear,
some of them being almost white, and a moment afterward it becomes
absolutely white. Then the assistant lets down the water-gates, so that, the
race being
closed, the water-wheel ceases to turn and the bellows are still. Then the master pours several buckets of water on to the silver to cool it;
others pour beer over it to make it whiter, but this is of no
importance since
the silver has yet to be refined. Afterward, the cake of silver is raised with
the pointed iron bar, which
is three feet long and two digits wide, and has a
wooden handle four
feet long fixed in its socket. When the cake of silver has
been taken from the crucible, it is laid
upon a stone, and from part of it the
hearth-lead, and from the other
part the litharge, is chipped away with a
hammer; then it is cleansed
with a bundle of brass wire dipped in water. When the lead is separated from the silver, more silver is frequently found
than when it was assayed; for instance, if before there were three
as many
and a halfOften the hearth-lead remaining in the crucible is a palm
deep; it is
taken out with the rest of the ashes and is sifted, and that which
remains in the sieve, since it is hearth-lead, is added to the
hearth-lead
A—CAKE. B—STONE. C—HAMMER. D—BRASS WIRE.
E—BUCKET CONTAINING WATER.
F—FURNACE FROM WHICH THE CAKE
HAS BEEN TAKEN, WHICH IS STILL SMOKING.
G—LABOURER CARRYING A
CAKE OUT OF THE WORKS.
The ashes which pass through the sieve are of the same use as they were
at first, for, indeed, from these and pulverised bones they make the
cupels. Finally, when much of it has accumulated, the yellow
the walls of the
furnace, and likewise to those rings of the dome near the
apertures, is
cleared away.
I must also describe the crane with which the dome is raised.
When
it is made, there is first set up a rectangular upright post twelve
feet
long, each side of which measures a foot in width. Its lower pinion turns
in a bronze socket set in an oak sill; there are
two sills placed crosswise so
fits in the
mortise of the first, thus making a kind of a cross; these sills are
three feet long and one foot wide and thick. The crane-post is round at its
upper end and is cut down to a depth of
three palms, and turns in a band
fastened at each end to a roof-beam,
from which springs the inclined chimney
wall. To the crane-post is affixed a frame, which is made in this way: first, at a
height of a cubit from the bottom, is mortised into the crane-post a
small
cross-beam, a cubit and three digits long, except its tenons, and
two palms in
width and thickness. Then again, at a height of five feet above it, is another
small
cross-beam of equal length, width, and thickness, mortised into the
crane-post. The other ends of these two small cross-beams are mortised
into an
upright timber, six feet three palms long, and three-quarters wide
and
thick; the mortise is transfixed by wooden pegs. Above, at a height of
three palms from the lower small cross-beam, are
two bars, one foot one palm
long, not including the tenons, a palm
three digits wide, and a palm thick,
which are mortised in the other
sides of the crane-post. In the same manner,
under the upper small cross-beam are two bars of the
same size. Also in the
upright timber there are mortised the same number of bars,
of the same length
as the preceding, but three digits thick, a palm two
digits wide, the two
lower ones being above the lower small cross-beam. From the upright
timber near the upper small cross-beam, which at its
other end is mortised
into the crane-post, are two mortised bars. On the outside of this frame,
boards are fixed to the small cross-beams,
but the front and back parts of the
frame have doors, whose hinges are
fastened to the boards which are fixed
to the bars that are mortised to
the sides of the crane-post.
Then boards are laid upon the lower small cross-beam, and at a height
of
two palms above these there is a small square iron axle, the sides of which
are two digits wide; both ends of it are round and turn in bronze or
iron
bearings, one of these bearings being fastened in the crane-post,
the other in
the upright timber. About each end of the small axle is a wooden disc, of three
palms and a
digit radius and one palm thick, covered on the rim with an iron
band;
these two discs are distant two palms and as many digits from each
digits thick and are placed three digits apart. Thus a drum is made, which
is a palm and a digit distant from the
upright timber, but further from the
crane-post, namely, a palm and
three digits. At a height of a foot and a
palm above this little axle is a second
small square iron axle, the thickness of
which is three digits; this
one, like the first one, turns in bronze or iron
bearings. Around it is a toothed wheel, composed of two discs a foot three
palms
in diameter, a palm and two digits thick: on the rim of this there
are
twenty-three teeth, a palm wide and two digits thick; they protrude
a
palm from the wheel and are three digits apart. And around this same
axle, at a distance of two palms and as many digits
toward the upright
timber, is another disc of the same diameter as the
wheel and a palm thick;
this turns in a hollowed-out place in the
upright timber. Between this disc
and the disc of the toothed wheel another drum is
made, having likewise five
rundles. There is, in addition to this second axle, at a height of a cubit
above
it, a small wooden axle, the journals of which are of iron; the ends
are bound round with iron rings so that the journals may remain firmly
fixed,
and the journals, like the little iron axles, turn in bronze or
iron bearings. This third axle is at a distance of about a cubit from the upper small
cross
beam; it has, near the upright timber, a toothed wheel two
and a half feet
in diameter, on the rim of which are twenty-seven
teeth; the other part of
this axle, near the crane-post, is covered
with iron plates, lest it should be worn
away by the chain which winds
around it. The end link of the chain is fixed
in an iron pin driven into the little
axle; this chain passes out of the frame
and turns over a little pulley
set between the beams of the crane-arm.
Above the frame, at a height of a foot and a palm, is the crane-arm.
This
consists of two beams fifteen feet long, three palms wide, and two
thick,
mortised into the crane-post, and they protrude a cubit from the
back of the
crane-post and are fastened together. Moreover, they are fastened by means
of a wooden pin which penetrates
through them and the crane-post; this
pin has at the one end a broad
head, and at the other a hole, through which
is driven an iron bolt, so
that the beams may be tightly bound into the crane
post. The beams of the crane-arm are supported and stayed by means of
two
oblique beams, six feet and two palms long, and likewise two palms wide
and thick; these are mortised into the crane-post at their lower ends,
and
their upper ends are mortised into the beams of the crane-arm at a
point
about four feet from the crane-post, and they are fastened with
iron nails. At the back of the upper end of these oblique beams, toward the crane-post,
is an iron staple, fastened into the lower sides of the beams of the
crane-arm, in
order that it may hold them fast and bind them. The outer end of each
beam of the crane-arm is set in a rectangular iron
plate, and between these
are three rectangular iron plates, fixed in
such a manner that the beams of the
crane-arm can neither move away
from, nor toward, each other. The upper
sides of these crane-arm beams are covered with iron plates
for a length of
six feet, so that a trolley can move on it.
A—CRANE-POST. B—SOCKET. C—OAK CROSS-SILLS. D—BAND.
E—ROOF-BEAM.
F—FRAME. G—LOWER SMALL CROSS-BEAM.
H—UPRIGHT TIMBER. I—BARS WHICH
COME FROM THE SIDES OF THE
CRANE-POST. K—BARS WHICH COME FROM THE SIDES OF
THE UPRIGHT
TIMBER. L—RUNDLE DRUMS. M—TOOTHED WHEELS. N—CHAIN.
O—PULLEY. P—BEAMS OF THE CRANE-ARM. Q—OBLIQUE BEAMS
SUPPORTING THE BEAMS
OF THE CRANE-ARM. R—RECTANGULAR IRON PLATES.
S—TROLLEY. T—DOME OF THE
The body of the trolley is made of wood from the Ostrya or any other
hard tree, and is a cubit long, a foot wide, and three palms thick; on
both
edges of it the lower side is cut out to a height and width of a
palm, so that
the remainder may move backward and forward between the
two beams of
the crane-arm; at the front, in the middle part, it is cut
out to a width of
two palms and as many digits, that a bronze pulley,
around a small iron
axle, may turn in it. Near the corners of the trolley are four holes, in which
as many small
wheels travel on the beams of the crane-arm. Since this
trolley, when it travels backward and forward, gives out a
sound somewhat
similar to the barking of a dog, we have given it this
nameIt is propelled
forward by means of a crank, and is drawn back by means
of a chain. There
is an iron hook whose ring turns round an iron pin fastened to the
right side
of the trolley, which hook is held by a sort of clavis,
which is fixed in the
right beam of the crane-arm.
At the end of the crane-post is a bronze pulley, the iron axle of which is
fastened in the beams of the crane-arm, and over which the chain passes
as it comes from the frame, and then, penetrating through the hollow in
the
top of the trolley, it reaches to the little bronze pulley of the
trolley, and passing
over this it hangs down. A hook on its end engages a ring, in which are
fixed the top links of
three chains, each six feet long, which pass through
the three iron
rings fastened in the holes of the claves which are fixed into
the
middle iron band of the dome, of which I have spoken.
Therefore when the master wishes to lift the dome by means of the
crane,
the assistant fits over the lower small iron axle an iron crank, which
projects from the upright beam a palm and two digits; the end of the
little
axle is rectangular, and one and a half digits wide and one
digit thick; it is
set into a similar rectangular hole in the crank,
which is two digits long and a
little more than a digit wide. The crank is semi-circular, and one foot three
palms and two digits
long, as many digits wide, and one digit thick. Its
handle is straight and round, and three palms long, and one and a
half digits
thick. There is a hole in the end of the little axle, through which an iron
pin
is driven so that the crank may not come off. The crane having four
drums, two of which are rundle-drums and two
toothed-wheels, is more easily
moved than another having two drums, one
of which has rundles and the
other teeth.
Many, however, use only a simple contrivance, the pivots of whose
crane-post turn in the same manner, the one in an iron socket, the
other in a
ring. There is a crane-arm on the crane-post, which is supported by an
oblique
beam; to the head of the crane-arm a strong iron ring is fixed,
which
engages a second iron ring. In this iron ring a strong wooden lever-bar
is fastened firmly, the head
of which is bound by a third iron ring, from which
hangs an iron hook,
which engages the rings at the ends of the chains from
the dome. At the other end of the lever-bar is another chain, which, when
it is
pulled down, raises the opposite end of the bar and thus the dome; and
when it is relaxed the dome is lowered.
A—CHAMBER OF THE FURNACE. B—ITS BED. C—PASSAGES.
D—RAMMER.
E—MALLET. F—ARTIFICER MAKING TUBES FROM
LITHARGE ACCORDING TO THE ROMAN
METHOD. G—CHANNEL.
H—LITHARGE. I—LOWER CRUCIBLE OR HEARTH. K—STICK.
L—TUBES.
In certain places, as at Freiberg in Meissen, the upper part of the
cupellation furnace is vaulted almost like an oven. This chamber is four
feet high and has either two or three apertures, of
which the first, in
front, is one and a half feet high and a foot wide,
and out of this flows
the litharge; the second aperture and likewise
the third, if there be three,
are at the sides, and are a foot and a
half high and two and a half feet wide,
in order that he who prepares
the crucible may be able to creep into the
furnace. Its circular bed is made of cement, it has two passages two feet high
and one foot wide, for letting out the vapour, and these lead directly
through
from one side to the other, so that the one passage crosses the
other at right
angles, and thus four openings are to be seen; these are
covered at the top
by rocks, wide, but only a palm thick. On these and on the other parts
of the interior of the bed made of
cement, is placed lute mixed with straw,
to a depth of three digits, as
it was placed over the sole and the plates of
copper and the rocks of
that other furnace. This, together with the ashes which
are thrown in, the master or the
assistant, who, upon his knees, prepares
the crucible, tamps down with
short wooden rammers and with mallets
likewise made of wood.
A—FURNACE SIMILAR TO AN OVEN. B—PASSAGE C—IRON BARS.
D—HOLE THROUGH
WHICH THE LITHARGE IS DRAWN OUT. E—CRUCIBLE
WHICH LACKS A DOME. F—THICK
STICKS. G—BELLOWS
The cupellation furnace in Poland and Hungary is likewise vaulted at the
top, and is almost similar to an oven, but in the lower part the bed is
solid,
and there is no opening for the vapours, while on one side of
the crucible is a
wall, between which and the bed of the crucible is a
passage in place of the
opening for vapours; this passage is covered by
iron bars or rods extending
from the wall to the crucible, and placed a
distance of two digits from each
other. In the crucible, when it is prepared, they first scatter straw, and then
they lay in it cakes of silver-lead alloy, and on the iron bars they
lay wood,
which when kindled heats the crucible. They melt cakes to the weight of some
times eighty They
stimulate a mild fire by means of a blast from the bellows, and
throw on to the
bars as much wood as is required to make a flame which
will reach into the
crucible, and separate the lead from the silver. The litharge is drawn out
on the other side through an aperture that is
just wide enough for the master
to creep through into the crucible. The Moravians and Carni, who very
rarely make more than a
the lead from it, neither in a furnace resembling an oven, nor in the
crucible
covered by a dome, but on a crucible which is without a cover
and exposed to
the wind; on this crucible they lay cakes of silver-lead
alloy, and over them
they place dry wood, and over these again thick
green wood. The wood
having been kindled, they stimulate the fire by means of a
bellows.
I have explained the method of separating lead from gold or silver.
Now
I will speak of the method of refining silver, for I have already
explained
the process for refining gold. Silver is refined in a refining furnace,
over whose hearth is an arched
chamber built of bricks; this chamber
in the front part is three feet
high. The hearth itself is five feet long
an four wide. The walls are unbroken along the sides and back, but
in front one
chamber is placed over the other, and above these and the
wall is the
upright chimney. The hearth has a round pit, a cubit wide and two
palms deep, into which
are thrown sifted ashes, and in this is placed a prepared
earthenware
“test,” in such a manner that it is surrounded on all sides
by ashes to a height equal to its own. The earthenware test is filled
with a powder consisting of equal
portions of bones ground to powder, and of
ashes taken from the
crucible in which lead is separated from gold or silver;
others mix
crushed brick with the ashes, for by this method the powder
attracts no
silver to itself. When the powder has been made up and
moistened with water, a little is
thrown into the earthenware test and tamped
with a wooden pestle. This pestle is round, a foot long, and a palm and a
digit wide, out of
which extend six teeth, each a digit thick, and a digit and a
third
long and wide, and almost a digit apart; these six teeth form a circle,
and in the centre of them is the seventh tooth, which is round and of
the
same length as the others, but a digit and a half thick; this
pestle tapers a
little from the bottom up, that the upper part of the
handle may be round
and three digits thick. Some use a round pestle without teeth.
Then a
A—PESTLE WITH TEETH. B—PESTLE WITHOUT TEETH. C—DISH OR TRAY
FULL OF ASHES.
D—PREPARED TESTS PLACED ON BOARDS OR SHELVES.
E—EMPTY TESTS. F—WOOD.
G—SAW.
little powder is
again moistened, and thrown into the test, and tamped; this
work is
repeated until the test is entirely full of the powder, which the
master then cuts out with a knife, sharp on both sides, and turned
upward at
both ends so that the central part is a palm and a digit
long; therefore it is
partly straight and partly curved. The blade is one and a half digits wide,
and at each end it turns upward
two palms, which ends to the depth of a
palm are either not sharpened
or they are enclosed in wooden handles. The
master holds the knife with one hand and cuts out the powder from
the test,
so that it is left three digits thick all round; then he
sifts the powder of dried
bones over it through a sieve, the bottom of
which is made of closely-woven
bristles. Afterward a ball made of very hard wood, six digits in diameter,
is
placed in the test and rolled about with both hands, in order to make the
inside even and smooth; for that matter he may move the ball about with
only
one hand. The tests
A—STRAIGHT KNIFE HAVING WOODEN HANDLES. B—CURVED KNIFE LIKEWISE
HAVING
WOODEN HANDLES. C—CURVED KNIFE WITHOUT WOODEN HANDLES.
D—SIEVE.
E—BALLS. F—IRON DOOR WHICH THE MASTER LETS
DOWN WHEN HE REFINES SILVER, LEST
THE HEAT OF THE FIRE SHOULD INJURE
HIS EYES. G—IRON IMPLEMENT ON WHICH THE
WOOD IS PLACED WHEN THE
LIQUID SILVER IS TO BE REFINED. H—ITS OTHER PART
PASSING THROUGH
THE RING OF ANOTHER IRON IMPLEMENT ENCLOSED IN THE WALL OF THE
FURNACE.
I—TESTS IN WHICH BURNING CHARCOAL HAS BEEN THROWN.
hold much less
than fifteen
forty, and others fifty. All these tests thus prepared are dried in the sun, or
set in a warm and
covered place; the more dry and old they are the better. All of them, when used for refining silver, are heated by means of burning
charcoal placed in them. Others use instead of these tests an iron ring; but
the test is more
useful, for if the powder deteriorates the silver remains in
it, while
there being no bottom to the ring, it falls out; besides, it is easier to
place in the hearth the test than the iron ring, and furthermore it
requires
much less powder. In order that the test should not break and damage the
silver, some bind
it round with an iron band.
In order that they may be more easily broken, the silver cakes are placed
upon an iron grate by the refiner, and are heated by burning charcoal
placed under them. He has a brass block two palms and two digits long and
wide, with a
channel in the middle, which he places upon a block of hard
wood. Then with a double-headed hammer, he beats the hot cakes of silver
The head of this
hammer is a foot and two digits long, and a palm wide. Others use for this
purpose merely a block of wood channelled in the
top. While the fragments
of the cake are still hot, he seizes them with the
tongs and throws them into
a bowl with holes in the bottom, and pours
water over them. When the
fragments are cooled, he puts them nicely into the test by
placing them so
that they stand upright and project from the test to a
height of two palms, and
lest one should fall against the other, he
places little pieces of charcoal between
them; then he places live
charcoal in the test, and soon two twig basketsful
of charcoal. Then he blows in air with the bellows.
This bellows is double,
and four feet two palms long, and two feet and
as many palms wide at the
back; the other parts are similar to those
described in Book VII. The
nozzle of the bellows is placed in a bronze pipe a foot long, the
aperture in
this pipe being a digit in diameter in front and quite
round, and at the back
two palms wide. The master, because he needs for the operation of refining
A—GRATE. B—BRASS BLOCK. C—BLOCK OF WOOD. D—CAKES OF
SILVER. E—HAMMER.
F—BLOCK OF WOOD CHANNELLED IN THE MIDDLE.
G—BOWL FULL OF HOLES.
H—BLOCK OF WOOD FASTENED TO AN IRON
IMPLEMENT. I—FIR-WOOD. K—IRON BAR.
L—IMPLEMENT WITH A
HOLLOW END. THE IMPLEMENT WHICH HAS A CIRCULAR END IS
SHOWN IN THE NEXT
PICTURE. M—IMPLEMENT, THE EXTREMITY OF WHICH IS BENT
UPWARDS.
N—IMPLEMENT IN THE SHAPE OF TONGS.
bellows
very much inclined, in order that, when the silver has melted, it
may
blow into the centre of the test. When the silver bubbles, he presses the
nozzle down by means of a small
block of wood moistened with water and
fastened to an iron rod, the
outer end of which bends upward. The silver
melts when it has been heated in the test for about an hour;
when it is
melted, he removes the live coals from the test and places
over it two billets
of fir-wood, a foot and three palms long, a palm
two digits wide, one palm
thick at the upper part, and three digits at
the lower. He joins them
together at the lower edges, and into the billets he again
throws the coals,
for a fierce fire is always necessary in refining
silver. It is refined in two or
three hours, according to whether it was pure or
impure, and if it is impure it
is made purer by dropping granulated
copper or lead into the test at the
same time. In order that the refiner may sustain the great heat from the fire
while
the silver is being refined, he lets down an iron door, which is three feet
long and a foot and three palms high; this door is held on both ends in
iron
plates, and when the operation is concluded, he raises it again
with an iron
shovel, so that its edge holds against the iron hook in
the arch, and thus the
door is held open. When the silver is nearly refined, which may be judged
by the space of
time, he dips into it an iron bar, three and a half feet
long and a
digit thick, having a round steel point. The small drops of silver
that adhere to the bar he places on the brass
block and flattens with
a hammer, and from their colour he decides
whether the silver is sufficiently
refined or not. If it is thoroughly purified it is very white, and in a
is only a Some ladle up the silver with a hollow iron
implement. Of each
when very impure, three
The refiner governs the fire and stirs the molten silver with an iron
implement, nine feet long, a digit thick, and at the end first curved
toward
the right, then curved back in order to form a circle, the
interior of which is a
palm in diameter; others use an iron implement,
the end of which is bent
directly upward. Another iron implement has the shape of tongs, with
which, by
compressing it with his hands, he seizes the coals and puts them on
or
takes them off; this is two feet long, one and a half digits wide, and the
third of a digit thick.
When the silver is seen to be thoroughly refined, the artificer removes
the coals from the test with a shovel. Soon afterward he draws water in
a copper ladle, which has a wooden
handle four feet long; it has a small
hole at a point half-way between
the middle of the bowl and the edge, through
which a hemp seed just
passes. He fills this ladle three times with water,
and three times it all flows
out through the hole on to the silver, and slowly
quenches it; if he
suddenly poured much water on it, it would burst asunder
and injure
those standing near. The artificer has a pointed iron bar, three
A—IMPLEMENT WITH A RING. B—LADLE. C—ITS HOLE.
D—POINTED BAR. E—FORKS.
F—CAKE OF SILVER LAID UPON
THE IMPLEMENT SHAPED LIKE TONGS. G—TUB OF WATER.
H—BLOCK OF
WOOD, WITH A CAKE LAID UPON IT. I—HAMMER. K—SILVER AGAIN
PLACED UPON THE IMPLEMENT RESEMBLING TONGS. L—ANOTHER TUB FULL OF
WATER.
M—BRASS WIRES. N—TRIPOD. O—ANOTHER BLOCK.
P—CHISEL. Q—CRUCIBLE OF
THE FURNACE. R—TEST STILL
SMOKING.
feet long, which has a wooden handle as many feet long, and he
puts the end of
this bar into the test in order to stir it. He also stirs it with a hooked iron
bar, of which the hook is two digits
wide and a palm deep, and the iron part
of its handle is three feet
long and the wooden part the same. Then he
removes the test from the hearth with a shovel or a fork, and
turns it over,
and by this means the silver falls to the ground in the
shape of half a sphere;
then lifting the cake with a shovel he throws
it into a tub of water, where
it gives out a great sound. Or else, having lifted the cake of silver with a
fork, he lays it upon
the iron implement similar to tongs, which are placed
across a tub full
of water; afterward, when cooled, he takes it from the
tub again and
lays it on the block made of hard wood and beats it with a
hammer, in
order to break off any of the powder from the test which
adheres to it. The cake is then placed on the implement similar to
tongs, laid over the
tub full of water, and cleaned with a bundle of brass wire
until it is all clean. Afterward he places it on an iron grate or tripod; the
tripod is a palm
and two digits high, one and a half digits wide, and its span
is two
palms wide; then he puts burning charcoal under the tripod or grate,
in
order again to dry the silver that was moistened by the water. Finally,
the Royal Inspector
lays the silver
on a block of wood, and with an engraver's chisel he cuts out two
A—MUFFLE. B—ITS LITTLE WINDOWS. C—ITS LITTLE BRIDGE.
D—BRICKS. E—IRON
DOOR. F—ITS LITTLE WINDOW.
G—BELLOWS. H—HAMMER-CHISEL. I—IRON RING
WHICH SOME
USE INSTEAD OF THE TEST. K—PESTLE WITH WHICH THE ASHES PLACED IN
THE RING ARE POUNDED.
small pieces, one from the under and the
other from the upper side. These
are tested by fire, in order to ascertain whether the silver is
thoroughly refined
or not, and at what price it should be sold to the
merchants. Finally he
impresses upon it the seal of the King or the Prince or the
owner, and, near
the same, the amount of the weight.
There are some who refine silver in tests placed under iron or
earthen
ware muffles. They use a furnace, on the hearth of which they place the test
containing the fragments of silver, and they place the muffle over it;
the In order
to melt the silver, at the sides of the muffle are laid bricks,
upon which the
charcoal is placed, and burning firebrands are put on
the bridge. The
furnace has an iron door, which is covered on the side next to the
fire with lute
in order that it may not be injured. When the door is closed it retains the
heat of the fire, but it has a
small window, so that the artificers may look
into the test and may at
times stimulate the fire with the bellows. Although
by this method silver is refined more slowly than by the other,
nevertheless it is
more useful, because less loss is caused, for a
gentle fire consumes fewer particles
than a fierce fire continually
excited by the blast of the bellows. If, on
account of its great size, the cake of silver can be carried only
with difficulty
when it is taken out of the muffle, they cut it up into
two or three
pieces while it is still hot, with a wedge or a
hammer-chisel; for if they cut
it up after it has cooled, little pieces
of it frequently fly off and are lost.
END OF BOOK X.
Different methods of parting gold from silver,
and, on the other hand,
silver from gold, were dis
cussed in the last book; also the
separation of copper
from the latter, and further, of lead from gold as
well as from silver; and, lastly, the methods for
refining the two
precious metals. Now I will speak
of the methods by which silver must be separated
from copper, and likewise from iron.
The
purposes and use of those who separate silver from
copper, is constructed
in this manner. First, four long walls are built, of which the first, which
is parallel
with the bank of a stream, and the second, are both two hundred and
sixty-four feet long. The second, however, stops at one hundred and fifty-one
feet, and after,
as it were, a break for a length of twenty-four feet, it continues
again until it is of a length equal to the first wall. The third wall is one
hundred and twenty feet long, starting at a point
opposite the sixty-seventh
foot of the other walls, and reaching to
their one hundred and eighty-sixth foot. The height of each of
these walls, and likewise of the other two and of
the transverse walls, of
which I will speak later on, is ten feet, and
the thickness two feet and as
many palms. The second long wall only is built fifteen feet high, because
of the
furnaces which must be built against it. The first long wall is distant
fifteen feet from the second, and the
third is distant the same number of feet
from the fourth, but the
second is distant thirty-nine feet from the third. Then transverse walls are built, the first of which leads from the beginning
of the first long wall to the beginning of the second long wall; and
the second
transverse wall from the beginning of the second long wall
to the beginning of
the fourth long wall, for the third long wall does
not reach so far. Then from
the beginning of the third long wall are built two
walls—the one to the
sixty-seventh foot of the second long wall,
the other to the same point in
the fourth long wall. The fifth transverse wall is built at a distance of ten
feet from the
fourth transverse wall toward the second transverse wall;
SIX LONG WALLS: A—THE FIRST. B—THE FIRST PART OF THE SECOND.
C—THE
FURTHER PART OF THE SECOND. D—THE THIRD. E—THE
FOURTH. F—THE FIFTH.
G—THE SIXTH. FOURTEEN TRANSVERSE
WALLS: H—THE FIRST. I—THE SECOND.
K—THE THIRD.
L—THE FOURTH. M—THE FIFTH. N—THE SIXTH. O—THE
SEVENTH.
P—THE EIGHTH. O—THE NINTH. R—THE TENTH.
S—THE ELEVENTH. T—THE The sixth
transverse wall is built also from the fourth long wall, at a
point distant
thirty feet from the fourth transverse wall, and it
extends as far as the back
of the third long wall. The seventh transverse wall is constructed from
the second long wall,
where this first leaves off, to the third long wall; and
from the back
of the third long wall the eighth transverse wall is built,
extending
to the end of the fourth long wall. Then the fifth long wall is built
from the seventh transverse wall,
starting at a point nineteen feet from the
second long wall; it is one
hundred and nine feet in length; and at a point
twenty-four feet along
it, the ninth transverse wall is carried to the third end
of the second
long wall, where that begins again. The tenth transverse wall is
built from the end of the fifth long wall,
and leads to the further end of the
second long wall; and from there
the eleventh transverse wall leads to the
further end of the first long
wall. Behind the fifth long wall, and five feet
toward the third long wall,
the sixth long wall is built, leading from the
seventh transverse wall;
its length is thirty-five feet, and from its further
end the twelfth
transverse wall is built to the third long wall, and from it the
thirteenth transverse wall is built to the fifth long wall. The fourteenth
transverse wall divides into equal parts the space which
lies between the
seventh transverse wall and the twelfth.
The length, height, breadth, and position of the walls are as above.
Their archways, doors, and openings are made at the same time that the walls
are built. The size of these and the way they are made will be much better
understood hereafter. I will now speak of the furnace hoods and of the roofs.
The first side
every respect to those whose
structure I explained in Book IX, when I
described the works in whose
furnaces are smelted the ores of gold, silver,
and copper. From this side of the hood a roof, which consists of burnt tiles,
extends to the first long wall; and this part of the building contains
the
bellows, the machinery for compressing them, and the instruments
for
inflating them. In the middle space, which is situated between the second
and third
transverse walls, an upright post eight feet high and two feet thick
the second long wall. On that upright post, and in the second transverse
wall, which has at
that point a square hole two feet high and wide, is placed
a beam
thirty-four feet and a palm long. Another beam, of the same length,
width, and thickness, is fixed on the
same upright post and in the third
transverse wall. The heads of those two beams, where they meet, are joined
together with
iron staples. In a similar manner another post is erected, at a
distance of ten feet
from the first upright post in the direction of the fourth
wall, and
two beams are laid upon it and into the same walls in a similar
way to
those I have just now described. On these two beams and on the
fourth long wall are fixed seventeen
cross-beams, forty-three feet and three
palms long, a foot wide, and
three palms thick; the first of these is laid upon
the second
transverse wall, the last lies along the third and fourth transverse
walls; the rest are set in the space between them. These cross-beams are
three feet apart one from the other.
In the ends of these cross-beams, facing the second long wall, are mortised
the ends of the same number of rafters reaching to those timbers which
stand upright on the second long wall, and in this manner is made the
inclined
side of the hood in a similar way to the one described in Book
IX. To prevent
this from falling toward the vertical wall of the hood, there
are iron rods
securing it, but only a few, because the four brick
chimneys which have
to be built in that space partly support it. Twelve feet back are likewise
mortised into the cross-beams, which lie
upon the two longitudinal beams
and the fourth long wall, the lower
ends of as many rafters, whose upper ends
are mortised into the upper
ends of an equal number of similar rafters, whose
lower ends are
mortised to the ends of the beams at the fourth long wall. From the first set of rafters
feet, in order that a
gutter may be well placed in the middle space. Between
these two are again erected two sets of rafters, the lower ends
of which are like
wise mortised into the beams, which lie on the
two longitudinal beams and the
fourth long wall, and are interdistant a
cubit. The upper ends of the ones
fifteen feet long rest on the backs of the
rafters of the first set; the ends of the
others, which are eighteen
feet long, rest on the backs of the rafters of the
second set, which
are longer; in this manner, in the middle of the rafters, is
a
sub-structure. Upon each alternate cross-beam which is placed upon the
two longitudinal
beams and the fourth long wall is erected an upright post,
and that it
may be sufficiently firm it is strengthened by means of a slanting
timber. Upon these posts is laid a long beam, upon which rests one set of
middle
rafters. In a similar manner the other set of middle rafters rests on a
long beam
which is placed upon other posts. Besides this, two feet above
every cross-beam, which is placed on the
two longitudinal beams and the
middle rafters to
the second set of middle rafters; upon the tie-beams is
placed a gutter
hollowed out from a tree. Then from the back of each of
the first set of middle rafters a beam six
feet long reaches almost to the gutter;
to the lower end of this beam
is attached a piece of wood two feet long;
this is repeated with each
rafter of the first set of middle rafters. Similarly
from the back of each rafter of the second set of middle
rafters a little beam,
seven feet long, reaches almost to the gutter;
to the lower end of it
is likewise attached a short piece of wood; this
is repeated on each rafter
of the second set of middle rafters. Then in the upper part, to the first and
second sets of principal
rafters are fastened long boards, upon which are
fixed the burnt tiles;
and in the same manner, in the middle part, they are
fastened to the
first and second sets of middle rafters, and at the lower part to
the
little beams which reach from each rafter of the first and second set of
middle rafters almost to the gutter; and, finally, to the little boards
fastened
to the short pieces of wood are fixed shingles of pinewood
extending into the
gutter, so that the violent rain or melted snow may
not penetrate into the
building. The substructures in the interior which support the second set of
rafters, and those on the opposite side which support the third, being
not
unusual, I need not explain.
In that part of the building against the second long wall are the
furnaces, in which exhausted liquation cakes which have already been
“dried” are smelted, that they may recover once again the
appearance
and colour of copper, inasmuch as they really are copper. The remainder
of the room is occupied by the passage which leads from
the door to the
furnaces, together with two other furnaces, in one of
which the whole cakes
of copper are heated, and in the other the
exhausted liquation cakes are
“dried” by the heat of the
fire.
Likewise, in the room between the third and seventh
two posts are erected
on rock foundation; both of them are eight feet high
and two feet wide
and thick. The one is at a distance of thirteen feet from
the second long wall; the
other at the same distance from the third long wall;
there is a
distance of thirteen feet between them. Upon these two posts and
upon the third transverse wall are laid two
longitudinal beams, forty-one feet
and one palm long, and two feet wide
and thick. Two other beams of the
same length, width, and thickness are laid upon
the upright posts and upon
the seventh transverse wall, and the heads
of the two long beams, where they
meet, are joined with iron staples. On these longitudinal beams are again
placed twenty-one transverse
beams, thirteen feet long, a foot wide, and three
palms thick, of which
the first is set on the third transverse wall, and the last
on the
seventh transverse wall; the rest are laid in the space between these
two, and they are distant from one another three feet. Into the ends of
the transverse beams which face the second long wall,
are mortised the
ends of the same number of rafters erected toward the
upright posts
which are placed upon the second long wall, and in this
manner is made Into the ends of the transverse
beams facing the third long wall, are
mortised the ends of the same
number of rafters rising toward the
rafters of the first inclined side of
the second hood, and in this
manner is made the other inclined side of
the second hood. But to prevent this from falling in upon the opposite
inclined side of
the hood, and that again upon the opposite vertical one,
there are many
iron rods reaching from some of the rafters to those
opposite them; and
this is also prevented in part by means of a few tie-beams,
extending
from the back of the rafters to the back of those which are behind
them. These tie-beams are two palms thick and wide, and have holes made
through them at each end; each of the rafters is bound round with iron
bands three digits wide and half a digit thick, which hold together the
ends
of the tie-beams of which I have spoken; and so that the joints
may be firm,
an iron nail, passing through the plate on both sides, is
driven through the
holes in the ends of the beams. Since one weight counter-balances another, the
rafters on the opposite
hoods cannot fall. The tie-beams and middle posts
which have to support the gutters and the
roof, are made in every particular
as I stated above, except only that
the second set of middle rafters are not
longer than the first set of
middle rafters, and that the little beams which
reach from the back of
each rafter of the second set of middle rafters nearly
to the gutter
are not longer than the little beams which reach from the back
of each
rafter of the first set of middle rafters almost to the gutter. In this
part of the building, against the second long wall, are the
furnaces in which
copper is alloyed with lead, and in which
“slags” are re-smelted. Against
the third long wall are the furnaces in which silver and lead
are liquated from
copper. The interior is also occupied by two cranes, of which one deposits
on
the ground the cakes of copper lifted out of the moulding pans; the other
lifts them from the ground into the second furnace.
On the third and the fourth long walls are set twenty-one beams eighteen
feet and three palms long. In mortises in them, two feet behind the third long
wall, are set the
ends of the same number of rafters erected opposite to the
rafters of
the other inclined wall of the second furnace hood, and in this
manner
is made the third inclined wall, exactly similar to the others. The
ends of as many rafters are mortised into these beams where they are
fixed in
the fourth long wall; these rafters are erected obliquely, and
rest against the
backs of the preceding ones and support the roof,
which consists entirely of
burnt tiles and has the usual substructures. In this part of the building
there are two rooms, in the first of which
the cakes of copper, and in the other
the cakes of lead, are
stored.
In the space enclosed between the ninth and tenth transverse walls and
the second and fifth long walls, a post twelve feet high and two feet
wide and
thick is erected on a rock foundation; it is distant thirteen
feet from the
second long wall, and six from the fifth long wall. Upon this post and upon
the ninth transverse wall is laid a beam
thirty-three feet and three palms
long, and two palms wide and thick. Another beam, also of the same length,
width and thickness, is laid upon
the same post and upon the tenth transverse
of iron
staples. On these beams and on the fifth long wall are placed ten
cross-beams,
eight feet and three palms long, the first of which is placed on
the
ninth transverse wall, the last on the tenth, the remainder in the space
between them; they are distant from one another three feet. Into the
ends of the cross-beams facing the second long wall, are
mortised the ends of
the same number of rafters inclined toward the
posts which stand vertically
upon the second long wall. This, again, is the manner in which the inclined
side of the furnace
hood is made, just as with the others; at the top
where the fumes are
emitted it is two feet distant from the vertical side. The ends of the same number of rafters are mortised into the cross-beams,
where they are set in the fifth long wall; each of them is set up
obliquely and
rests against the back of one of the preceding set; they
support the roof,
made of burnt tiles. In this part of the building, against the second long
wall, are four
furnaces in which lead is separated from silver, together with
the
cranes by means of which the domes are lifted from the crucibles.
In that part of the building which lies between the first long wall and
the break in the second long wall, is the stamp with which the copper
cakes
are crushed, and the four stamps with which the accretions that
are chipped
off the walls of the furnace are broken up and crushed to
powder, and likewise
the bricks on which the exhausted liquation cakes
of copper are stood to
be “dried.” This room has the usual
roof, as also has the space between
the seventh transverse wall and the
twelfth and thirteenth transverse walls.
At the sides of these rooms are the fifth, the sixth, and the third long
walls. This part of the building is divided into two parts, in the first of
which stand the little furnaces in which the artificer assays metals;
and the
bone ash, together with the other powders, are kept here. In the other room
is prepared the powder from which the hearths and the
crucibles of the fur
naces are made. Outside the building, at the back of the fourth long wall,
near the door
to the left as you enter, is a hearth in which smaller
masses of lead
are melted from large ones, that they may be the more easily
weighed;
because the masses of lead, just as much as the cakes of copper,
ought
to be first prepared so that they can be weighed, and a definite weight
can be melted and alloyed in the furnaces. To begin with, the hearth in
which the masses of lead are liquefied is
six feet long and five wide; it is
protected on both sides by rocks
partly sunk into the earth, but a palm higher
than the hearth, and it
is lined in the inside with lute. It slopes toward the
middle and toward the front, in order that the
molten lead may run down
and flow out into the dipping-pot. There is a wall at the back of the hearth
which protects the fourth long
wall from damage by the heat; this wall,
which is made of bricks and
lute, is four feet high, three palms thick, and five
feet long at the
bottom, and at the top three feet and two palms long; there
fore it
narrows gradually, and in the upper part are laid seven bricks, the
middle ones of which are set upright, and the end ones inclined; they
are all
thickly coated with lute. In front of the hearth is a dipping-pot, whose pit is
a foot deep, and a
foot and three palms wide at the top, and gradually narrows.
A—HEARTH. B—ROCKS SUNK INTO THE GROUND. C—WALLS WHICH
PROTECT THE
FOURTH LONG WALL FROM DAMAGE BY FIRE. D—DIPPING-POT.
E—MASSES OF LEAD.
F—TROLLEY. G—ITS WHEELS.
H—CRANE. I—TONGS. K—WOOD. L—MOULDS.
M—LADLE. N—PICK. O—CAKES.
in
the hearth so that one end of each billet faces the wall, and the other end
the dipping-pot. Then, assisted by other workmen, he pushes the mass
of lead forward with
crowbars on to a low trolley, and draws it to the
crane. The trolley consists of planks fastened together, is two and one-half
feet wide and five feet long, and has two small iron axles, around
which at
each end revolve small iron wheels, two palms in diameter and
as many digits
wide. The trolley has a tongue, and attached to this is a rope, by which it is
drawn to the crane. The crane is exactly similar to those in the second part
of the works,
except that the crane-arm is not so long. The tongs in whose
jaws
both of the jaws, when struck with a hammer, impinge upon the mass and
are
driven into it. The upper part of both handles of the tongs are curved back,
the one to
the right, the other to the left, and each handle is engaged in one
of
the lowest links of two short chains, which are three links long. The upper
links are engaged in a large round ring, in which is fixed the
hook of a chain
let down from the pulley of the crane-arm. When the crank of the crane
is turned, the mass is lifted and is carried
by the crane-arm to the hearth and
placed on the wood. The workmen wheel up one mass after another and
place them in a similar
manner on the wood of the hearth; masses which
weigh a total of about a
hundred and sixty
upon the wood and melted at one time. Then a workman throws charcoal
on the masses, and all are made ready in
the evening. If he fears that it may
rain, he covers it up with a cover, which may be
moved here and there; at the
back this cover has two legs, so that the
rain which it collects may flow down
the slope on to the open ground. Early in the morning of the following day,
he throws live coals on the
charcoal with a shovel, and by this method the
masses of lead melt, and
from time to time charcoal is added. The lead, as
soon as it begins to run into the dipping-pot, is ladled
out with an iron ladle
into copper moulds such as the refiners
generally use. If it does not cool
immediately he pours water over it, and then sticks
the pointed pick into
it and pulls it out. The pointed end of the pick is three palms long and
the round end is two
digits long. It is necessary to smear the moulds with a
wash of lute, in order that,
when they have been turned upside down and
struck with the broad round
end of the pick, the cakes of lead may fall out
easily. If the moulds are not washed over with the lute, there is a risk that
they may be melted by the lead and let it through. Others take hold of a
billet of wood with their left hand, and with the
heavy lower end of it they
pound the mould, and with the right hand
they stick the point of the pick
into the cake of lead, and thus pull
it out. Then immediately the workman
pours other lead into the empty moulds, and
this he does until the work of
melting the lead is finished. When the lead is melted, something similar to
litharge is produced; but
it is no wonder that it should be possible to make
alone when melted by a fierce fire in the cupellation furnace.
these cakes of lead
are carried into the lead store-room.
The cakes of copper, put into wheelbarrows, are carried into the third
part of the building, where each is laid upon a saddle, and is broken
up by
the impact of successive blows from the iron-shod stamp. This machine
is made by placing upon the ground a block of oak, five
feet long and three feet
A—BLOCK OF WOOD. B—UPRIGHT POSTS. C—TRANSVERSE BEAMS.
D—HEAD OF THE
STAMP. E—ITS TOOTH. F—THE HOLE IN THE
STAMP-STEM. G—IRON BAR. H—MASSES
OF LEAD. I—THE
BRONZE SADDLE. K—AXLE. L—ITS ARMS. M—LITTLE IRON AXLE.
N—BRONZE PIPE.
wide and thick; it is cut out in the middle
for a length of two feet and two
palms, a width of two feet, and a
depth of three palms and two digits, and is
open in front; the higher
part of it is at the back, and the wide part lies flat
in the block. In the middle of it is placed a bronze saddle.
Its base
is a palm and two digits wide, and is planted between two
masses of
lead, and extends under them to a depth of a palm on both
sides. The whole saddle is three palms and two digits wide, a foot long, and
Upon each end of the block stands a post, a cubit wide
and thick, the
upper end of which is somewhat cut away and is mortised into
the beams
of the building. At a height of four feet and two digits above the
block there are joined
to the posts two transverse beams, each of which is
three palms wide
and thick; their ends are mortised into the upright posts,
and holes
are bored through them; in the holes are driven iron claves,
horned in
front and so driven into the post that one of the horns of each
points
upward and the other downward; the other end of each clavis is
perforated, and a wide iron wedge is inserted and driven into the
holes, and
thus holds the transverse beams in place. These transverse beams have in the
middle a square opening three palms
and half a digit wide in each
direction, through which the iron-shod
stamp passes. At a height of three
feet and two palms above these transverse beams
there are again two beams
of the same kind, having also a square
opening and holding the same stamp. This stamp is square, eleven feet long, three palms wide and thick; its iron
shoe is a foot and a palm long; its head is two palms long and wide, a
palm
two digits thick at the top, and at the bottom the same number of
digits, for
it gradually narrows. But the tail is three palms long; where the head
begins is two palms
wide and thick, and the further it departs from the same
the narrower
it becomes. The upper part is enclosed in the stamp-stem, and
it is perforated so
that an iron bolt may be driven into it; it is bound by three
rectangular iron bands, the lowest of which, a palm wide, is between
the iron
shoe and the head of the stamp; the middle band, three digits
wide, follows
next and binds round the head of the stamp, and two
digits above is the
upper one, which is the same number of digits wide. At a distance of two
feet and as many digits above the lowest part of
the iron shoe, is a rectangular
tooth, projecting from the stamp for a
distance of a foot and a palm; it is
two palms thick, and when it has
extended to a distance of six digits from the
stamp it is made two
digits narrower. At a height of three palms upward
from the tooth there is a round hole
in the middle of the stamp-stem, into
which can be thrust a round iron
bar two feet long and a digit and a half in
diameter; in its hollow end
is fixed a wooden handle two palms and the same
number of digits long. The bar rests on the lower transverse beam, and holds
up the stamp when
it is not in use. The axle which raises the stamp
has on each side two arms, which are two
palms and three digits distant
from each other, and which project from
the axle a foot, a palm and two
digits; penetrating through them are
bolts, driven in firmly; the arms are
each a palm and two digits wide
and thick, and their round heads, for a foot
downward on either side,
are covered with iron plates of the same width as
the arms and fastened
by iron nails. The head of each arm has a round
hole, into which is inserted an iron
pin, passing through a bronze pipe; this
little axle has at the one end
a wide head, and at the other end a perforation
through which is driven
an iron nail, lest this little axle should fall out of the
arms. The bronze pipe is two palms long and one in diameter; the little
iron
axle penetrates through its round interior, which is two digits in diameter.
The bronze pipe not only revolves round the little iron axle, but it also
the bronze tube in their turn raise the tooth and the
stamp. When the
little iron axle and the bronze pipe have been taken out of the
arms, the tooth
of the stamps is not raised, and other stamps may be
raised without this one. Further on, a drum with spindles fixed around the axle of a water-wheel
moves the axle of a toothed drum, which depresses the sweeps of the
bellows
in the adjacent fourth part of the building; but it turns in
the contrary
direction; for the axis of the drum which raises the
stamps turns toward
the north, while that one which depresses the
sweeps of the bellows turns
toward the south.
Those cakes which are too thick to be rapidly broken by blows from
the
iron-shod stamp, such as are generally those which have settled in the
bottom of the crucible,They
are there heated in a furnace, which is twenty-eight feet distant
from the
second long wall and twelve feet from the second transverse
wall. The three
sides of this furnace are built of rectangular rocks, upon
which bricks are laid;
the back furnace wall is three feet and a palm
high, and the rear of the side
walls is the same; the side walls are
sloping, and where the furnace is open in
front they are only two feet
and three palms high; all the walls are a foot and
a palm thick. Upon these walls stand upright posts not less thick, in order
that they
may bear the heavy weight placed upon them, and they are covered
with
lute; these posts support the sloping chimney and penetrate through
the
roof. Moreover, not only the ribs of the chimney, but also the rafters,
are
covered thickly with lute. The hearth of the furnace is six feet
long on each side, is sloping, and
is paved with bricks. The cakes of copper
are placed in the furnace and heated in the
following way. They are first of
all placed in the furnace in rows, with as many small
stones the size of an egg
between, so that the heat of the fire can
penetrate through the spaces between
them; indeed, those cakes which
are placed at the bottom of the crucible are
each raised upon half a
brick for the same reason. But lest the last row,
which lies against the mouth of the furnace,
should fall out, against the mouth
are placed iron plates, or the
copper cakes which are the first taken from the
crucible when copper is
made, and against them are laid exhausted liquation
cakes or rocks. Then charcoal is thrown on the cakes, and then live coals;
at first the
cakes are heated by a gentle fire, and afterward more charcoal is
added
to them until it is at times three-quarters of a foot deep. A fiercer fire
is certainly required to heat the hard cakes of copper
than the fragile ones. When the cakes have been sufficiently heated, which usually occurs within
the space of about two hours, the exhausted liquation cakes or the
rocks
and the iron plate are removed from the mouth of the furnace. Then the
hot cakes are taken out row after row with a two-pronged
rabble, such as the
one which is used by those who “dry”
the exhausted liquation cakes. Then the first cake is laid upon the exhausted liquation cakes, and beaten by
two workmen with hammers until it breaks; the hotter the cakes are, the
then they bend into the shape of copper basins. When the first cake has
been broken, the second is put on to the other
fragments and beaten until it
breaks into pieces, and the rest of the
cakes are broken up in the same manner
in due order. The head of the hammer is three palms long and one wide,
and sharpened
at both ends, and its handle is of wood three feet long. When they have been broken by the stamp, if cold, or with hammers if hot,
the fragments of copper or the cakes are carried into the store-room
for
copper.
A—BACK WALL. B—WALLS AT THE SIDES. C—UPRIGHT POSTS.
D—CHIMNEY.
E—THE CAKES ARRANGED. F—IRON PLATES.
G—ROCKS. H—RABBLE WITH TWO
PRONGS. I—HAMMERS.
The foreman of the works, according to the different proportions of
silver in each
he
could not separate the silver from the copper.
quarters of a
portions,
and a
lead—that is, that from which the
silver has not yet been separated—is
added, to the amount of half
a
a whole and a half, in such a way that there may be in the
copper-lead alloy
some one of the proportions of silver which I have
just mentioned, which is
the first alloy. To this “first” alloy is added such a weight of de-silverized
lead or litharge as is required to make out of all of these a single
liquation cake
that will contain approximately two
from one hundred and thirty
are made, a greater proportion of litharge than of de-silverized lead
is added
as a supplement. Since four cakes of this kind are placed at the same time
into the
furnace in which the silver and lead is liquated from copper, there
will be in all the cakes three
of lead. When the lead has been liquated from the copper, it weighs six
and almost a Only seven
exhausted liquation cakes and in that
copper-lead alloy which we call
“liquation thorns”; they
are not called by this name so much because they
have sharp points as
because they are base. If in three-quarters of a
pondíum
of silver, then so
much rich lead must be added as to make in the copper and
lead alloy
one of the proportions of silver which I have already mentioned. This is the “second” alloy.
To this is again to be added as great a weight
alloy a liquation cake containing two and a quarter
in which manner in four of these cakes there will be three
copper and nine The lead which liquates from these
cakes weighs seven
a quarter of a About seven
thorns, if we may be allowed to make common the old name (
and
bestow it upon a new substance. If in three-quarters of a
of copper there is less than three-quarters of a
and a
of the proportions of silver in
the copper-lead alloy above mentioned; this
is the “third”
alloy. To this is added such an amount of de-silverized lead
or of litharge,
that a liquation cake made from it contains in all two and
three-quarters In this manner four such cakes will
contain three The lead which these cakes liquate, when they are melted in the furnace,
weighs about nine
a quarter of a
silver remain in the exhausted liquation cakes and in the liquation
thorns. If, however, in three-quarters of a
ten-twelfths of a
then such a proportion of rich lead is added as will produce in the
copper-lead
alloy one of the proportions of silver which I mentioned
above; this is the
“fourth” alloy. To this is added such a weight of de-silverized lead or of
litharge,
that a liquation cake made from it contains three
twelve The lead which is liquated therefrom weighs
about ten
of a
seven
cakes and in the liquation
thorns.
Against the second long wall in the second part of the building, whose
area is eighty feet long by thirty-nine feet wide, are four furnaces in
which
the copper is alloyed with lead, and six furnaces in which
“slags” are re
smelted. The interior of the first kind of furnace is a foot and three palms wide,
two feet three digits long; and of the second is a foot and a palm wide
and a foot
three palms and a digit long. The side walls of these furnaces are the same
height as the furnaces in
which gold or silver ores are smelted. As the whole
room is divided into two parts by upright posts, the front
part must have,
first, two furnaces in which “slags” are
re-melted; second, two furnaces in
which copper is alloyed with lead;
and third, one furnace in which “slags” are
re-melted. The back part of the room has first, one furnace in which “slags”
are re-melted; next, two furnaces in which copper is alloyed with lead;
and
third, two furnaces in which “slags” are re-melted. Each of these is six feet
distant from the next; on the right side of
the first is a space of three feet
and two palms, and on the left side
of the last one of seven feet. Each pair of
furnaces has a common door, six feet high and a cubit wide,
but the first and
the tenth furnace each has one of its own. Each of the furnaces is set in an arch
of its own in the back wall, and
in front has a forehearth pit; this is filled with
a powder compound
rammed down and compressed in order to make a crucible. Under each furnace is a hidden receptacle for the moisture,
vent is made through the
back wall toward the right, which allows the
vapour to escape. Finally, to the right, in front, is the copper mould into
which the
copper-lead alloy is poured from the forehearth, in order that
liquation cakes of equal weight may be made. This copper mould is a digit
thick, its interior is two feet in diameter
and six digits deep. Behind the
second long wall are ten pairs of bellows, two machines for
compressing them,
and twenty instruments for inflating them. The way in which these should
be made may be understood from Book
IX.
The smelter, when he alloys copper with lead, with his hand throws into
the heated furnace, first the large fragments of copper, then a
basketful of
charcoal, then the smaller fragments of copper. When the copper is melted
and begins to run out of the tap-hole into the
forehearth, he throws litharge
into the furnace, and, lest part of it
should fly away, he first throws
charcoal over it, and lastly lead. As soon as he has thrown into the furnace
the copper and the lead, from
which alloy the first liquation cake is made, he
again throws in a
basket of charcoal, and then fragments of copper are thrown
over them,
from which the second cake may be made. Afterward with a
rabble he skims the “slag” from the copper
and lead as they flow into the
forehearth. Such a rabble is a board into which an iron bar is fixed; the
and a half digits thick; the iron bar is three
feet long, and the wooden
handle inserted into it is two and a half
feet long. While he purges the
alloy and pours it out with a ladle into the copper
mould, the fragments of
copper from which he is to make the second cake
are melting. As soon as
this begins to run down he again throws in litharge, and when
he has put on
more charcoal he adds the lead. This operation he repeats until thirty
liquation cakes have been made,
on which work he expends nine hours, or at
most ten; if more than
thirty cakes must be made, then he is paid for
another shift when he
has made an extra thirty.
At the same time that he pours the copper-lead alloy into the copper
mould, he also pours water slowly into the top of the mould. Then, with a
cleft stick, he takes a hook and puts its straight stem
into the molten cake. The hook itself is a digit and a half thick; its straight stem is two palms
long and two digits wide and thick. Afterward he pours more water over the
cakes. When they are cold he places an iron ring in the hook of the chain
A—FURNACE IN WHICH “SLAGS” ARE RE-SMELTED. B—FURNACE
IN WHICH COPPER IS
ALLOYED WITH LEAD. C—DOOR.
D—FORE-HEARTHS ON THE GROUND. E—COPPER
MOULDS.
F—RABBLE. G—HOOK. H—CLEFT STICK. I—ARM OF THE CRANE.
K—THE HOOK OF ITS CHAIN.
is six
digits, and it is about a digit and a half thick; the ring is then engaged
in the hook whose straight stem is in the cake, and thus the cake is
raised from
the mould and put into its place.
The copper and lead, when thus melted, yield a small amount of
“slag”
and
much litharge. The litharge does not cohere, but falls to pieces like the
residues from
malt from which beer is made.
in white ashes, and to the
sides of the furnace adheres
In this practical manner lead is alloyed with copper in which there is but
a moderate portion of silver. If, however, there is much silver in it, as, for
instance, two
weighs one hundred and thirty-three and a third
forty-six
pondíum
of which
there is a third of a
uncía. In this manner three liquation cakes are made, which contain
altogether
three
lead, when it has been liquated from the copper, weighs seven
and in each
and a
sixth and more than a
liquation cakes, and in the liquation thorns, there
remains a third of a
the lead a third of a
cake one and a half
of silver. In the exhausted liquation cakes there remain a third of a
and a
If there be in the copper only a minute proportion of silver, it cannot be
separated easily until it has been re-melted in other furnaces, so that
in
the “bottoms” there remains more silver and in the
“tops” less.
A—FURNACE. B—FOREHEARTH. C—DIPPING-POT.
D—CAKES.
furnace, vaulted with unbaked bricks, is similar to an
oven, and also to the
cupellation furnace, in which the lead is
separated from silver, which I described
in the last book. The crucible is made of ashes, in the same manner as
the building, is the mouth out of which the re-melted copper flows into
a
forehearth and a dipping-pot. On the left side of the mouth is an aperture,
through which beech-wood
may be put into the furnace to feed the fire. If
in a
silver, or
a quarter of a
re-melted at the same time thirty-eight
there remain in each For example, if in each
copper not yet re-melted, there is a quarter of
a
then the thirty-eight
total of
eleven Since from fifteen
of re-melted copper there was a total of four and a
third
of
silver, there remain only two and a third Thus there is left in the
“bottoms,” weighing twenty-three
quarter Therefore, each
third of a In order that the master may be more certain of the number of
of
copper in the “bottoms,” he weighs the “tops” that
have been drawn
off from it; the “tops” were first drawn
off into the dipping-pot, and cakes
were made from them. Fourteen hours are expended on the work of thus
dividing the copper. The “bottoms,” when a certain weight of lead has
been added
to them, of which alloy I shall soon speak, are melted in
the blast
furnace; liquation cakes are then made, and the silver is afterward
separated from the copper. The “tops” are subsequently melted
in the blast furnace, and
re-melted in the refining furnace, in order that
red copper shall be
made
the blast furnace,
and then again in the refining furnace, that therefrom But when the copper, yellow or red or
íum
it,
and from it they make at least twenty, and at most thirty-five,
pondía. About twenty-two
ten of yellow
copper and eight of red, are simultaneously placed in this latter
furnace and smelted, in order that they may be made into refined
copper.
The copper “bottoms” are alloyed in three different ways with
lead.
First, five-eights
of a
quarters
from this, therefore two and a half
tumpondíaInasmuch as in each
dium
of the copper ten-twelfths of a
pondía
a
and a half of
silver. There is also added seven
lead, in each
in the four cakes of copper-lead alloy there is a
total of a
a In each single
liquated from the
copper, there is an
we call “poor”
argentiferous lead, because it contains but little silver. But
as five cakes of that kind are placed together in the furnace, they
liquate
from them usually as much as nine and three-quarters Of the liquation
thorns there remain three
there are three
exhausted liquation cakes, each
uncía Inasmuch as in a
“bottoms” there is a third
of a
cakes there must be more than one and a
half
silver.
Then, again, from another two and a half
“bottoms,” together with eleven
are made. If in each
silver, there would be in the whole of the
sixths of a To this copper is added eight
pondíaThere is also added three
pondíumTherefore, four liquation
cakes contain a total of a
thus each
contains an
“medium” silver-lead.
Then, again, from another two and a half
“bottoms,” together with eleven
liquation cakes. If in each
third of a
sixths of a To this is added nine
of medium silver-lead, each
a
half and a
uncíaAnd likewise they add two
poor silver-lead, in each of which there is an
Therefore the four liquation cakes contain two and a third
Each
contains a sixth of a
This
alloy we call “rich” silver-lead; it is carried to the
cupellation furnace,
in which lead is separated from silver. I have now mentioned in how many
ways copper containing various
proportions of silver is alloyed with lead,
and how they are melted
together in the furnace and run into the casting pan.
Now I will speak of the method by which lead is liquated from copper
simultaneously with the silver. The liquation cakes are raised from the
ground with the crane, and
placed on the copper plates of the furnaces. The
hook of the chain let down from the arm of the crane, is inserted in
a
ring of the tongs, one jaw of which has a tooth; a ring is engaged in
each
of the handles of the tongs, and these two rings are engaged in a
third, in
which the hook of the chain is inserted. The tooth on the one jaw of the
tongs is struck by a hammer, and driven
into the hole in the cake, at the point
of
the copper mould; the other jaw of the tongs, which has no tooth,
squeezes the cake, lest the tooth should fall out of it; the tongs are
one and
a half feet long, each ring is a digit and a half thick, and
the inside is a palm
and two digits in diameter. Those cranes by which the cakes are lifted out
of the copper pans and
placed on the ground, and lifted up again from there
and placed in the
furnaces, are two in number—one in the middle space
between the
third transverse wall and the two upright posts, and the other in
A—CRANE. B—DRUM CONSISTING OF RUNDLES. C—TOOTHED DRUM.
D—TROLLEY
AND ITS WHEELS. E—TRIANGULAR BOARD.
F—CAKES. G—CHAIN OF THE CRANE.
H—ITS HOOK.
I—RING. K—THE TONGS.
the middle space between the same posts
and the seventh transverse wall. The rectangular crane-post of both of these is two feet wide and thick, and
is eighteen feet from the third long wall, and nineteen from the second
long
wall. There are two drums in the framework of each—one drum consisting
of rundles, the other being toothed. The crane-arm of each extends seventeen
feet, three palms and as many
digits from the post. The trolley of each
crane is two feet and as many palms long, a foot and
two digits wide, and a
palm and two digits thick; but where it runs
between the beams of the
crane-arm it is three digits wide and a palm
thick; it has five notches, in
larger than the
rest. The notches in which the small wheels turn are two
palms long and as
much as a palm wide; those wheels are a palm wide and
a palm and two
digits in diameter; four of the notches are near the four
corners of
the trolley; the fifth notch is between the two front ones, and
it is
two palms back from the front. Its pulley is larger than the rest, and
turns in its own notch; it is
three palms in diameter and one palm wide,
and grooved on the
circumference, so that the iron chain may run in the
groove. The trolley has two small axles, to the one in front are fastened
three,
and to the one at the back, the two wheels; two wheels run on the
one
beam of the crane-arm, and two on the other; the fifth wheel, which is
larger than the others, runs between those two beams. Those people who
have no cranes place the cakes on a triangular board,
to which iron cleats
are affixed, so that it will last longer; the
board has three iron chains,
which are fixed in an iron ring at the
top; two workmen pass a pole through
the ring and carry it on their
shoulders, and thus take the cake to the furnace
in which silver is
separated from copper.
From the vicinity of the furnaces in which copper is mixed with lead and
the “slags” are re-melted, to the third long wall, are
likewise ten furnaces,
in which silver mixed with lead is separated
from copper. If this space is
eighty feet and two palms long, and the third long wall
has in the centre a
door three feet and two palms wide, then the spaces
remaining at either side
of the door will be thirty-eight feet and two
palms; and if each of the furnaces
occupies four feet and a palm, then
the interval between each furnace and
the next one must be a foot and
three palms; thus the width of the five
furnaces and four interspaces
will be twenty-eight feet and a palm. There
fore, there remain ten feet and a palm, which measurement is
so divided
that there are five feet and two digits between the first
furnace and
the transverse wall, and as many feet and digits between
the fifth furnace
and the door; similarly in the other part of the
space from the door to the
sixth furnace, there must be five feet and
two digits, and from the tenth
furnace to the seventh transverse wall,
likewise, five feet and two digits. The door is six feet and two palms high; through it the foreman of the
and the
workmen enter the store-room in which the silver-lead alloy is kept.
Each furnace has a bed, a hearth, a rear wall, two sides and a front,
and a receiving-pit. The bed consists of two sole-stones, four rectangular
stones, and two
copper plates; the sole-stones are five feet and a palm
long, a cubit
wide, a foot and a palm thick, and they are sunk into the ground,
so
that they emerge a palm and two digits; they are distant from each other
about three palms, yet the distance is narrower at the back than the
front. Each of the rectangular stones is two feet and as many palms long, a cubit
wide, and a cubit thick at the outer edge, and a foot and a palm thick
on the
inner edge which faces the hearth, thus they form an incline, so
that there is a
slope to the copper plates which are laid upon them. Two of these rectang
ular stones are placed on one sole-stone; a
hole is cut in the upper edge of
each, and into the holes are placed
iron clamps, and lead is poured in; they
front
the sole-stones project to the same extent; if rectangular stones are
not available, bricks are laid in their place. The copper plates are four feet
two palms and as many digits long, a
cubit wide, and a palm thick; each
edge has a protuberance, one at the
front end, the other at the back; these
are a palm and three digits
long, and a palm wide and thick. The plates are
so laid upon the rectangular stones that their rear ends
are three digits from
the third long wall; the stones project beyond
the plate the same number
of digits in front, and a palm and three
digits at the sides. When the plates
have been joined, the groove which is between the
protuberances is a palm
and three digits wide, and four feet long, and
through it flows the silver-lead
which liquates from the cakes. When the plates are corroded either by the
fire or by the silver-lead,
which often adheres to them in the form of stalac
tites, and is
chipped off, they are exchanged, the right one being placed to the
left, and the left one, on the contrary, to the right; but the left
side of the
plates, which, when the fusion of the copper took place,
came into contact
with the copper, must lie flat; so that when the
exchange of the plates has
been carried out, the protuberances, which
are thus on the underside, raise
the plate from the stones, and they
have to be partially chipped off, lest they
should prove an impediment
to the work; and in each of their places is
laid a piece of iron, three
palms long, a digit thick at both ends, and a palm
thick in the centre
for the length of a palm and three digits.
The passage under the plates between the rectangular stones is a foot
wide at the back, and a foot and a palm wide at the front, for it
gradually
widens out. The hearth, which is between the sole-stones, is covered with a
bed of
hearth-lead, taken from the crucible in which lead is separated from
silver. The rear end is the highest, and should be so high that it reaches to
within six digits of the plates, from which point it slopes down evenly
to the
front end, so that the argentiferous lead alloy which liquates
from the cakes
can flow into the receiving-pit. The wall built against the third long wall
in order to protect it from
injury by fire, is constructed of bricks joined
together with lute, and
stands on the copper plates; this wall is two feet, a
palm and two
digits high, two palms thick, and three feet, a palm and three
digits
wide at the bottom, for it reaches across both of them; at the top it is
three feet wide, for it rises up obliquely on each side. At each side of this wall,
at a height of a palm and two digits above
the top of it, there is inserted in a
hole in the third long wall a
hooked iron rod, fastened in with molten lead;
the rod projects two
palms from the wall, and is two digits wide and one
digit thick; it has
two hooks, the one at the side, the other at the end. Both of these hooks open toward the wall, and both are a digit thick, and
both are inserted in the last, or the adjacent, links of a short iron
chain. This
chain consists of four links, each of which is a palm and a digit
long and half
a digit thick; the first link is engaged in the first
hole in a long iron rod, and
one or other of the remaining three links
engages the hook of the hooked rod. The two long rods are three feet and as many palms and digits long, two
digits wide, and one digit thick; both ends of both of these rods have
holes,
A—SOLE-STONES. B—RECTANGULAR STONES. C—COPPER PLATES.
D—FRONT PANEL.
E—SIDE PANELS. F—BAR. G—FRONT
END OF THE LONG IRON RODS. H—SHORT CHAIN.
I—HOOKED ROD.
K—WALL WHICH PROTECTS THE THIRD LONG WALL FROM INJURY BY
FIRE.
L—THIRD LONG WALL. M—FEET OF THE PANELS. N—IRON BLOCKS.
O—CAKES.
P—HEARTH. Q—RECEIVING-PIT.
the first link of the chain as I have stated; the hole at the
front end is two
digits and a half long and a digit and a half wide. This end of each rod
is made three digits wide, while for the rest of
its length it is only two digits,
and at the back it is two and a half
digits. Into the front hole of each rod is
driven an iron bar, which is three
feet and two palms long, two digits wide
and one thick; in the end of
this bar are five small square holes, two-thirds
of a digit square;
each hole is distant from the other half a digit, the first
being at a
distance of about a digit from the end. Into one of these holes the
refiner drives an iron pin; if he should
desire to make the furnace narrower,
then he drives it into the last
hole; if he should desire to widen it, then into
the first hole; if he
should desire to contract it moderately, then into one
of the middle
holes. For the same reason, therefore, the hook is sometimes
inserted into the
last link of the chain, and sometimes into the third or the
second. The furnace is widened when many cakes are put into it, and
con
tracted when there are but few, but to put in more than five is
neither usual
nor possible; indeed, it is because of thin cakes that
the walls are contracted. The bar has a hump, which projects a digit on each side at the back, of the
same width and thickness as itself. These humps project, lest the bar should
slip through the hole of the
right-hand rod, in which it remains fixed when
it, together with the
rods, is not pressing upon the furnace walls.
There are three panels to the furnace—two at the sides, one in front
and another at the back. Those which are at the sides are three feet
and as many palms and two
digits long, and two feet high; the front one is
two feet and a palm
and three digits long, and, like the side ones, two feet
high. Each consists of iron bars, of feet, and of iron plates.
Those which are
at the side have seven bars, the lower and upper of
which are of the same
length as the panels; the former holds up the
upright bars; the latter is
placed upon them; the uprights are five in
number, and have the same height
as the panels; the middle ones are
inserted into holes in the upper and lower
bars; the outer ones are
made of one and the same bar as the lower and
upper ones. They are two digits wide and one thick.
The front panel has
five bars; the lower one holds similar uprights, but
there are three of them
only; the upper bar is placed on them. Each of these panels has two feet
fixed at each end of the lower bar,
and these are two palms long, one wide,
and a digit thick. The iron plates are fastened to the inner side of the bars
with iron
wire, and they are covered with lute, so that they may last longer
and
may be uninjured by the fire. There are, besides, iron blocks three palms
long, one wide, and a digit
and a half thick; the upper surface of these is
somewhat hollowed out,
so that the cakes may stand in them; these iron
blocks are dipped into
a vessel in which there is clay mixed with water, and
they are used
only for placing under the cakes of copper and lead alloy made
in the
furnaces. There is more silver in these than in those which are
made of liquation
thorns, or furnace accretions, or re-melted “slags.” Two
iron blocks are placed under each cake, in order that, by raising it
up, the fire
may bring more force to bear upon it; the one is put on
the right bed-plate,
A—FURNACE IN WHICH THE OPERATION OF LIQUATION IS BEING PERFORMED.
B—FURNACE IN WHICH IT IS NOT BEING PERFORMED.
C—RECEIVING-PIT. D—MOULDS.
E—CAKES. F—LIQUATION
THORNS.Finally, outside the hearth is the receiving-pit, which
is a foot wide
and three palms deep; when this is worn away it is restored
with lute
alone, which easily retains the lead alloy.
If four liquation cakes are placed on the plates of each furnace, then the
iron blocks are laid under them; but if the cakes are made from copper
“bottoms,” or from liquation thorns, or from the accretions
or “slags,” of
which I have partly written above and will
further describe a little later,
there are five of them, and because
they are not so large and heavy, no blocks
are placed under them. Pieces of charcoal six digits long are laid between the
cakes, lest they
should fall one against the other, or lest the last one should
fall
against the wall which protects the third long wall from injury by fire. In
the middle empty spaces, long and large pieces of charcoal are
likewise laid. Then when the panels have been set up, and the bar has been closed, the
furnace is filled with small charcoal, and a wicker basket full of
charcoal is
thrown into the receiving-pit, and over that are thrown
live coals; soon
afterward the burning coal, lifted up in a shovel, is
spread over all parts of
the furnace, so that the charcoal in it may be
kindled; any charcoal which
remains in the receiving-pit is thrown into
the passage, so that it may likewise
be heated. If this has not been done, the silver-lead alloy liquated from the
cakes
is frozen by the coldness of the passage, and does not run down into the
receiving-pit.
After a quarter of an hour the cakes begin to drip silver-lead alloy,
which runs down through the
openings between the copper plates into the
passage. When the long pieces of charcoal have burned up, if the cakes
lean
toward the wall, they are placed upright again with a hooked bar, but
if they lean toward the front bar they are propped up by charcoal;
more
over, if some cakes shrink more than the rest, charcoal is
added to the former
and not to the others. The silver drips together with the lead, for both melt
more rapidly than
copper. The liquation thorns do not flow away, but remain
in the passage, and
should be turned over frequently with a hooked bar, in
order that the
silver-lead may liquate away from them and flow down into
the receiving
pit; that which remains is again melted in the blast furnace,
while
that which flows into the receiving pit is at once carried with the
remain
silver. The hooked bar has an iron handle two feet long, in which is set a
wooden one four feet long. The silver-lead which runs out into the receiving
pit is poured out
by the refiner with a bronze ladle into eight copper moulds,
which are
two palms and three digits in diameter; these are first smeared
with a
lute wash so that the cakes of silver-lead may more easily fall out
when they are turned over. If the supply of moulds fails because the silver
lead flows down too
rapidly into the receiving-pit, then water is poured on them,
in order
that the cakes may cool and be taken out of them more rapidly;
thus the
same moulds may be used again immediately; if no such necessity
urges
the refiner, he washes over the empty moulds with a lute wash. The
ladle is exactly similar to that which is used in pouring out the
metals that
are melted in the blast furnace. When all the silver-lead has run down from
the passage into the
receiving-pit, and has been poured out into copper
moulds, the thorns
are drawn out of the passage into the receiving-pit
with a rabble;
afterward they are raked on to the ground from the receiving
pit,
thrown with a shovel into a wheelbarrow, and, having been conveyed
away
to a heap, are melted once again. The blade of the rabble is two palms
and as many digits long, two palms
and a digit wide, and joined to its
back is an iron handle three feet
long; into the iron handle is inserted a
wooden one as many feet in
length.
The residue cakes, after the silver-lead has been liquated from the
copper, are called “exhausted liquation cakes” (
thus smelted they appear to be dried up. By placing a crowbar under the
cakes they are raised up, seized with
tongs, and placed in the wheelbarrow;
they are then conveyed away to
the furnace in which they are “dried.”
The crowbar is
somewhat similar to those generally used to chip off the
accretions
that adhere to the walls of the blast furnace. The tongs are two
and a half feet long. With the same crowbar the stalactites are chipped off
from the copper
plates from which they hang, and with the same instrument
the iron
blocks are struck off the exhausted liquation cakes to which they
adhere. The refiner has performed his day's task when he has liquated the
silver-lead from sixteen of the large cakes and twenty of the smaller
ones;
if he liquates more than this, he is paid separately for it at
the price for
extraordinary work.
Silver, or lead mixed with silver, which we call
the above
method from copper. This silver-lead is carried to the cupellation
furnace, in which lead is
separated from silver; of these methods I will
mention only one,
because in the previous book I have explained them in
detail. Amongst us some years ago only forty-four
lead
and one of copper were melted together in the cupellation furnaces,
but
now they melt forty-six
manner they make about one hundred
and ten
litharge and thirty of hearth-lead. But in all these methods the silver which
equally with
the lead, will be changed partly into litharge and partly into
hearth-lead.
margin of the
crucible with a hooked bar.
The work of “drying” is distributed into four operations, which
are
performed in four days. On the first—as likewise on the other three days—the
master
begins at the fourth hour of the morning, and with his assistant chips
A—CAKES. B—HAMMER.
off the stalactites from the exhausted
liquation cakes. They then carry the
cakes to the furnace, and put the stalactites upon
the heap of liquation
thorns. The head of the chipping hammer is three palms and as many digits
wooden handle is four feet long.
The master throws pulverised earth into a small vessel, sprinkles water
over it, and mixes it; this he pours over the whole hearth, and
sprinkles
charcoal dust over it to the thickness of a digit. If he should neglect this,
the copper, settling in the passages, would
adhere to the copper bed-plates,
from which it can be chipped off only
with difficulty; or else it would adhere
to the bricks, if the hearth
was covered with them, and when the copper is
chipped off these they
are easily broken. On the second day, at the same
time, the master arranges bricks in ten
rows; in this manner twelve
passages are made. The first two rows of bricks are between the first and
the second
openings on the right of the furnace; the next three rows are
between
the second and third openings, the following three rows are
between the
third and the fourth openings, and the last two rows between
the fourth
and fifth openings. These bricks are a foot and a palm long, two
palms and a digit wide, and
a palm and two digits thick; there are seven of
these thick bricks in a
row, so there are seventy all together. Then on the
first three rows of bricks they lay exhausted liquation
cakes and a layer five
digits thick of large charcoal; then in a
similar way more exhausted
liquation cakes are laid upon the other
bricks, and charcoal is thrown upon
them; in this manner seventy
hearth of the furnace. But if half of this weight, or a little more, is to be
“dried,” then four rows of bricks will suffice. Those who dry exhausted
liquation cakesA place is left in the front
part of the furnace for the topmost cakes
removed from the forehearth in
which copper is made, these being more
suitable for supporting the exhausted
liquation cakes than are iron
plates; indeed, if the former cakes drip copper
from the heat, this can
be taken back with the liquation thorns to the first
furnace, but
melted iron is of no use to us in these matters. When the cakes
of this kind have been placed in front of the exhausted
liquation cakes, the
workman inserts the iron bar into the holes on the
inside of the wall, which
are at a height of three palms and two digits
above the hearth; the hole to
the left penetrates through into the
wall, so that the bar may be pushed back This bar is round, eight feet long and two digits in diameter;
on the
right side it has a haft made of iron, which is about a foot from the
right end; the aperture in this haft is a palm wide, two digits high,
and a
digit thick. The bar holds the exhausted liquation cakes opposite, lest they
should
fall down. When the operation of “drying” is completed, a work
man
draws out this bar with a crook which he inserts into the haft, as I will
explain hereafter.
In order that one should understand those things of which I have spoken,
and concerning which I am about to speak, it is necessary for me to
give some
information beforehand about the furnace and how it is to be
made. It stands
nine feet from the fourth long wall, and as far from the wall
which is between
the second and fourth transverse walls. It consists of walls, an arch, a chimney,
an interior wall, and a
hearth; the two walls are at the sides; and they are
eleven feet three
palms and two digits long, and where they support the
chimney they are
eight feet and a palm high. At the front of the arch they
are only seven feet high; they are two
feet three palms and two digits
thick, and are made either of rock or
of bricks; the distance between them
is eight feet, a palm and two
digits. There are two of the arches, for the
space at the rear between the walls
is also arched from the ground, in order
that it may be able to support
the chimney; the foundations of these
arches are the walls of the
furnace; the span of the arch has the same
length as the space between
the walls; the top of the arch is five feet, a palm
and two digits
high. In the rear arch there is a wall made of bricks joined
with lime; this
wall at a height of a foot and three palms from the ground
has five
vent-holes, which are two palms and a digit high, a palm and a digit
wide, of which the first is near the right interior wall, and the last
near the
left interior wall, the remaining three in the intervening
space; these vent
holes penetrate through the interior of the wall
which is in the arch. Half-bricks can be placed over the vent-holes, lest too much air should be
drawn into the furnace, and they can be taken out at times, in order
that he
who is “drying” the exhausted liquation cakes may
inspect the passages,
as they are called, to see whether the cakes are
being properly “dried.”
The front arch is three feet two
palms distant from the rear one; this arch
is the same thickness as
that of the rear arch, but the span is six feet wide;
A—SIDE WALLS. B—FRONT ARCH. C—REAR ARCH. D—WALL IN
THE REAR ARCH.
E—INNER WALL. F—VENT HOLES. G—CHIMNEY.
H—HEARTH. I—TANK. K—PIPE.
L—PLUG. M—IRON
DOOR. N—TRANSVERSE BARS. O—UPRIGHT BARS. P—PLATES.
Q—RINGS OF THE BARS. R—CHAINS. S—ROWS OF BRICKS.
T—BAR. V—ITS HAFT.
X—COPPER BED-PLATES.A chimney
is built upon the arches and the walls, and is made of bricks
joined
together with lime; it is thirty-six feet high and penetrates
through the
roof. The interior wall is built against the rear arch and both the side
walls, from which it juts out a foot; it is three feet and the same
number
of palms high, three palms thick, and is made of bricks joined
together
with lute and smeared thickly with lute, sloping up to the
height of
a foot above it. This wall is a kind of shield, for it protects the exterior
walls from
the heat of the fire, which is apt to injure them; the latter
can
not be easily re-made, while the former can be repaired with
little work.
The hearth is made of lute, and is covered either with copper plates,
such as those of the furnaces in which silver is liquated from copper,
although
they have no protuberances, or it may be covered with bricks,
if the owners
are unwilling to incur the expense of copper plates. The wider part of the
hearth is made sloping in such a manner that the
rear end reaches as high as
the five vent-holes, and the front end of
the hearth is so low that the back
of the front arch is four feet,
three palms and as many digits above it,
and the front five feet, three
palms and as many digits. The hearth beyond
the furnaces is paved with bricks for a distance of
six feet. Near the
furnace, against the fourth long wall, is a tank thirteen feet
and a palm
long, four feet wide, and a foot and three palms deep. It is lined on all sides
with planks, lest the earth should fall into
it; on one side the water flows
in through pipes, and on the other, if
the plug be pulled out, it soaks into the
earth; into this tank of
water are thrown the cakes of copper from which
the silver and lead
have been separated. The fore part of the front furnace
arch should be partly closed with an
iron door; the bottom of this door is
six feet and two digits wide; the
upper part is somewhat rounded, and at
the highest point, which is in
the middle, it is three feet and two palms high. It is made of iron bars, with plates fastened to them with iron wire, there
being seven bars—three transverse and four upright—each of
which is two
digits wide and half a digit thick. The lowest transverse bar is six feet and
two palms long; the middle one
has the same length; the upper one is
curved and higher at the centre,
and thus longer than the other two. The
upright bars are two feet distant from one another; both the outer
ones are
two feet and as many palms high; but the centre ones are three
feet and two
palms. They project from the upper curved transverse bar and have holes,
in
which are inserted the hooks of small chains two feet long; the topmost
links of these chains are engaged in the ring of a third chain, which,
when
extended, reaches to one end of a beam which is somewhat cut out. The chain
then turns around the beam, and again hanging down, the hook
in the other end
is fastened in one of the links. This beam is eleven feet long, a palm and two
digits wide, a palm thick,
and turns on an iron axle fixed in a near-by timber;
the rear end of
the beam has an iron pin, which is three palms and a digit long,
and
which penetrates through it where it lies under a timber, and projects
from it a palm and two digits on one side, and three digits on the
other side. At this point the pin is perforated, in order that a ring may be fixed in it
thick, while the other round end is thicker
than a digit. When the door is
to be shut, this pin lies under the timber and holds
the door so that it cannot
fall; the pin likewise prevents the
rectangular iron band which encircles the
end of the beam, and into
which is inserted the ring of a long hook, from
falling from the end. The lowest link of an iron chain, which is six feet long,
is inserted in
the ring of a staple driven into the right wall of the furnace,
and
fixed firmly by filling in with molten lead. The hook suspended at the
top from the ring should be inserted in one of
these lower links, when the
door is to be raised; when the door is to
be let down, the hook is taken out
of that link and put into one of the
upper links.
On the third day the master sets about the principal operation.
First
he throws a basketful of charcoals on to the ground in front of
the hearth,
and kindles them by adding live coals, and having thrown
live coals on to the
cakes placed within, he spreads them equally all
over with an iron shovel. The blade of the shovel is three palms and a digit long, and three palms
wide;
its iron handle is two palms long, and the wooden one ten feet
long, so that
it can reach to the rear wall of the furnace. The exhausted liquation cakes
become incandescent in an hour and a half,
if the copper was good and hard,
A—THE DOOR LET DOWN. B—BAR. C—EXHAUSTED LIQUATION CAKES.
D—BRICKS.
E—TONGS.The workman adds charcoal to
them where he sees it is needed, throwing
it into the furnace through the
openings on both sides between the side
walls and the closed door. This open
ing is a foot and a palm wide. He lets down the door, and when the “slags”
begin to flow he
opens the passages with a bar; this should take place after
five hours;
the door is let down over the upper open part of the arch for
two feet
and as many digits, so that the master can bear the violence of the
heat. When the cakes shrink, charcoal should not be added to them lest
they
should melt. If the cakes made from poor and fragile copper are
“dried”
with cakes made from good hard copper, very often the copper
so settles
into the passages that a bar thrust into them cannot penetrate
them. This bar is of iron, six feet and two palms long, into which a wooden
handle five feet long is inserted. The refiner draws off the “slags” with a
rabble from the
right side of the hearth. The blade of the rabble is made
of an iron plate a foot and a palm wide,
gradually narrowing toward the
handle; the blade is two palms high, its
iron handle is two feet long, and
the wooden handle set into it is ten
feet long.
When the exhausted liquation cakes have been “dried,” the master
A—THE DOOR RAISED. B—HOOKED BAR. C—TWO-PRONGED RAKE.
D—TONGS.
E—TANK.
inserted into the
haft of the bar he draws it through the hole in the left wall
from the
hole in the right wall; afterward he pushes it back and replaces it.
The master then takes out the exhausted liquation cakes nearest to him with
the iron hook; then he pulls out the cakes from the bricks. This hook is
two palms high, as many digits wide, and one thick; its
iron handle is two
feet long, and the wooden handle eleven feet long. There is also a two
pronged rake with which the “dried”
cakes are drawn over to the left side so
that they may be seized with
tongs; the prongs of the rake are pointed,
and are two palms long, as
many digits wide, and one digit thick; the iron
part of the handle is a
foot long, the wooden part nine feet long. The
“dried” cakes, taken out of the hearth by the master and
his assistants,
are seized with other tongs and thrown into the
rectangular tank, which is
almost filled with water. These tongs are two feet and three palms long,
both the handles are
round and more than a digit thick, and the ends are
bent for a palm and
two digits; both the jaws are a digit and a half wide
in front and
sharpened; at the back they are a digit thick, and then gradually
taper, and when closed, the interior is two palms and as many digits
wide.
The “dried” cakes which are dripping copper are not immediately
dipped
into the tank, because, if so, they burst in fragments and give
out a sound
like thunder. The cakes are afterward taken out of the tank with the
tongs, and laid
upon the two transverse planks on which the workmen stand;
the sooner
they are taken out the easier it is to chip off the copper that
has
become ash-coloured. Finally, the master, with a spade, raises up the
bricks a little from
the hearth, while they are still warm. The blade of the
spade is a palm and two digits long, the lower edge is
sharp, and is a palm
and a digit wide, the upper end a palm wide; its
handle is round, the iron
part being two feet long, and the wooden part
seven and a half feet long.
On the fourth day the master draws out the liquation thorns which
have
settled in the passages; they are much richer in silver than those
that
are made when the silver-lead is liquated from copper in the liquation
furnace. The “dried” cakes drip but little copper, but nearly all their
remaining silver-lead and the thorns consist of it, for, indeed, in one
of silver,
and there sometimes remain only three
chip off the metal adhering to the
bricks with a hammer, in order that it
may be melted again; others,
however, crush the bricks under the stamps
and wash them, and the
copper and lead thus collected is melted again. The
master, when he has taken these things away and put them in their
places,
has finished his day's work.
The assistants take the “dried” cakes out of the tank on the
next day, place them on an oak block, and first pound them with rounded
hammers in order that the ash-coloured copper may fall away from them,
the same kind of copper. The head of the round hammer is three palms and
a digit long; one end of
the head is round and two digits long and thick;
the other end is
chisel-shaped, and is two digits and a half long. The sharp
pointed hammer is the same length as the round hammer, but one
end is
pointed, the other end is square, and gradually tapers to a
point.
A—TANK. B—BOARD. C—TONGS. D—“DRIED” CAKES
TAKEN OUT OF THE TANKS.
E—BLOCK. F—ROUNDED HAMMER.
G—POINTED HAMMER.
The nature of copper is such that when it is “dried” it becomes
ash
coloured, and since this copper contains silver, it is smelted
again in the
blast furnaces.
I have described sufficiently the method by which exhausted liquation
cakes are “dried”; now I will speak of the method by which
they are made
into copper after they have been “dried.”
These cakes, in order that
they may recover the appearance of copper
which they have to some extent
lost, are melted in four furnaces, which
are placed against the second long
wall in the part of the building
between the second and third transverse
walls. This space is sixty-three feet and two palms long, and since each of
side of the first furnace, and on the left of the fourth,
are each three feet and
three palms wide, and the distance between the
second and third furnace is
six feet. In the middle of each of these three spaces is a door, a foot and
a half
wide and six feet high, and the middle one is common to the master
of
each of the furnaces. Each furnace has its own chimney, which rises
between the two long walls
mentioned above, and is supported by two arches
and a partition wall. The partition wall is between the two furnaces, and
is five feet long,
ten feet high, and two feet thick; in front of it is a pillar
belonging
in common to the front arches of the furnace on either side, which
is
two feet and as many palms thick, three feet and a half wide. The front
arch reaches from this common pillar to another pillar that is
common to the
side arch of the same furnace; this arch on the right
spans from the second
long wall to the same pillar, which is two feet
and as many palms wide and
thick at the bottom. The interior of the front arch is nine feet and a palm
wide, and eight
feet high at its highest point; the interior of the arch which
is on
the right side, is five feet and a palm wide, and of equal height to the
other, and both the arches are built of the same height as the
partition wall. Imposed upon these arches and the partition wall are the walls of the
chimney;
these slope upward, and thus contract, so that at the upper
part, where the
fumes are emitted, the opening is eight feet in length,
one foot and three
palms in width. The fourth wall of the chimney is built vertically upon the
second long
wall. As the partition wall is common to the two furnaces, so its
superstructure is common to the two chimneys. In this sensible manner
the chimney is built. At the front each furnace is six feet two palms long,
and three feet two
palms wide, and a cubit high; the back of each furnace
is against the
second long wall, the front being open. The first furnace is open
and sloping at the right side, so that the
slags may be drawn out; the left
side is against the partition wall,
and has a little wall built of bricks cemented
together with lute; this
little wall protects the partition wall from injury by
the fire. On the contrary, the second furnace has the left side open and
the right
side is against the partition wall, where also it has its own little wall
which protects the partition wall from the fire. The front of each furnace is
built of rectangular rocks; the interior of
it is filled up with earth. Then in
each of the furnaces at the rear, against the second long wall,
is an aperture
through an arch at the back, and in these are fixed the
copper pipes. Each
furnace has a round pit, two feet and as many palms wide, built
three feet
away from the partition wall. Finally, under the pit of the furnace, at a
depth of a cubit, is the
hidden receptacle for moisture, similar to the others,
whose vent
penetrates through the second long wall and slopes upward to
the right
from the first furnace, and to the left from the second. If copper
is to be made the next day, then the master cuts out the
crucible with a
spatula, the blade of which is three digits wide and as
many palms long, the
iron handle being two feet long and one and a half
digits in diameter; the
wooden handle inserted into it is round, five
feet long and two digits
in diameter. Then, with another cutting spatula, he makes the crucible
handle, partly of iron, partly of wood, is similar in every respect to
the first
one. Afterward he throws pulverised clay and charcoal into the crucible, pours
water over it, and sweeps it over with a broom into which a stick is
fixed. Then immediately he throws into the crucible a powder, made of two
wheelbarrowsful of sifted charcoal dust, as many wheelbarrowsful of
A—HEARTH OF THE FURNACE. B—CHIMNEY. C—COMMON PILLAR.
D—OTHER PILLARS.
THE PARTITION WALL IS BEHIND THE COMMON PILLAR
AND NOT TO BE SEEN. E—ARCHES.
F—LITTLE WALLS WHICH PROTECT
THE PARTITION WALL FROM INJURY BY THE FIRE.
G—CRUCIBLES.
H—SECOND LONG WALL. I—DOOR. K—SPATULA. L—THE OTHER
SPATULA. M—THE BROOM IN WHICH IS INSERTED A STICK.
N—PESTLES. O—WOODEN
MALLET. P—PLATE. Q—STONES.
R—IRON ROD.
pulverised clay likewise sifted, and six basketsful of
river sand which has
passed through a very fine sieve. This powder, like that used by smelters,
is sprinkled with water and
moistened before it is put into the crucible, so
that it may be
fashioned by the hands into shapes similar to snowballs. When it has been put in, the master first kneads it and makes it smooth with
his hands, and then pounds it with two wooden pestles, each of which is
a
cubit long; each pestle has a round head at each end, but one of
these is
a palm in diameter, the other three digits; both are thinner
in the middle,
so that they may be held in the hand. Then he again throws moistened
kneads it with his fists
and with the pestles; then, pushing upward and
pressing with his
fingers, he makes the edge of the crucible smooth. After the
crucible has been made smooth, he sprinkles in dry charcoal
dust, and again
pounds it with the same pestles, at first with the
narrow heads, and afterward
with the wider ones. Then he pounds the crucible with a wooden mallet
two feet long, both
heads of which are round and three digits in diameter;
its wooden
handle is two palms long, and one and a half digits in diameter. Finally, he throws into the crucible as much pure sifted ashes as both hands
can hold, and pours water into it, and, taking an old linen rag, he
smears
the crucible over with the wet ashes. The crucible is round and sloping.
If
copper is to be made from the best quality of “dried”
cakes, it is made two
feet wide and one deep, but if from other cakes,
it is made a cubit wide and
two palms deep. The master also has an iron band curved at both ends,
two palms long and
as many digits wide, and with this he cuts off the edges
of the
crucible if they are higher than is necessary. The copper pipe is
inclined, and projects three digits from the wall,
and has its upper end and
both sides smeared thick with lute, that it
may not be burned; but the under
side of the pipe is smeared thinly
with lute, for this side reaches almost to the
edge of the crucible,
and when the crucible is full the molten copper touches
it. The wall above the pipe is smeared over with lute, lest that should be
damaged. He does the same to the other side of an iron plate, which is a
foot and
three palms long and a foot high; this stands on stones near the
crucible at the side where the hearth slopes, in order that the slag
may run
out under it. Others do not place the plates upon stones, but cut out
of the plate
underneath a small piece, three digits long and three digits
wide; lest
the plate should fall, it is supported by an iron rod fixed in the
wall
at a height of two palms and the same number of digits, and it projects
from the wall three palms.
Then with an iron shovel, whose wooden handle is six feet long, he
throws live charcoal into the crucible; or else charcoal, kindled by
means
of a few live coals, is added to them. Over the live charcoal he lays “dried”
cakes, which, if they
were of copper of the first quality, weigh all together
three
of copper of the second quality, then two and a half
were of the third quality, then two
of copper of very superior quality, then they place upon it six
and
in this case they make the crucible wider and deeper.
“dried” cake is
placed at a distance of two palms from the pipe, the rest at
a greater
distance, and when the lower ones are melted the upper ones fall
down
and get nearer to the pipe; if they do not fall down they must
be
pushed with a shovel. The blade of the shovel is a foot long, three palms
and two digits wide,
the iron part of the handle is two palms long, the Round about the “dried” cakes are placed large
long pieces
of charcoal, and in the pipe are placed medium-sized pieces. When all these things have been arranged in this manner, the fire must be
more violently excited by the blast from the bellows. When the copper is
melting and the coals blaze, the master pushes an
iron bar into the middle
of them in order that they may receive the
air, and that the flame can force
its way out. This pointed bar is two and a half feet long, and its wooden
handle four
feet long. When the cakes are partly melted, the master, passing
out through the
door, inspects the crucible through the bronze pipe, and if he
should
find that too much of the “slag” is adhering to the mouth of the
pipe,
and thus impeding the blast of the bellows, he inserts the hooked
iron bar
into the pipe through the nozzle of the bellows, and, turning
this about the
mouth of the pipe, he removes the “slags”
from it. The hook on this bar
is two digits high; the iron part of the handle is
three feet long; the wooden
part is the same number of palms long. Now it is time to insert the bar
under the iron plate, in order that the
“slags” may flow out. When the
cakes, being all melted, have run into the crucible, he takes
out a sample of
copper with the third round bar, which is made wholly
of iron, and is three feet
long, a digit thick, and has a steel point
lest its pores should absorb the copper.
A—POINTED BAR. B—THIN COPPER LAYER. C—ANVIL.
D—HAMMER.
possible into the crucible through
the pipe between the two nozzles, and
takes out samples two, three, or
four times, until he finds that the copper is
perfectly refined. If the copper is good it adheres easily to the bar, and
two samples
suffice; if it is not good, then many are required. It is
necessary to smelt it in the crucible until the copper adhering to
the bar is
seen to be of a brassy colour, and if the upper as well as
the lower part of
the thin layer of copper may be easily broken, it
signifies that the copper
is perfectly melted; he places the point of
the bar on a small iron anvil,
and chips off the thin layer of copper
from it with a hammer.
If the copper is not good, the master draws off the “slags”
twice, or
three times if necessary—the first time when some of
the cakes have been
melted, the second when all have melted, the third
time when the copper has
been heated for some time. If the copper was of good quality, the “slags”
are not drawn
off before the operation is finished, but at the time they are to be
drawn off, he depresses the bar over both bellows, and places over both
a
stick, a cubit long and a palm wide, half cut away at the upper part,
so that it
may pass under the iron pin fixed at the back in the
perforated wood. This
he does likewise when the copper has been completely melted. Then the
assistant removes the iron plate with the tongs; these tongs
are four feet
three palms long, their jaws are about a foot in length,
and their straight part
measures two palms and three digits, and the
curved a palm and a digit. The same assistant, with the iron shovel, throws and heaps up the larger
pieces of charcoal into that part of the hearth which is against the
little wall
which protects the other wall from injury by fire, and
partly extinguishes
them by pouring water over them. The master, with a hazel stick inserted
Afterward he draws off the slags with a
rabble, which consists of an
iron blade, wide and sharp, and of alder-wood;
the blade is a digit and
a half in width and three feet long; the wooden handle
inserted in its
hollow part is the same number of feet long, and the alder-wood
in
which the blade is fixed must have the figure of a rhombus; it must be
three palms and a digit long, a palm and two digits wide, and a palm
thick. Subsequently he takes a broom and sweeps the charcoal dust and small coal
over the whole of the crucible, lest the copper should cool before it
flows
together; then, with a third rabble, he cuts off the slags which
may adhere
to the edge of the crucible. The blade of this rabble is two palms long and
a palm and one digit
wide, the iron part of the handle is a foot and three palms
long, the
wooden part six feet. Afterward he again draws off the slags
from the crucible, which the
assistant does not quench by pouring water
upon them, as the other
slags are usually quenched, but he sprinkles over
them a little water
and allows them to cool. If the copper should bubble,
he presses down the bubbles with the
rabble. Then he pours water on the wall
and the pipes, that it may flow down
warm into the crucible, for, the
copper, if cold water were to be
poured over it while still hot, would spatter
about. If a stone, or a piece of lute or wood, or a damp coal should then fall
into it, the crucible would vomit out all the copper with a loud noise
like
thunder, and whatever it touches it injures and sets on fire. Subsequently he
lays a curved board with a notch in it over the front
part of the crucible; it
is two feet long, a palm and two digits wide,
and a digit thick. Then
the copper in the crucible should be divided into cakes with an
iron wedge
shaped bar; this is three feet long, two digits wide,
and steeled on the end
for the distance of two digits, and its wooden
handle is three feet long. He
places this bar on the notched board, and, driving it into the
copper, moves
A—CRUCIBLE. B—BOARD. C—WEDGE-SHAPED BAR. D—CAKES OF
COPPER MADE BY
SEPARATING THEM WITH THE WEDGE-SHAPED BAR.
E—TONGS. F—TUB.
space in the copper, and he
separates the cake from the rest of the mass. If the copper is not perfectly smelted the cakes will be too thick, and
can
not be taken out of the crucible easily. Each cake is afterward seized by
the assistant with the tongs and
plunged into the water in the tub; the first
one is placed aside so
that the master may re-melt it again immediately, for,
since some
“slags” adhere to it, it is not as perfect as the subsequent
ones;
indeed, if the copper is not of good quality, he places the first
two cakes aside. Then, again pouring water over the wall and the pipes, he separates out the
second cake, which the assistant likewise immerses in water and places
on
the ground together with the others separated out in the same way,
which
he piles upon them. These, if the copper was of good quality, should be
thirteen or more in
number; if it was not of good quality, then fewer. If the
copper was of good quality, this part of the operation, which
indeed is dis
tributed into four parts, is accomplished by the
master in two hours; if of
mediocre quality, in two and a half hours;
if of bad quality, in three. The
“dried” cakes are re-melted, first in the first crucible
and then in the
second. The assistant must, as quickly as possible, quench all the cakes
with
water, after they have been cut out of the second crucible. Afterward
with the tongs he replaces in its proper place the iron plate
which was in front
of the furnace, and throws the charcoal back into
the crucible with a shovel. Meanwhile the master, continuing his work, removes the wooden stick from
the bars of the bellows, so that in re-melting the other cakes he may
accom
plish the third part of his process; this must be carefully
done, for if a particle
from any iron implement should by chance fall
into the crucible, or should
be thrown in by any malevolent person, the
copper could not be made until
the iron had been consumed, and
therefore double labour would have to be
expended upon it. Finally, the assistant extinguishes all the glowing coals,
and chips off
the dry lute from the mouth of the copper pipe with a hammer;
one end
of this hammer is pointed, the other round, and it has a wooden handle
five feet long. Because there is danger that the copper would be scattered if
the
upon them, should fall into the crucible, he
cleans them off in the meantime. Every week he takes the copper flowers out of the tub, after having poured
off
the water, for these fall into it from the cakes when they are
quenched.
The bellows which this master uses differ in size from the others, for the
boards are seven and a half feet long; the back part is three feet
wide;
the front, where the head is joined on is a foot, two palms and
as many digits. The head is a cubit and a digit long; the back part of it is a cubit and a
palm wide, and then becomes gradually narrower. The nozzles of the bellows
are bound together by means of an iron chain,
controlled by a thick
bar, one end of which penetrates into the ground
against the back of the long
wall, and the other end passes under the
beam which is laid upon the
foremost perforated beams. These nozzles are so placed in a copper pipe
that they are at a distance
of a palm from the mouth; the mouth should be
made three digits in
diameter, that the air may be violently expelled through
this narrow
aperture.
There now remain the liquation thorns, the ash-coloured copper, the
“slags,” and the
following
manner.
thorns, which have their origin from the cakes
of copper-lead alloy when
lead-silver is liquated, and as many parts of
a
derived from cakes made from once re-melted thorns by the
same method,
and to them are added a If there is in the works plenty of litharge, it
is substituted for the
de-silverized lead. One and a half
litharge and hearth-lead is added to the same
weight of primary thorns,
and half a
cakes composed of thorns twice re-melted by
the same method (tertiary
thorns), and a fourth part of a
one single liquation
cake is made from three In this manner
the smelter makes every day fifteen liquation cakes,
more or less; he takes
great care that the metallic substances, from
which the first liquation cake is
made, flow down properly and in due
order into the fore-hearth, before the
material of which the subsequent
cake is to be made. Five of these liquation
cakes are put simultaneously into the furnace in
which silver-lead is liquated
from copper, they weigh almost fourteen
made therefrom usually weigh quite a In all the liquation
cakes together there is usually one
in the silver-lead which drips from those cakes, and weighs seven
and a half In each of the
three
in
the two
is altogether one and a half
thorns, for in the thorns produced from
primary liquation cakes made of
copper and lead when silver-lead is
liquated from the copper, and those
produced in “drying”
the exhausted liquation cakes, there are almost two There are other thorns
besides, of which I will speak a little further
on.
Those in the Carpathian Mountains who make liquation cakes from the
copper “bottoms” which remain after the upper part of the
copper is
divided from the lower, in the furnace similar to an oven,
produce thorns when
the poor or mediocre silver-lead is liquated from
the copper. These, together
with those made of cakes of re-melted thorns, or made
with re-melted litharge,
are placed in a heap by themselves; but those
that are made from cakes
melted from hearth-lead are placed in a heap
separate from the first, and
likewise those produced from
“drying” the exhausted liquation cakes are
placed
separately; from these thorns liquation cakes are made. From the
first heap they take the fourth part of a
the same amount, from the third a
added one and a half
hearth-lead, and from these, melted in the blast furnace, a liquation
cake is
made; each workman makes twenty such cakes every day. But of theirs
enough has been said for the present; I will return to
ours.
The ash-coloured copper
the “dried” cakes, used
some years ago to be mixed with the thorns produced
from liquation of
the copper-lead alloy, and contained in themselves, equally
with the
first, two
washed from the
accretions and the other material. The inhabitants of the
Carpathian Mountains melt this kind of copper in
furnaces in which are re
melted the “slags” which flow
out when the copper is refined; but as this
soon melts and flows down
out of the furnace, two workmen are required for
thick
cakes from the forehearth. These cakes are only “dried,” and from
the
“dried” cakes copper is again made.
The “slags”
been drawn off from the
alloyed metals with a rabble, or whether they adhered
to the forehearth
to the thickness of a digit and made it smaller and
were taken off with
spatulas. In this manner two or three liquation cakes
are made, and afterward much
or little of the “slag,” skimmed from the
molten alloy of
copper and lead, is re-melted. Such liquation cakes should
weigh up to three
silver. Five cakes are placed at the same time in the furnace in which
argentiferous lead is liquated from copper, and from these are made
lead
which contains half an The exhausted
liquation cakes are laid upon the other baser exhausted
liquation cakes, from
both of which yellow copper is made. The base thorns thus obtained are
re-melted with a few baser
“slags,” after having been sprinkled with con
centrates
from furnace accretions and other material, and in this manner six
or
seven liquation cakes are made, each of which weighs some two
pondia. Five of these are placed at the same time in the furnace in which
silver-lead is liquated from copper; these drip three
lead,
each of which contains half an The basest thorns
thus produced should be re-melted with only a little
“slag.” The copper
alloyed with lead, which flows down from
the furnace into the fore
hearth, is poured out with a ladle into
oblong copper moulds; these cakes
are “dried” with base
exhausted liquation cakes. The thorns they produce
are added to the base thorns, and they are made
into cakes according to the
method I have described. From the “dried” cakes they make copper, of
which some add a
small portion to the best “dried” cakes when copper is
made
from them, in order that by mixing the base copper with the good it
may
be sold without loss. The “slags,” if they are utilisable, are re-melted
a second
and a third time, the cakes made from them are “dried,” and from
the “dried” cakes is made copper, which is mixed with the
good copper. The
“slags,” drawn off by the master who makes copper out of
“dried” cakes,
are sifted, and those which fall through the
sieve into a vessel placed under
neath are washed; those which
remain in it are emptied into a wheelbarrow
and wheeled away to the
blast furnaces, and they are re-melted together
with other
“slags,” over which are sprinkled the concentrates from washing
the slags or furnace accretions made at this time. The copper which flows out
oblong copper
moulds; in this way nine or ten cakes are made, which are
“dried,” together with bad exhausted liquation cakes, and
from these
“dried” cakes yellow
The
master, who makes copper from
“dried” cakes, draws off together with other
re-melted base
“slags”; for, indeed, if the copper cakes made from such
“slags” are broken, the fragments are called
copper is made For either two parts of
are mixed with one of yellow copper in the blast furnaces, and
melted; or, on
the contrary, two parts of yellow copper with one of
from
the furnace into the forehearth is poured out with a ladle into oblong
copper moulds heated beforehand. These moulds are sprinkled over with char
coal dust before the
dust is sprinkled over the copper when
it is poured in, lest the
yellow copper should freeze before they have
become well mixed. With a
piece of wood the assistant cleanses each cake from the dust,
when it is
turned out of the mould. Then he throws it into the tub containing hot water,
for the But as I have
so often made mention of the oblong copper moulds, I must
now speak of
them a little; they are a foot and a palm long, the inside
is three palms and a
digit wide at the top, and they are rounded at the
bottom.
The concentrates are of two kinds—precious and base.
obtained from the
accretions of the blast furnace, when liquation cakes are
made from
copper and lead, or from precious liquation thorns, or from the
better
quality “slags,” or from the best grade of concentrates, or from
the
sweepings and bricks of the furnaces in which exhausted liquation
cakes are
“dried”; all of these things are crushed and
washed, as I explained in Book
VIII. The base concentrates are made from accretions formed when cakes
are
cast from base thorns or from the worst quality of slags. The smelter
who makes liquation cakes from the precious concentrates,
adds to them
three wheelbarrowsful of litharge and four barrowsful of
hearth-lead and
one of ash-coloured copper, from all of which nine or
ten liquation cakes
are melted out, of which five at a time are placed
in the furnace in which
silver-lead is liquated from copper; a
from these cakes contains one The liquation thorns are
A—FURNACE. B—FOREHEARTH. C—OBLONG MOULDS.
placed apart
by themselves, of which one basketful is mixed with the precious
thorns
to be re-melted. The exhausted liquation cakes are “dried” at the
same time
as other good exhausted liquation cakes.
The thorns which are drawn off from the lead, when it is separated from
silver in the cupellation furnace
crucible in
the middle part of the furnaces, together with the hearth material
which has become defective and has absorbed silver-lead, are all melted
together with a little slag in the blast furnaces. The lead, or rather the
silver-lead, which flows from the furnace into
the fore-hearth, is poured out
into copper moulds such as are used by
the refiners; a
such lead contains four
contains more. A small portion of this material is added to the copper and
lead when
liquation cakes are made from them, if more were to be added
the alloy
would be much richer than it should be, for which reason the wise The
hearth-lead which remains in the middle of the crucible, and the
hearth
material which absorbs silver-lead, is mixed with other
hearth-lead which
remains in the cupellation furnace crucible; and yet
some cakes, made rich
in this manner, may be placed again in the
cupellation furnaces, together
with the rest of the silver-lead cakes
which the refiner has made.
The inhabitants of the Carpathian Mountains, if they have an abundance
of finely crushed copper
from the
furnace in which the exhausted liquation cakes are dried, or
litharge,
alloy them in various ways. The “first” alloy consists of two
from hearth-lead, and of half a
the furnace in which exhausted liquation cakes are
“dried,” and of copper
finished when he has made
forty liquation cakes of this kind. The
“second” alloy consists of two
quarter
a
The “third” alloy
consists of three
copper Liquation cakes are made from all these alloys; the
task of the
smelters is finished when they have made thirty cakes.
The process by which cakes are made among the Tyrolese, from which
they
separate the silver-lead, I have explained in Book IX.
Silver is separated from iron in the following manner.
Equal portions of
iron scales and filings and of
which, when covered with a lid and sealed, is placed in a
furnace, into
which air is blown. When this has melted and again cooled, the crucible
is broken; the
button that settles in the bottom of it, when taken out,
is pounded to
powder, and the same weight of lead being added, is mixed
and melted in
a second crucible; at last this button is placed in a cupel
and the
lead is separated from the silver.
There are a great variety of methods by which one metal is separated
from other metals, and the manner in which the same are alloyed I have
explained partly in the eighth book of
explain
elsewhere. Now I will proceed to the remainder of my subject.
END OF BOOK XI.
Previously I have dealt with the methods of
separating silver from
copper. There now remains
the portion which treats of solidified juices; and
whereas they might be considered as alien to things
metallic,
nevertheless, the reasons why they should
not be separated from it I
have explained in the
second book.
Solidified juices are either prepared from waters
in which nature or art
has infused them, or they are
produced from the liquid juices
themselves, or from stony minerals. Sagacious
people, at first observing the waters of some lakes to be
naturally full of juices
which thickened on being dried up by the heat
of the sun and thus became
solidified juices, drew such waters into
other places, or diverted them
into low-lying places adjoining hills,
so that the heat of the sun should
likewise cause them to condense. Subsequently, because they observed that
in this wise the solidified
juices could be made only in summer, and then
not in all countries, but
only in hot and temperate regions in which it seldom
rains in summer,
they boiled them in vessels over a fire until they began to
thicken. In this manner, at all times of the year, in all regions, even the
coldest, solidified juices could be obtained from solutions of such
juices,
whether made by nature or by art. Afterward, when they saw juices
drip from some roasted stones, they
cooked these in pots in order to obtain
solidified juices in this wise
also. It is worth the trouble to learn the pro
portions and the methods by
which these are made.
I will therefore begin with salt, which is made from water either salty
by nature, or by the labour of man, or else from a solution of salt, or
from lye, likewise salty. Water which is salty by nature, is condensed and
converted into salt in
salt-pits by the heat of the sun, or else by the heat
of a fire in pans
or pots or trenches. That which is made salty by
art, is also condensed by fire and changed
into salt. There should be as
many salt-pits dug as the circumstance of the place
permits, but there should
not be more made than can be used, although
we ought to make as much
salt as we can sell. The depth of salt-pits should be moderate, and the
bottom should be
level, so that all the water is evaporated from the salt by
the heat of
the sun. The salt-pits should first be encrusted with salt, so
that they may not
suck up the water. The method of pouring or leading
sea-water into salt-pits is very old,
and is still in use in many places. The
method is not less old, but less common, to pour well-water into
salt-pits, as
was done in Babylon, for which Pliny is the authority,
and in Cappadocia,
where they used not only well-water, but also
spring-water. In all hot
countries salt-water and lake-water are conducted, poured or
carried into
salt-pits, and, being dried by the heat of the sun, are
converted into
if they be flooded with great and frequent showers
of rain the evaporation is
hindered. If this happens rarely, the salt acquires a disagreeable
in this case the salt-pits
have to be filled with other sweet water.
Salt from sea-water is made in the following manner.
Near that part
of the seashore where there is a quiet pool, and there
are wide, level plains
which the inundations of the sea do not
overflow, three, four, five, or six
trenches are dug six feet wide,
twelve feet deep, and six hundred feet long,
or longer if the level
place extends for a longer distance; they are two hundred
feet distant
from one another; between these are three transverse trenches. Then are dug the principal pits, so that when the water has been raised from
the pool it can flow into the trenches, and from thence into the
salt-pits,
of which there are numbers on the level ground between the
trenches. The
salt-pits are basins dug to a moderate depth; these are banked round
with
the earth which was dug in sinking them or in cleansing them, so
that between
the basins, earth walls are made a foot high, which retain
the water let into
them. The trenches have openings, through which the first basins receive
the
water; these basins also have openings, through which the water flows
again from one into the other. There should be a slight fall, so that the
water may flow from one basin
into the other, and can thus be replenished. All these things having been done rightly and in order, the gate is raised
that
opens the mouth of the pool which contains sea-water mixed with
rain-water
or river-water; and thus all of the trenches are filled. Then the gates of the
first basins are opened, and thus the remaining
basins are filled with the
water from the first; when this salt-water
condenses, all these basins are
incrusted, and thus made clean from
earthy matter. Then again the first
basins are filled up from the nearest trench with
the same kind of water,
and left until much of the thin liquid is
converted into vapour by the heat
of the sun and dissipated, and the
remainder is considerably thickened. Then
their gates being opened, the water passes into the second basins;
and
when it has remained there for a certain space of time the gates
are opened,
so that it flows into the third basins, where it is all
condensed into salt. After the salt has been taken out, the basins are filled again and again with
sea-water. The salt is raked up with wooden rakes and thrown out with
shovels.
Salt-water is also boiled in pans, placed in sheds near the wells from
which it is drawn. Each shed is usually named from some animal or other
thing which is
pictured on a tablet nailed to it. The walls of these sheds
are made either from baked earth or from wicker
work covered with thick
A—SEA. B—POOL. C—GATE. D—TRENCHES. E—SALT
BASINS. F—RAKE.
G—SHOVEL.When of brick they
are often sixteen feet high, and if the roof rises
twenty-four feet high, then
the walls which are at the ends must be
made forty feet high, as likewise
the interior partition walls. The roof consists of large shingles four feet long,
one foot wide, and
two digits thick; these are fixed on long narrow planks
placed on the
rafters, which are joined at the upper end and slope in opposite
directions. The whole of the under side is plastered one digit thick with
straw
mixed with lute; likewise the roof on the outside is plastered one
and
a half feet thick with straw mixed with lute, in order that the shed
should not run any risk of fire, and that it should be proof against
rain, and
be able to retain the heat necessary for drying the lumps of
salt. Each shed
is divided into three parts, in the first of which the
firewood and straw are
placed; in the middle room, separated from the
first room by a partition, is
the fireplace on which is placed the
caldron. To the right of the caldron is
a tub, into which is emptied the brine
brought into the shed by the porters;
to the left is a bench, on which
there is room to lay thirty pieces of salt. In the third room, which is in the back part of the house, there is made a
pile
of clay or ashes eight feet higher than the floor, being the same
height as the
bench. The master and his assistants, when they carry away the lumps of
salt
from the caldrons, go from the former to the latter. They ascend from
the right side of the caldron, not by steps, but by a
slope of earth. At the
top of the end wall are two small windows, and a third is in the
roof, through
which the smoke escapes. This smoke, emitted from both the back and the
front of the furnace,
finds outlet through a hood through which it makes
its way up to the
windows; this hood consists of boards projecting one
beyond the other,
which are supported by two small beams of the roof. Opposite the fireplace the middle partition has an open door eight feet high
and four feet wide, through which there is a gentle draught which
drives the
smoke into the last room; the front wall also has a door of
the same height
and width. Both of these doors are large enough to permit the firewood or
straw or
the brine to be carried in, and the lumps of salt to be carried out;
these doors must be closed when the wind blows, so that the boiling
will
not be hindered. Indeed, glass panes which exclude the wind but transmit the
light,
should be inserted in the windows in the walls.
They construct the greater part of the fireplace of rock-salt and of clay
mixed with salt and moistened with brine, for such walls are greatly
hardened by the fire. These fireplaces are made eight and a half feet long,
seven and three
quarters feet wide, and, if wood is burned in them, nearly
four feet
high; but if straw is burned in them, they are six feet high. An
iron rod, about four feet long, is engaged in a hole in an iron foot,
which
stands on the base of the middle of the furnace mouth. This mouth is three
feet in width, and has a door which opens inward;
through it they throw
in the straw.
The caldrons are rectangular, eight feet long, seven feet wide, and half a
foot high, and are made of sheets of iron or lead, three feet long and
of the
same width, all but two digits. These plates are not very thick, so that the
A—SHED. B—PAINTED SIGNS. C—FIRST ROOM. D—MIDDLE ROOM.
E—THIRD
ROOM. F—TWO LITTLE WINDOWS IN THE END WALL.
G—THIRD LITTLE WINDOW IN THE
ROOF. H—WELL. I—WELL OF
ANOTHER KIND. K—CASK. L—POLE. M—FORKED
STICKS IN
WHICH THE PORTERS REST THE POLE WHEN THEY ARE TIRED.The
more salty the water is, the sooner it is condensed into salt. To prevent
the brine from leaking out at the points where the metal
plates are fastened
with rivets, the caldrons are smeared over with a
cement made of ox-liver
and ox-blood mixed with ashes. On each side of the middle of the furnace
two rectangular posts, three
feet long, and half a foot thick and wide are
set into the ground, so
that they are distant from each other only one and
a half feet. Each of them rises one and a half feet above the caldron.
After
the caldron has been placed on the walls of the furnace, two beams
of the
same width and thickness as the posts, but four feet long, are
laid on these
posts, and are mortised in so that they shall not fall. There rest trans
versely upon these beams three bars, three feet
long, three digits wide, and
two digits thick, distant from one another
one foot. On each of these hang
three iron hooks, two beyond the beams and one in
the middle; these are a
foot long, and are hooked at both ends, one
hook turning to the right, the other
to the left. The bottom hook catches in the eye of a staple, whose ends are
fixed in
the bottom of the caldron, and the eye projects from it. There are
besides, two longer bars six feet long, one palm wide, and
three digits thick,
which pass under the front beam and rest upon the
rear beam. At the rear end
of each of the bars there is an iron hook two feet and
three digits long, the
lower end of which is bent so as to support the
caldron. The rear end of the
caldron does not rest on the two rear corners of the
fireplace, but is distant
from the fireplace two thirds of a foot, so
that the flame and smoke can escape;
this rear end of the fireplace is
half a foot thick and half a foot higher than
the caldron. This is also the thickness and height of the wall between the
caldron
and the third room of the shed, to which it is adjacent. This back
wall is made of clay and ashes, unlike the others which are
made of rock-salt. The caldron rests on the two front corners and sides of the fireplace, and is
cemented with ashes, so that the flames shall not escape. If a dipperful
of brine poured into the caldron should flow into all the
corners, the caldron
is rightly set upon the fireplace.
The wooden dipper holds ten Roman
dippers fullThe brine drawn up from the well is poured into such casks
and carried
by porters, as I have said before, into the shed and poured into a
tub,
and in those places where the brine is very strong it is at once
trans
ferred with the dippers into the caldron. That brine which is less strong is
thrown into a small tub with a deep
ladle, the spoon and handle of which
are hewn out of one piece of wood. In this tub rock-salt is placed in order
A—FIREPLACE. B—MOUTH OF FIREPLACE. C—CALDRON. D—POSTS
SUNK INTO THE
GROUND. E—CROSS-BEAMS. F—SHORTER BARS.
G—IRON HOOKS. H—STAPLES.
I—LONGER BARS. K—IRON
ROD BENT TO SUPPORT THE CALDRON.
launder which leads
into the caldron. From thirty-seven dippersful of brine
the master or his deputy, at Halle
in Saxony,
of salt. Each master has a helper, or in the place of a helper his wife assists
him in his work, and, in addition, a youth who throws wood or straw
under
the caldron. He, on account of the great heat of the workshop, wears
a straw cap on
his head and a breech cloth, being otherwise quite naked. As soon as the master has poured the first dipperful of brine into the
caldron
the youth sets fire to the wood and straw laid under it. If the firewood is
bundles of faggots or brushwood, the salt will be
white, but if straw is burned,
then it is not infrequently blackish,
for the sparks, which are drawn up with
the smoke into the hood, fall
down again into the water and colour it black.
In order to accelerate the condensation of the brine, when the master
has poured in two casks and as many dippersful of brine, he adds about
a
Roman
blood, or else
he mixes it into the nineteenth dipperful of brine, in order that
it
may be dissolved and distributed into all the corners of the caldron; in
other
places the blood is dissolved in beer. When the boiling water seems to be
mixed with scum, he skims it with a
ladle; this scum, if he be working with
rock-salt, he throws into the
opening in the furnace through which the smoke
escapes, and it is dried
into rock-salt; if it be not from rock-salt, he pours
it on to the
floor of the workshop. From the beginning to the boiling and
skimming is the work of
half-an-hour; after this it boils down for another
quarter-of-an-hour,
after which time it begins to condense into salt. When
it begins to thicken with the heat, he and his helper stir it
assiduously with a
wooden spatula, and then he allows it to boil for an
hour. After this he pours
in a In order that the wind should not blow
into the caldron, the helper
covers the front with a board seven and a half
feet long and one foot
high, and covers each of the sides with boards three and
three quarters
feet long. In order that the front board may hold more
firmly, it is fitted into
the caldron itself, and the sideboards are fixed on the
front board and
upon the transverse beam. Afterward, when the boards
have been lifted off, the helper places two
baskets, two feet high and as many
wide at the top, and a palm wide at
the bottom, on the transverse beams,
and into them the master throws
the salt with a shovel, taking half-an-hour
to fill them. Then, replacing the boards on the caldron, he allows the brine
to boil
for three quarters of an hour. Afterward the salt has again to be
removed with a shovel, and when the
baskets are full, they pile up the salt in
heaps.
In different localities the salt is moulded into different shapes.
In the
baskets the salt assumes the form of a cone; it is not moulded in
baskets
alone, but also in moulds into which they throw the salt, which
are made in
A—WOODEN DIPPER. B—CASK. C—TUB. D—MASTER.
E—YOUTH. F—WIFE.
G—WOODEN SPADE. H—BOARDS.
I—BASKETS. K—HOE. L—RAKE. M—STRAW.
N—BOWL. O—BUCKET CONTAINING THE BLOOD. P—TANKARD
WHICH CONTAINS BEER.These tablets and
cones are kept in the higher part of the third room of
the house, or else on
the flat bench of the same height, in order that
they may dry better in the
warm air. In the manner I have described, a master and his helper continue
one
after the other, alternately boiling the brine and moulding the salt,
day and night, with the exception only of the annual feast days. No caldron
is able to stand the fire for more than half a year. The master pours in water
and washes it out every week; when it is
washed out he puts straw under
it and pounds it; new caldrons he washes
three times in the first two
weeks, and afterward twice. In this manner the incrustations fall from
the bottom; if they are not
cleared off, the salt would have to be made
more slowly over a fiercer
fire, which requires more brine and burns the
plates of the caldron. If any cracks make their appearance in the caldron
they are filled up
with cement. The salt made during the first two weeks is
not so good, being usually
stained by the rust at the bottom where incrusta
tions have not yet
adhered.
Although salt made in this manner is prepared only from the brine of
A—POOL. B—POTS. C—LADLE. D—PANS. E—TONGS.
river-, lake-, and sea-water, and also of those
waters which are artificially
salted. For in places where rock-salt is dug, the impure and the broken pieces
are thrown into fresh water, which, when boiled, condenses into salt. Some,
indeed, boil sea-salt in fresh water again, and mould the salt
into the little
cones and other shapes.
Some people make salt by another method, from salt water which
flows
from hot springs that issue boiling from the earth. They set earthen
ware pots in a pool of the spring-water, and into
them they pour water scooped
up with ladles from the hot spring until
they are half full. The perpetual
heat of the waters of the pool evaporates the salt water
just as the heat of
the fire does in the caldrons. As soon as it begins to thicken, which happens
when it has been reduced
by boiling to a third or more, they seize the pots
with tongs and pour
the contents into small rectangular iron pans, which have
also been
placed in the pool. The interior of these pans is usually three feet
long, two feet wide,
and three digits deep, and they stand on four heavy legs,
so that the
water flows freely all round, but not into them. Since the water
flows continuously from the pool through the little
canals, and the spring
A—POTS. B—TRIPOD. C—DEEP LADLE.
the
thickened water poured into the pans into salt; this is at once taken
out with shovels, and then the work begins all over again. If the salty water
contains other juices, as is usually the case with
hot springs, no salt should
be made from them.
Others boil salt water, and especially sea-water, in large iron pots;
this salt is blackish, for in most cases they burn straw under them. Some
people boil in these pots the brine in which fish is pickled. The salt which
they make tastes and smells of fish.
A—TRENCH. B—VAT INTO WHICH THE SALT WATER FLOWS. C—LADLE.
D—SMALL
BUCKET WITH POLE FASTENED INTO IT.
Those who make salt by pouring brine over firewood, lay the wood in
trenches which are twelve feet long, seven feet wide, and two and one
half
feet deep, so that the water poured in should not flow out. These trenches
are constructed of rock-salt wherever it is to be had, in
order that they should
not soak up the water, and so that the earth
should not fall in on the front,
back and sides. As the charcoal is turned into salt at the same time as the
A—LARGE VAT. B—PLUG. C—SMALL TUB. D—DEEP LADLE.
E—SMALL VAT.
F—CALDRON.
into salt. Oak is the best wood, as its pure ash yields salt; elsewhere
hazel
wood is lauded. But with whatever wood it be made, this salt is not
greatly appreciated,
being black and not quite pure; on that account this
method of
salt-making is disdained by the Germans and Spaniards.
The solutions from which salt is made are prepared from salty earth or
from earth rich in salt and saltpetre. Lye is made from the ashes of reeds
and rushes. The solution obtained from salty earth by boiling, makes salt
only; from
the other, of which I will speak more a little later, salt and
salt
petre are made; and from ashes is derived lye, from which its
own salt is
obtained. The ashes, as well as the earth, should first be put into a large
vat;
then fresh water should be poured over the ashes or earth, and it should
be stirred for about twelve hours with a stick, so that it may dissolve
the
salt. Then the plug is pulled out of the large vat; the solution of salt or the
lye is drained into a small tub and emptied with ladles into small
vats;
finally, such a solution is transferred into iron or lead
caldrons and boiled,
until the water having evaporated, the juices are
condensed into salt. The
above are the various methods for making salt. (Illustration p. 557.)
lye. In the same manner as sea-water or salt-water is poured into salt-pits
and evaporated by the heat of the sun and changed into salt, so the
Nile
is led into
A—NILE. B—NITRUM-PITS, SUCH AS I CONJECTURE THEM TO BE.
verted into Just as the sea, in flowing of its own will over the soil
of this same
Egypt, is changed into salt, so also the Nile, when it overflows
in the
dog days, is converted into The solution from which
percolating through
fresh water percolating through ashes of oak
or hard oak. Both solutions
are taken out of vats and poured into rectangular copper
caldrons, and are
boiled until at last they condense into
Native as well as manufactured
and boiled in the same
caldrons; the decoction is poured into vats in which
are copper wires,
and, adhering to them, it hardens and becomes
which the Moors call Formerly
Cyprian verdigris, and ground with Cyprian copper in
Cyprian mortars, as
Pliny writes. Some
A—VAT IN WHICH THE SODA IS MIXED. B—CALDRON. C—TUB IN WHICH
CONDENSED. D—COPPER WIRES. E—MORTAR.
Saltpetre
tained for a while in the
mouth, has an acrid and salty taste. This earth,
together with a powder, are alternately put into a vat in
layers a palm deep. The powder consists of two parts of unslaked lime and three parts of ashes of
oak, or holmoak, or Italian oak, or Turkey oak, or of some similar
kind. Each
vat is filled with alternate layers of these to within
three-quarters of a foot
of the top, and then water is poured in until
it is full. As the water percolates
through the material it dissolves the saltpetre;
then, the plug being pulled
out from the vat, the solution is drained
into a tub and ladled out into small If when tested it tastes very salty, and at the same time acrid, it is
good; but, if not, then it is condemned, and it must be made to
percolate
again through the same material or through a fresh lot. Even two or three
waters may be made to percolate through the same earth
and become full
of saltpetre, but the solutions thus obtained must not
be mixed together
unless all have the same taste, which rarely or never
happens. The first of
these solutions is poured into the first vat, the next into
the second, the third
into the third vat; the second and third
solutions are used instead of plain
water to percolate through fresh
material; the first solution is made in
this manner from both the
second and third. As soon as there is an abun
dance of this solution it is poured into
the rectangular copper caldron and
evaporated to one half by boiling;
then it is transferred into a vat covered
with a lid, in which the
earthy matter settles to the bottom. When the
solution is clear it is poured back into the same pan, or into
another, and
re-boiled. When it bubbles and forms a scum, in order that it should
not run over
and that it may be greatly purified, there is poured into it three
or
four pounds of lye, made from three parts of oak or similar ash and one of
unslaked lime. But in the water, prior to its being poured in, is dissolved
rock
alum, in the proportion of one hundred and twenty Shortly afterward the solution will be found to be clear
and blue. It is boiled until the waters, which are easily volatile (
evaporated, and then the greater part of the salt, after it has settled
at the
bottom of the pan, is taken out with iron ladles. Then the concentrated
solution is transferred to the vat in which rods
are placed horizontally and
vertically, to which it adheres when cold,
and if there be much, it is condensed
in three or four days into
saltpetre. Then the solution which has not con
gealed, is poured out and put on
one side or re-boiled. The saltpetre being
cut out and washed with its own solution, is thrown
on to boards that it may
drain and dry. The yield of saltpetre will be much or little in proportion
to whether
the solution has absorbed much or little; when the saltpetre
has been
obtained from lye, which purifies itself, it is somewhat clear and
pure.
The purest and most transparent, because free from salt, is made if it is
drawn off at the thickening stage, according to the following method. There
A—CALDRON. B—LARGE VAT INTO WHICH SAND IS THROWN. C—PLUG.
D—TUB.
E—VAT CONTAINING THE RODS.
is thrown as
much of the already made saltpetre as the solution and lye will
dissolve. As soon as the mixture effervesces and forms scum, it is
trans
ferred to a vat, into which on a cloth has been thrown washed
sand obtained
from a river. Soon afterward the plug is drawn out of the hole at the
bottom, and the
mixture, having percolated through the sand, escapes into
a tub. It is then reduced by boiling in one or another of the caldrons, until
the greater part of the solution has evaporated; but as soon as it is
well
boiled and forms scum, a little lye is poured into it. Then it is transferred to
another vat in which there are small rods, to
which it adheres and congeals in
two days if there is but little of it,
or if there is much in three days, or
at the most in four days; if it
does not condense, it is poured back into the
caldron and re-boiled
down to half; then it is transferred to the vat to cool. The process must be repeated as often as is necessary.
Others refine saltpetre by another method, for with it they fill a pot
made of copper, and, covering it with a copper lid, set it over live
coals, where
it is heated until it melts. They do not cement down the lid, but it has
a handle, and can be lifted
for them to see whether or not the melting has taken
place. When it has melted, powdered sulphur is sprinkled in, and if the pot
set
on the fire does not light it, the sulphur kindles, whereby the thick,
greasy
matter floating on the saltpetre burns up, and when it is
consumed the salt
petre is pure. Soon afterward the pot is removed from the fire, and later, when
cold,
the purest saltpetre is taken out, which has the appearance of white
marble, the earthy residue then remains at the bottom. The earths from
which the solution was made, together with branches of
oak or similar trees,
are exposed under the open sky and sprinkled with
water containing saltpetre. After remaining thus for five or six years, they are again ready to be made
into a solution.
Pure saltpetre which has rested many years in the earth, and that which
exudes from the stone walls of wine cellars and dark places, is mixed
with the
first solution and evaporated by boiling.
Thus far I have described the methods of making
less
varied or multifarious than those for making salt. Now I propose to
describe the methods of making alum,
nor simple, because it is made from boiling aluminous water until it
con
denses to alum, or else from boiling a solution of alum which
is obtained
from a kind of earth, or from rocks, or from pyrites, or
other minerals.
This kind of earth having first been dug up in such quantity as would
make three hundred wheelbarrow loads, is thrown into two tanks; then
the
water is turned into them, and if it (the earth) contains vitriol
it must be
diluted with urine. The workmen must many times a day stir the
ore with long, thick sticks
in order that the water and urine may be
mixed with it; then the plugs
having been taken out of both tanks, the
solution is drawn off into a
trough, which is carved out of one or two trees. If the locality is supplied with an abundance of such ore, it should not
immediately be thrown into the tanks, but first conveyed into open
spaces
and heaped up, for the longer it is exposed to the air and the
rain, the better it
is; after some months, during which the ore has
been heaped up in open
spaces into mounds, there are generated veinlets
of far better quality than
the ore. Then it is conveyed into six or more tanks, nine feet in length
and
breadth and five in depth, and afterward water is drawn into them
of
similar solution. After this, when the water has absorbed the alum, the
plugs are pulled
out, and the solution escapes into a round reservoir forty
feet wide
and three feet deep. Then the ore is thrown out of the tanks
into other tanks, and water
again being run into the latter and the urine
added and stirred by
means of poles, the plugs are withdrawn and
the solution is run off
into the same reservoir. A few days afterward,
the reservoirs containing the solution are emptied
through a small launder,
and run into rectangular lead caldrons; it is
boiled in them until the The earthy sediment deposited
at the bottom of the caldron is composed
of fatty and aluminous matter, which
usually consists of small
incrustations, in which there is not infrequently found
a very white
and very light powder of asbestos or gypsum. The solution now
seems to be full of meal. Some people instead pour the partly evaporated
solution into a vat, so
that it may become pure and clear; then pouring it
back into the
caldron, they boil it again until it becomes mealy. By which
ever process it has been condensed, it is then poured into
a wooden tub
sunk into the earth in order to cool it. When it becomes cold it is poured
into vats, in which are arranged
horizontal and vertical twigs, to which the
alum clings when it
condenses; and thus are made the small white trans
parent cubes,
which are laid to dry in hot rooms.
If vitriol forms part of the aluminous ore, the material is dissolved in
water without being mixed with urine, but it is necessary to pour that
into
the clear and pure solution when it is to be re-boiled. This separates the
vitriol from the alum, for by this method the latter
sinks to the bottom of the
caldron, while the former floats on the top;
both must be poured separately
into smaller vessels, and from these
into vats to condense. If, however, when
the solution was re-boiled they did not separate, then
they must be poured
from the smaller vessels into larger vessels and
covered over; then the vitriol
separating from the alum, it condenses. Both are cut out and put to dry in
the hot room, and are ready to be
sold; the solution which did not congeal in
A—TANKS. B—STIRRING POLES. C—PLUG. D—TROUGH.
E—RESERVOIR. F—LAUNDER.
G—LEAD CALDRON.
H—WOODEN TUBS SUNK INTO THE EARTH. I—VATS IN WHICH
TWIGS
ARE FIXED.The earth which settled at the bottom of the caldron is carried back to the
tanks, and, together with the ore, is again dissolved with water and
urine. The earth which remains in the tanks after the solution has been drawn off
is emptied in a heap, and daily becomes more and more aluminous in the
same way as the earth from which saltpetre was made, but fuller of its
juices,
wherefore it is again thrown into the tanks and percolated by
water.
Aluminous rock is first roasted in a furnace similar to a lime kiln.
At
the bottom of the kiln a vaulted fireplace is made of the same kind
of rock;
the remainder of the empty part of the kiln is then entirely
filled with the
same aluminous rocks. Then they are heated with fire until they are red
hot and have exhaled
their sulphurous fumes, which occurs, according to their
divers nature,
within the space of ten, eleven, twelve, or more hours. One
thing the master must guard against most of all is not to roast the
rock
either too much or too little, for on the one hand they would not
soften when
sprinkled with water, and on the other they either would be
too hard or
would crumble into ashes; from neither would much alum be
obtained, for
the strength which they have would be decreased. When the rocks are cooled
they are drawn out and conveyed into an open
space, where they are piled one
upon the other in heaps fifty feet
long, eight feet wide, and four feet high,
which are sprinkled for
forty days with water carried in deep ladles. In
spring the sprinkling is done both morning and evening, and in summer
at After being moistened for this length of time the rocks begin
to fall to
pieces like slaked lime, and there originates a certain new material
of
the future alum, which is soft and similar to the
in the rocks. It is white if the stone was white before it was roasted, and
rose-coloured if red was mixed with the white; from the former, white
alum is obtained, and from the latter, rose-coloured. A round furnace is
made, the lower part of which, in order to be able to
endure the force of
the heat, is made of rock that neither melts nor
crumbles to powder by the
fire. It is constructed in the form of a basket, the walls of which are two
feet high, made of the same rock. On these walls rests a large round caldron
made of copper plates, which
is concave at the bottom, where it is eight feet
in diameter. In the empty space under the bottom they place the wood to be
kindled
with fire. Around the edge of the bottom of the caldron, rock
is built in
cone-shaped, and the diameter of the bottom of the rock structure
is
seven feet, and of the top ten feet; it is eight feet deep. The inside,
after being rubbed over with oil, is covered with cement, so
that it may be
able to hold boiling water; the cement is composed of
fresh lime, of
which the lumps are slaked with wine, of iron-scales,
and of sea-snails,
ground and mixed with the white of eggs and oil. The edges of the caldron
are surmounted with a circle of wood a foot
thick and half a foot high,
on which the workmen rest the wooden
shovels with which they cleanse
the water of earth and of the
undissolved lumps of rock that remain at The caldron, being thus prepared, is entirely
filled through a launder
with water, and this is boiled with a fierce fire
until it bubbles. Then little by little eight wheelbarrow loads of the
material, composed
of roasted rock moistened with water, are gradually
emptied into the
caldron by four workmen, who, with their shovels which
reach to the
bottom, keep the material stirred and mixed with water, and
by the same
means they lift the lumps of undissolved rock out of the
caldron. In this manner the material is thrown in, in three or four lots, at
intervals of two or three hours more or less; during these intervals,
the
water, which has been cooled by the rock and material, again begins
to boil. The water, when sufficiently purified and ready to congeal, is ladled out and
run off with launders into thirty troughs. These troughs are made of oak,
holm oak, or Turkey oak; their interior
is six feet long, five feet deep, and
four feet wide. In these the water congeals and condenses into alum, in the
spring in
the space of four days, and in summer in six days. Afterward the
holes at the bottom of the oak troughs being opened, the
water which has
not congealed is drawn off into buckets and poured back
into the caldron;
or it may be preserved in empty troughs, so that the
master of the workmen,
having seen it, may order his helpers to pour it
into the caldron, for the water
which is not altogether wanting in
alum, is considered better than that which
has none at all. Then the alum is hewn out with a knife or a chisel.
It is
thick and excellent according to the strength of the rock, either
white or
pink according to the colour of the rock. The earthy powder, which remains
three to four digits thick as the
residue of the alum at the bottom of the
trough is again thrown into
the caldron and boiled with fresh aluminous
material. Lastly, the alum cut out is washed, and dried, and sold.
Alum is also made from crude pyrites and other aluminous mixtures.
It is first roasted in an enclosed area: then, after being exposed for some
A—FURNACE. B—ENCLOSED SPACE. C—ALUMINOUS ROCK. D—DEEP
LADLE.
E—CALDRON. F—LAUNDER. G—TROUGHS.After this the solution is poured into the leaden rectangular pans and boiled
until it condenses into alum. The pyrites and other stones which are not
mixed with alum alone, but
which also contain vitriol, as is most usually the
case, are both
treated in the manner which I have already described. Finally,
if metal is contained in the pyrites and other rock, this
material must be dried,
and from it either gold, silver, or copper is
made in a furnace.
Vitriol
sory
vitriol.
The vitriol water is collected into pools, and if it cannot be drained into
them, it must be drawn up and carried to them in buckets by a workman.
A—TUNNEL. B—BUCKET. C—PIT.
In hot regions or in summer,
it is poured into out-of-door pits which have
been dug to a certain
depth, or else it is extracted from shafts by pumps
and poured into
launders, through which it flows into the pits, where it is
condensed
by the heat of the sun. In cold regions and in winter these vitriol
waters are boiled down with
equal parts of fresh water in rectangular leaden
caldrons; then, when
cold, the mixture is poured into vats or into tanks,
which Pliny calls
wooden fish-tanks. In these tanks light cross-beams are
fixed to the upper part, so that
they may be stationary, and from them hang
ropes stretched with little
stones; to these the contents of the thickened
solutions congeal and
adhere in transparent cubes or seeds of vitriol, like
bunches of
grapes.
A—CALDRON. B—TANK. C—CROSS-BARS. D—ROPES.
E—LITTLE STONES.
By the third method vitriol is made out of
If
the mines give an abundant supply of
reject the
particularly from the These materials having been dug and thrown
into the tanks, they are
first dissolved with water; then, in order to recover
the pyrites from
which copper is not rarely smelted and which forms a sedi
ment at
the bottom of the tanks, the solution is transferred to other vats,
which are nine feet wide and three feet deep. Twigs and wood which float
on the surface are lifted out with a broom
made of twigs, and afterward all the
sediment settles at the bottom of
this vat. The solution is poured into a
rectangular leaden caldron eight feet
long, three feet wide, and the same in
depth. In this caldron it is boiled until it becomes thick and viscous, when
it
is poured into a launder, through which it runs into another leaden caldron
of the same size as the one described before. When cold, the solution is
drawn off through twelve little launders, out
of which it flows into as many
wooden tubs four and a half feet deep
and three feet wide. Upon these tubs
are placed perforated crossbars distant from each other
from four to six
digits, and from the holes hang thin laths, which
reach to the bottom, with The vitriol adheres to these laths, and
within the space of a few days
congeals into cubes, which are taken away
and put into a chamber having
a sloping board floor, so that the moisture
which drips from the
vitriol may flow into a tub beneath. This solution is
re-boiled, as is also that solution which was left in
the twelve tubs, for, by
reason of its having become too thin and
liquid, it did not congeal, and was
thus not converted into
vitriol.
A—WOODEN TUB. B—CROSS-BARS. C—LATHS. D—SLOPING FLOOR
OF THE CHAMBER.
E—TUB PLACED UNDER IT.
The fourth method of making vitriol is from vitriolous earth or stones.
Such ore is at first carried and heaped up, and is then left for five or six
months
exposed to the rain of spring and autumn, to the heat of summer,
and to the
rime and frost of winter. It must be turned over several times with shovels,
so that the part at
the bottom may be brought to the top, and it is thus
ventilated and
cooled; by this means the earth crumbles up and loosens,
and the stone
changes from hard to soft. Then the ore is covered with a roof,
or else it is taken away and placed
under a roof, and remains in that place
six, seven, or eight months. Afterward as large a portion as is required is
thrown into a vat, which
is half-filled with water; this vat is one hundred It has an opening at the
bottom, so that when it is opened the dregs of
the ore from which the vitriol
comes may be drawn off, and it has, at
the height of one foot from the bottom,
three or four little holes, so
that, when closed, the water may be retained,
and when opened the
solution flows out. Thus the ore is mixed with water,
stirred with poles and left in the
tank until the earthy portions sink to the
bottom and the water absorbs
the juices. Then the little holes are opened,
the solution flows out of the vat, and
is caught in a vat below it; this vat is
of the same length as the
other, but twelve feet wide and four feet deep. If
the solution is not sufficiently vitriolous it is mixed with fresh
ore; but if it
contains enough vitriol, and yet has not exhausted all
of the ore rich in vitriol,
it is well to dissolve the ore again with
fresh water. As soon as the solution
becomes clear, it is poured into the rectangular
leaden caldron through
launders, and is boiled until the water is
evaporated. Afterward as many thin
strips of iron as the nature of the solution
requires, are thrown in, and then
it is boiled again until it is thick
enough, when cold, to congeal into vitriol. Then it is poured into tanks or vats, or any other receptacle, in which all
of it
that is apt to congeal does so within two or three days. The solution which
does not congeal is either poured back into the
caldron to be boiled again, or
A—CALDRON. B—MOULDS. C—CAKES
The solidified vitriol is hewn out, and having once more been thrown into the
caldron, is re-heated until it liquefies; when liquid, it is poured
into
moulds that it may be made into cakes. If the solution first poured out is
not satisfactorily thickened, it is
condensed two or three times, and each
time liquefied in the caldron
and re-poured into the moulds, in which
manner pure cakes, beautiful to
look at, are made from it.
The vitriolous pyrites, which are to be numbered among the mixtures
(
the
solution is boiled in leaden caldrons until it condenses into vitriol. Both
alum and vitriol are often made out of these, and it is no wonder,
for these
juices are cognate, and only differ in the one
point,—that the former is less, the
latter more, earthy. That pyrites which contains metal must be smelted in the
furnace. In the same manner, from other mixtures of vitriolic and
metallifer
ous material are made vitriol and metal. Indeed, if ores of vitriolous pyrites
abound, the miners split small
logs down the centre and cut them off in lengths
as long as the drifts
and tunnels are wide, in which they lay them down trans
versely;
but, that they may be stable, they are laid on the ground with the wide
side down and the round side up, and they touch each other at the
bottom,
but not at the top. The intermediate space is filled with pyrites, and the same
crushed are
scattered over the wood, so that, coming in or going out, the
road is
flat and even. Since the drifts or tunnels drip with water, these
pyrites are soaked,
and from them are freed the vitriol and cognate things. If
the water ceases to drip, these dry and harden, and then they are
raised
from the shafts, together with the pyrites not yet dissolved in
the water, or
they are carried out from the tunnels; then they are
thrown into vats or
tanks, and boiling water having been poured over
them, the vitriol is freed
and the pyrites are dissolved. This green solution is transferred to other vats
or tanks, that it may
be made clear and pure; it is then boiled in the lead
caldrons until it
thickens; afterward it is poured into wooden tubs, where
it condenses
on rods, or reeds, or twigs, into green vitriol.
Sulphur is made from sulphurous waters, from sulphurous ores, and
from
sulphurous mixtures. These waters are poured into the leaden caldrons
and boiled until they
condense into sulphur. From this latter, heated
together with iron-scales, and transferred into
pots, which are afterward
covered with lute and refined sulphur,
another sulphur is made, which we
call
The ores
other minerals, are melted in
big-bellied earthenware pots. The furnaces,
A—POTS HAVING SPOUTS. B—POTS WITHOUT SPOUTS.
C—LIDS.
which hold two of these pots, are divided into three
parts; the lowest part is a
foot high, and has an opening at the front
for the draught; the top of this is
covered with iron plates, which are
perforated near the edges, and these
support iron rods, upon which the
firewood is placed. The middle part of the
furnace is one and a half feet high, and has a
mouth in front, so that the wood
may be inserted; the top of this has
rods, upon which the bottom of the pots
stand. The upper part is about two feet high, and the pots are also two feet
high and one digit thick; these have below their mouths a long, slender
spout. In order that the mouth of the pot may be covered, an earthenware lid is
made which fits into it. For every two of these pots there must be one pot
which are below the mouth and receive the spouts of the two first pots;
the
third hole is on the opposite side at the bottom, and through it
the sulphur
flows out. In each furnace are placed two pots with spouts, and the furnace
must be
covered by plates of iron smeared over with lute two digits thick; it is
thus entirely closed in, but for two or three ventholes through which
the mouths
of the pots project. Outside of the furnace, against one side, is placed the pot
without a
spout, into the two holes of which the two spouts of the other pots
penetrate, and this pot should be built in at both sides to keep it
steady. When
the sulphur ore has been placed in the pots, and these placed in
the furnace,
they are closely covered, and it is desirable to smear the
joint over with lute,
so that the sulphur will not exhale, and for the
same reason the pot below is
covered with a lid, which is also smeared
with lute. The wood having been
kindled, the ores are heated until the sulphur is
exhaled, and the vapour,
arising through the spout, penetrates into the
lower pot and thickens into
sulphur, which falls to the bottom like
melted wax. It then flows out
through the hole, which, as I said, is at the bottom
of this pot; and the work
man makes it into cakes, or thin sticks
or thin pieces of wood are dipped in it. Then he takes the burning wood and glowing charcoal from the furnace, and
when it has cooled, he opens the two pots, empties the residues, which,
if the
ores were composed of sulphur and earth, resemble naturally
extinguished
ashes; but if the ores consisted of sulphur and earth and
stone, or sulphur
and stone only, they resemble earth completely dried
or stones well roasted. Afterward the pots are re-filled with ore, and the whole work is
repeated.
The sulphurous mixture, whether it consists of stone and sulphur only,
or of stone and sulphur and metal, may be heated in similar pots, but
with
perforated bottoms. Before the furnace is constructed, against the “second”
wall
of the works two lateral partitions are built seven feet high, three feet
long, one and a half feet thick, and these are distant from each other
twenty
seven feet. Between them are seven low brick walls, that measure but
two feet and
the same number of digits in height, and, like the other walls,
are
three feet long and one foot thick; these little walls are at equal
distances from one another, consequently they will be two and one half
feet
apart. At the top, iron bars are fixed into them, which sustain iron plates
three feet long and wide and one digit thick, so that they can bear not
only
the weight of the pots, but also the fierceness of the fire. These plates have
in the middle a round hole one and a half digits wide;
there must not be
more than eight of these, and upon them as many pots
are placed. These
pots are perforated at the bottom, and the same number of whole
pots are
placed underneath them; the former contain the mixture, and
are covered
with lids; the latter contain water, and their mouths are
under the holes
in the plates. After wood has been arranged round the upper pots and
ignited, the
mixture being heated, red, yellow, or green sulphur drips
from it and
flows down through the hole, and is caught by the pots placed
underneath the plates, and is at once cooled by the water. If the mixture
contains metal, it is reserved for smelting, and, if not,
it is thrown away.
A—LONG WALL. B—HIGH WALLS. C—LOW WALLS. D—PLATES.
E—UPPER POTS.
F—LOWER POTS.
The sulphur from such a
mixture can best be extracted if the upper pots are
placed in a vaulted
furnace, like those which I described among other
metallurgical
subjects in Book VIII., which has no floor, but a grate inside;
under
this the lower pots are placed in the same manner, but the plates
must
have larger holes.
Others bury a pot in the ground, and place over it another pot with a
hole at the bottom, in which pyrites or
are
so enclosed that the sulphur cannot exhale. A fierce fire heats the
sulphur, and it drips away and flows down into
the lower pot, which contains
water. (Illustration p. 582).
Bitumen
from mixtures of bituminous
substances. The water, bituminous as well as
A—LOWER POT. B—UPPER POT. C—LID.
salty, at Babylon, as
Pliny writes, was taken from the wells to the salt works
and heated by
the great heat of the sun, and condensed partly into liquid
bitumen and
partly into salt. The bitumen being lighter, floats on the top,
while the salt being
heavier, sinks to the bottom. Liquid bitumen, if there
is much floating on springs, streams and
rivers, is drawn up in buckets or
other vessels; but, if there is
little, it is collected with goose wings, pieces
A—BITUMINOUS SPRING. B—BUCKET. C—POT. D—LID.
of
linen,
and it is boiled in
large brass or iron pots by fire and condensed. As this
bitumen is put to divers uses, some mix pitch with the liquid,
others old
cart-grease, in order to temper its viscosity; these,
however long they are The mixtures containing bitumen
are also treated in the same manner as
those containing sulphur, in pots
having a hole in the bottom, and it
is rare that such bitumen is not highly
esteemed.
Since all solidified juices and earths, if abundantly and copiously mixed
with the water, are deposited in the beds of springs, streams or
rivers, and the
stones therein are coated by them, they do not require
the heat of the sun or
fire to harden them. This having been pondered over by wise men, they dis
covered methods
by which the remainder of these solidified juices and unusual
earths
can be collected. Such waters, whether flowing from springs or
tunnels, are collected in
many wooden tubs or tanks arranged in consecutive
order, and deposit in
them such juices or earths; these being scraped off
every year, are
collected, as
the Harz.
There remains glass, the preparation of which belongs here, for the
reason that it is obtained by the power of fire and subtle art from
certain
solidified juices and from coarse or fine sand. It is transparent, as are certain
solidified juices, gems, and stones;
and can be melted like fusible stones and
metals. First I must speak of the materials from which glass is made;
then of
the furnaces in which it is melted; then of the methods by which it
is
produced.
It is made from fusible stones and from solidified juices, or from other
juicy substances which are connected by a natural relationship. Stones
which are fusible, if they are white and translucent, are more
excellent than
A—MOUTH OF THE TUNNEL. B—TROUGH. C—TANKS. D—LITTLE
TROUGH.
the others, for which reason crystals take the first place. From these, when
pounded, the most excellent transparent glass was made
in India, with which
no other could be compared, as Pliny relates. The second place is accorded
to stones which, although not so hard as
crystal, are yet just as white and
transparent. The third is given to white stones, which are not transparent.
It is necessary, however, first of all to heat all these, and afterward they
are
subjected to the pestle in order to break and crush them into
coarse sand,
and then they are passed through a sieve. If this kind of coarse or fine sand
is found by the glass-makers near
the mouth of a river, it saves them much
labour in burning and
crushing. As regards the solidified juices, the first
place is given to soda; the
second to white and translucent rock-salt; the third
to salts which are
made from lye, from the ashes of the musk ivy, or from
other salty
herbs. Yet there are some who give to this latter, and not to the
former, the
second place. One part of coarse or fine sand made from fusible
stones should be mixed
with two parts of soda or of rock-salt or of herb
salts, to which are
added minute particles of
power of the latter to attract to
itself the vitreous liquid just as it does iron,
and by attracting it
to purify and transform green or yellow into white; and
afterward fire
consumes the When the said juices are not to be had,
two parts of the ashes of oak
or holmoak, or of hard oak or Turkey oak,
or if these be not available,
of beech or pine, are mixed with one part
of coarse or fine sand, and a
small quantity of salt is added, made from salt
water or sea-water, and
a small particle of
white and translucent glass. The ashes should be made from old trees, of
which the trunk at a height
of six feet is hollowed out and fire is put in, and
thus the whole tree
is consumed and converted into ashes. This is done in
winter when the snow lies long, or in summer when it
does not rain, for the
showers at other times of the year, by mixing
the ashes with earth, render
them impure; for this reason, at such
times, these same trees are cut up
into many pieces and burned under
cover, and are thus converted into ashes.
Some glass-makers use three furnaces, others two, others only one.
Those who use three, melt the material in the first, re-melt it in the
second,
A—LOWER CHAMBER OF THE FIRST FURNACE. B—UPPER CHAMBER.
C—VITREOUS MASS.
and in the third they cool the glowing glass
vessels and other articles. Of
these the first furnace must be vaulted and similar to an oven. In the upper
chamber, which is six feet long, four feet wide, and two
feet high, the
mixed materials are heated by a fierce fire of dry wood
until they melt
and are converted into a vitreous mass. And if they are not satisfactorily
purified from dross, they are taken
out and cooled and broken into pieces;
and the vitreous pieces are
heated in pots in the same furnace.
The second furnace is round, ten feet in diameter and eight feet high,
and on the outside, so that it may be stronger, it is encompassed by
five
arches, one and one half feet thick; it consists in like manner of
two
chambers, of which the lower one is vaulted and is one and one half
feet thick. In front this chamber has a narrow mouth, through which the wood
can be
put into the hearth, which is on the ground. At the top and in the
middle of its vault, there is a large round hole
which opens to the upper
chamber, so that the flames can penetrate into
it. Between the arches in
the walls of the upper chamber are eight windows,
so large that the big
bellied pots may be placed through them on to
the floor of the chamber,
around the large hole. The thickness of these pots is about two digits, their
height the same
number of feet, and the diameter of the belly one and a half In the back part of the furnace
is a rectangular hole, measuring in
height and width a palm, through which
the heat penetrates into a third
furnace which adjoins it.
This third furnace is rectangular, eight feet long and six feet wide; it
also consists of two chambers, of which the lower has a mouth in front,
so that
firewood may be placed on the hearth which is on the ground. On each side of
this opening in the wall of the lower chamber is a
recess for oblong earthen
ware receptacles, which are about four
feet long, two feet high, and one and
a half feet wide. The upper chamber has two holes, one on the right side,
the other on the
left, of such height and width that earthenware receptacles
may be
conveniently placed in them. These latter receptacles are three
feet long, one and a half feet high,
the lower part one foot wide, and the
upper part rounded. In these receptacles the glass articles, which have been
blown, are
placed so that they may cool in a milder temperature; if they were
not
cooled slowly they would burst asunder. When the vessels are taken
from the upper chamber, they are immediately
placed in the receptacles
to cool.
A—ARCHES OF THE SECOND FURNACE. B—MOUTH OF THE LOWER CHAMBER.
C—WINDOWS OF THE UPPER CHAMBER. D—BIG-BELLIED POTS.
E—MOUTH OF THE
THIRD FURNACE. F—RECESSES FOR THE
RECEPTACLES. G—OPENINGS IN THE UPPER
CHAMBER. H—OBLONG
RECEPTACLES.
A—LOWER CHAMBER OF THE OTHER SECOND FURNACE. B—MIDDLE ONE.
C—UPPER ONE.
D—ITS OPENING. E—ROUND OPENING.
F—RECTANGULAR OPENING.
Some who use two furnaces partly melt the mixture in the first, and
not
only re-melt it in the second, but also replace the glass articles there.
Others partly melt and re-melt the material in different chambers of the
second furnace. Thus the former lack the third furnace, and the latter,
the first. But this kind of second furnace differs from the other second
furnace,
for it is, indeed, round, but the interior is eight feet in diameter
and twelve feet high, and it consists of three chambers, of which the
lowest is
not unlike the lowest of the other second furnace. In the middle chamber
wall there are six arched openings, in which are
placed the pots to be heated,
and the remainder of the small windows
are blocked up with lute. In the
middle top of the middle chamber is a square opening a palm in
length
and width. Through this the heat penetrates into the upper chamber,
of which the
rear part has an opening to receive the oblong earthenware
receptacles,
in which are placed the glass articles to be slowly cooled. On
this side, the ground of the workshop is higher, or else a bench is
placed there,
so that the glass-makers may stand upon it to stow away
their products
more conveniently.
Those who lack the first furnace in the evening, when they have
accom
plished their day's work, place the material in the pots, so
that the heat during
the night may melt it and turn it into glass. Two boys alternately, during
night and day, keep up the fire by throwing
dry wood on to the hearth. Those
who have but one furnace use the second sort, made with three
chambers. Then in the evening they pour the material into the pots, and in the morning,
having extracted the fused material, they make the glass objects, which
they
place in the upper chamber, as do the others.
The second furnace consists either of two or three chambers, the first of
which is made of unburnt bricks dried in the sun. These bricks are made of a
kind of clay that cannot be easily melted by
fire nor resolved into powder;
this clay is cleaned of small stones and
beaten with rods. The bricks are
laid with the same kind of clay instead of lime. From the same clay the
potters also make their vessels and pots, which
they dry in the shade. These
two parts having been completed, there remains the third.
The vitreous mass having been made in the first furnace in the manner
I
described, is broken up, and the assistant heats the second furnace, in
order
that the fragments may be re-melted. In the meantime, while they are doing
this, the pots are first warmed by
a slow fire in the first furnace, so that the
vapours may evaporate,
and then by a fiercer fire, so that they become red
in drying. Afterward the glass-makers open the mouth of the furnace, and,
seizing
the pots with tongs, if they have not cracked and fallen to pieces,
quickly place them in the second furnace, and they fill them up with
the
fragments of the heated vitreous mass or with glass. Afterward they close
up all the windows with lute and bricks, with the
exception that in each
there are two little windows left free; through
one of these they inspect the
glass contained in the pot, and take it
up by means of a blow-pipe; in the
other they rest another blow-pipe,
so that it may get warm. Whether it
is made of brass, bronze, or iron, the blow-pipe must be
three feet long.
A—BLOW-PIPE. B—LITTLE WINDOW. C—MARBLE. D—FORCEPS.
E—MOULDS BY
MEANS OF WHICH THE SHAPES ARE PRODUCED.
heaped-up clay and the iron shield. The clay holds the blow-pipe when it
is put into the furnace, whereas
the shield preserves the eyes of the glass-maker
from the fire. All this having been carried out in order, the glass-makers
bring the
work to completion. The broken pieces they re-melt with dry wood,
which emits no smoke, but
only a flame. The longer they re-melt it, the purer
and more transparent it becomes,
the fewer spots and blisters there are, and
therefore the glass-makers
can carry out their work more easily. For this
reason those who only melt the material from which glass is
made for one
night, and then immediately make it up into glass
articles, make them less
pure and transparent than those who first
produce a vitreous mass and then
re-melt the broken pieces again for a
day and a night. And, again, these make
a less pure and transparent glass than do those
who melt it again for two days
and two nights, for the excellence of
the glass does not consist solely in the
material from which it is
made, but also in the melting. The glass-makers
often test the glass by drawing it up with the
blowpipes; as soon as they
observe that the fragments have been
re-melted and purified satisfactorily,
each of them with another
blow-pipe which is in the pot, slowly stirs and takes
up the glass
which sticks to it in the shape of a ball like a glutinous, coagulated
gum. He takes up just as much as he needs to complete the article he wishes
to make; then he presses it against the lip of marble and kneads it
round and
round until it consolidates. When he blows through the pipe he blows as
he would if inflating a
bubble; he blows into the blow-pipe as often as it is
necessary,
removing it from his mouth to re-fill his cheeks, so that his breath
does not draw the flames into his mouth. Then, twisting the lifted blow-pipe
round his head in a circle, he makes
a long glass, or moulds the same in a
hollow copper mould, turning it
round and round, then warming it again,
blowing it and pressing it, he
widens it into the shape of a cup or vessel, or of
any other object he
has in mind. Then he again presses this against the
marble to flatten the bottom,
which he moulds in the interior with his other
blow-pipe. Afterward he cuts out the lip with shears, and, if necessary, adds
feet
and handles. If it so please him, he gilds it and paints it with various
colours. Finally, he lays it in the oblong earthenware receptacle, which is
placed in the third furnace, or in the upper chamber of the second
furnace,
that it may cool. When this receptacle is full of other slowly-cooled articles,
he passes
a wide iron bar under it, and, carrying it on the left arm, places it
in another recess.
The glass-makers make divers things, such as goblets, cups, ewers, flasks,
dishes, plates, panes of glass, animals, trees, and ships, all of which
excellent and
wonderful works I have seen when I spent two whole years
in Venice some
time ago. Especially at the time of the Feast of the Ascension they were on
sale
at Morano, where are located the most celebrated glass-works. These I
saw on other occasions, and when, for a certain reason, I
visited Andrea
Naugerio in his house which he had there, and conversed
with him and
Francisco Asulano.
END OF BOOK XII.
AGRICOLA'S WORKS.
Georgius agricola was not only the author of
works on Mining and allied
subjects, usually asso
ciated with his name, but he also interested
himself
to some extent in political and religious subjects. For convenience in discussion we may, therefore,
divide his writings on
the broad lines of (1) works on
mining, geology, mineralogy, and allied
subjects; (2)
works on other subjects, medical, religious, critical,
political, and historical. In respect especially to the
first division, and partially with regard
to the others, we find three principal
cases: (
(
have been unable to authenticate; and (
published or lost. The following are the short titles of all of the published
works which
we have been able to find on the subjects allied to mining,
arranged
according to their present importance:—
edition, 1556;
Subterraneorum,
Metallicarum
Interpretatio,
first edition, 1533;
Veteribus et Novis Metallis,
ex Terra,
Of the “lost” or unpublished works, on which there is some
evidence,
the following are the most important:—
Metallorum Defensio ad Jacobum Scheckium, De Jure et Legíbus
Metallicis,
De Varía Temperie síve Constitutione
Aerís, De Terrae Motu,
tariorum, Librí VI.
The known published works upon other subjects are as follows:—Latin
Grammar, first edition, 1520; Two Religious Tracts, first edition,
1522;
Turcam,
The lost or partially completed works on subjects unrelated to mining,
of which some trace has been found, are:—
díne solidas
partes,
et Toringiae,
De Tradítioníbus Apostolícis, Oratío de rebus
gestis Ernesti et
Alberti, Ducum Saxoniae.
REVIEW OF PRINCIPAL WORKS.
Before proceeding with the bibliographical detail, we consider it desirable
to review briefly the most important of the author's works on subjects
related
to mining.
This is the most important work of Agricola,
excepting It has always been printed in combination with
other works, and first
appeared at Basel, 1546. This edition was considerably
revised by the
author, the amended edition being that of 1558, which we have
used in
giving references. The work comprises ten “books” of a total of
217 folio
pages. It is the first attempt at systematic mineralogy, the minerals
being classified into (1)
“earths” (clay, ochre, etc.), (2) “stones properly
so
called” (gems, semi-precious and unusual stones, as
distinguished from rocks),
(3) “solidified juices” (salt,
vitriol, alum, etc.), (4) metals, and (5) “com
pounds”
(homogeneous “mixtures” of simple substances, thus forming
such minerals as galena, pyrite, etc.). In this classification Agricola
en
deavoured to find some fundamental basis, and therefore adopted
solubility,
fusibility, odour, taste, etc., but any true classification
without the atomic
theory was, of course, impossible. However, he makes a very creditable
performance out of their properties
and obvious characteristics. All of the
external characteristics which we use to-day in
discrimination, such as colour,
hardness, lustre, etc., are enumerated,
the origin of these being attributed to
the proportions of the
Peripatetic elements and their binary properties. Dana, in his great work
as having been described by
Agricola and his predecessors, accredits a score to
Agricola himself. It is our belief, however, that although in a few cases
Agricola has
been wrongly credited, there are still more of which priority in
description might be assigned to him. While a greater number than four
score of so-called species are
given by Agricola and his predecessors, many
of these are, in our
modern system, but varieties; for instance, some eight
or ten of the
ancient species consist of one form or another of silica.
Book I. is devoted to mineral characteristics—colour, brilliance,
taste,
shape, hardness, etc., and to the classification of minerals;
Book II.,
“earths”—clay, Lemnian earth, chalk, ochre,
etc.; Book III., “solidified
juices”—salt,
bitumen, coal, bituminous shales,
amber; Book V., lodestone, bloodstone,
gypsum, talc, asbestos, mica,
calamine, various fossils, geodes, emery, touch
stones, pumice,
fluorspar, and quartz; Book VI., gems and precious stones;
Book VII.,
“rocks”—marble, serpentine, onyx, alabaster, limestone,
etc.;
Book VIII., metals—gold, silver, quicksilver, copper, lead,
tin, antimony,
bismuth, iron, and alloys, such as electrum, brass,
etc.; Book IX., various
furnace operations, such as making brass,
gilding, tinning, and products such
as slags, furnace accretions,
hearth-lead, verdigris, white-lead, red-lead, etc.;
Book X., “compounds,”
embracing the description of a number
of recognisable silver, copper, lead,
quicksilver, iron, tin, antimony,
and zinc minerals, many of which we set
out more fully in Note 8, page
108.
This work also has always been
published in company with others. The first edition was printed at Basel,
by
the author, has been used by us for reference. There are five “books,” and
in the main they contain
Agricola's philosophical views on geologic phenomena. The largest portion of the actual text is occupied with refutations of the
ancient philosophers, the alchemists, and the astrologers; and these
portions,
while they exhibit his ability in observation and in
dialectics, make but dull
reading. Those sections of the book which contain his own views, however,
are of
the utmost importance in the history of science, and we reproduce
extensively the material relating to ore deposits in the footnotes on
pages 43
to 52. Briefly, Book I. is devoted to discussion of the origin
and distribution
of ground waters and juices. The latter part of this book and a portion of
Book II. are devoted to
the origin of subterranean heat, which he assumes
is in the main due to
burning bitumen—a genus which with him embraced
coal—and
also, in a minor degree, to friction of internal winds and to
burning
sulphur. The remainder of Book II. is mainly devoted to the dis
cussion of
subterranean “air”, “vapour”, and
“exhalations”, and he con
ceives that volcanic
eruptions and earthquakes are due to their agency, and
in these
hypotheses he comes fairly close to the modern theory of eruptions
from
explosions of steam. “Vapour arises when the internal heat of the
earth or some hidden
fire burns earth which is moistened with vapour. When heat or subterranean fire meets with a great force of vapour which
cold has contracted and encompassed in every direction, then the
vapour,
finding no outlet, tries to break through whatever is nearest
to it, in order
to give place to the insistent and urgent cold. Heat and cold cannot abide
together in one place, but expel and drive
each other out of it by turns”.
As he was, we believe, the first to recognise the fundamental agencies
of mountain sculpture, we consider it is of sufficient interest to
warrant a
reproduction of his views on this subject: “Hills and
mountains are pro
duced by two forces, one of which is the power of
water, and the other the
strength of the wind. There are three forces which loosen and demolish
the mountains, for in
this case, to the power of the water and the strength
of the wind we
must add the fire in the interior of the earth. Now we can
plainly see that a great abundance of water produces
mountains, for the
torrents first of all wash out the soft earth, next
carry away the harder
earth, and then roll down the rocks, and thus in
a few years they excavate
the plains or slopes to a considerable depth;
this may be noticed in moun
tainous regions even by unskilled
observers. By such excavation to a
great depth through many ages, there rises an
immense eminence on each
side. When an eminence has thus arisen, the earth rolls down, loosened by
constant rain and split away by frost, and the rocks, unless they are
exceed
ingly firm, since their seams are similarly softened by the
damp, roll down
into the excavations below. This continues until the steep eminence is
changed into a slope. Each side of the excavation is said to be a mountain,
just as the bottom
is called a valley. Moreover, streams, and to a far greater
extent rivers, effect the same
results by their rushing and washing; for this
reason they are
frequently seen flowing either between very high mountains
Nor did the hollow places which now contain the seas all formerly
exist,
nor yet the mountains which check and break their advance, but
in many
parts there was a level plain, until the force of winds let
loose upon it a
tumultuous sea and a scathing tide. By a similar process the impact of
water entirely overthrows and
flattens out hills and mountains. But
these changes of local conditions, numerous and important as they
are, are
not noticed by the common people to be taking place at the
very moment
when they are happening, because, through their antiquity,
the time, place,
and manner in which they began is far prior to human
memory. The wind
produces hills and mountains in two ways: either when set loose
and free
from bonds, it violently moves and agitates the sand; or else
when, after
having been driven into the hidden recesses of the earth by
cold, as into a
prison, it struggles with a great effort to burst out. For hills and mountains
are created in hot countries, whether they are
situated by the sea coasts or
in districts remote from the sea, by the
force of winds; these no longer held
in check by the valleys, but set
free, heap up the sand and dust, which they
gather from all sides, to
one spot, and a mass arises and grows together. If
time and space allow, it grows together and hardens, but if it be not
allowed
(and in truth this is more often the case), the same force
again scatters the
sand far and wide. . . . Then, on the other hand, an
earthquake
either rends and tears away part of a mountain, or engulfs
and devours the
whole mountain in some fearful chasm. In this way it is recorded the
Cybotus was destroyed, and it is believed
that within the memory of man
an island under the rule of Denmark
disappeared. Historians tell us that
Taygetus suffered a loss in this way, and that
Therasia was swallowed up
with the island of Thera. Thus it is clear that water and the powerful
winds produce mountains,
and also scatter and destroy them. Fire only
consumes them, and does not produce at all, for part of the
mountains—
usually the inner part—takes fire.”
The major portion of Book III. is devoted to the origin of ore channels,
which we reproduce at some length on page 47. In the latter part of
Book
III., and in Books IV. and V., he discusses the principal
divisions of the mineral
kingdom given in It involves a large amount of what now appears fruitless tilting at the
Peripa
tetics and the alchemists; but nevertheless, embracing, as
Agricola did, the
fundamental Aristotelian elements, he must needs find
in these same ele
ments and their subordinate binary combinations
cause for every variation in
external character.
This, Agricola's first work in relation to mining, was appa
rently
first published at Basel, 1530. The work is in the form of a dialogue
between “Bermannus,” who is described as a miner,
mineralogist, and “a
student of mathematics and poetry,”
and “Nicolaus Ancon” and “Johannes
Neavius,”
both scholars and physicians. Ancon is supposed to be of philoso
phical turn of mind and a student
of Moorish literature, Naevius to be par
ticularly learned in the
writings of Dioscorides, Pliny, Galen, etc. “Berman-
Berman, a prominent miner. The book is in the main devoted to a correla
tion of the minerals
mentioned by the Ancients with those found in the Saxon
mines. This phase is interesting as indicating the natural trend of Agricola's
scholastic mind when he first comes into contact with the sciences to
which
he devoted himself. The book opens with a letter of commendation from
Erasmus, of Rotterdam,
and with the usual dedication and preface by the
author. The three conversationalists are supposed to take walks among the
mines
and to discuss, incidentally, matters which come to their attention;
therefore the book has no systematic or logical arrangement. There are
occasional statements bearing on the history, management,
titles, and methods
used in the mines, and on mining lore generally. The mineralogical part, while
of importance from the point of view of
giving the first description of several
minerals, is immensely improved
upon in
15 years later. It is of interest to find here the first appearance of the names
of many
minerals which we have since adopted from the German into our own
nomenclature. Of importance is the first description of bismuth, although,
as pointed
out on page 433, the metal had been mentioned before. In the
revised collection of collateral works published in 1558, the
author makes
many important changes and adds some new material, but
some of the later
editions were made from the unrevised older
texts.
This list of German equivalents
for Latin mineralogical terms was
prepared by Agricola himself, and first
appears in the 1546 collection
of
being repeated in all subsequent
publications of these works. It consists of
some 500 Latin mineralogical and metallurgical terms,
many of which are of
Agricola's own coinage. It is of great help in translation and of great value
in the study of
mineralogic nomenclature.
This work is devoted to a discussion of the
Greek and Roman weights and
measures, with some correlation to those used
in Saxony. It is a careful work still much referred to by students of these
subjects. The first edition was published at Paris in 1533, and in the 1550
edition at Basel appears, for the first time,
This short work comprises 31 folio
pages, and first appears in the 1546
collection of collateral works. It consists
mainly of historical and geographical references to the
occurrence of metals
and mines, culled from the Greek and Latin
classics, together with some
information as to the history of the mines
in Central Europe. The latter
is the only original material, and unfortunately is not very
extensive. We
have incorporated some of this information in the footnotes.
This short work was first printed in
Basel, 1549, and consists of one
chapter of 23 folio pages. Practically the whole
is devoted to the discussion of various animals
who at least a portion of their
time live underground, such as
hibernating, cave-dwelling, and burrowing
animals, together with
cave-dwelling birds, lizards, crocodiles, serpents,
etc. There are only a few lines of remote geological interest as to migration
This book also discloses an occasional vein of credulity not to be expected
from
the author's other works, in that he apparently believes
Aristotle's story of
the flies which were born and lived only in the
smelting furnace; and further,
the last paragraph in the book is
devoted to underground gnomes. This we
reproduce in the footnote on page 217.
This work of four books,
comprising 83 folio pages, first appears in
the 1546 collection. As the title
indicates, the discussion is upon the substances which flow
from the earth,
such as water, bitumen, gases, etc. Altogether it is of microscopic value and
wholly uninteresting. The major part refers to colour, taste, temperature,
medicinal uses of
water, descriptions of rivers, lakes, swamps, and aqueducts.
BIBLIOGRAPHICAL NOTES.
For the following we have mainly to thank Miss Kathleen Schlesinger, who has
been
employed many months in following up every clue, and although the
results display
very considerable literary activity on the part of the
author, they do not by any means
indicate Miss Schlesinger's labours. Agricola's works were many of them published at
various times in
combination, and therefore to set out the title and the publication of each
work separately would involve much repetition of titles, and we
consequently give the titles
of the various volumes arranged according
to dates. For instance,
Ortu et
Causis, De Veteribus et Novis Metallis, De Natura eorum quae Effluunt ex
Terra,
these works always
include Moreover, the Latin
1657 includes all of these works.
We mark with an asterisk the titles to editions which we have been able to
authen
ticate by various means from actual books. Those unmarked are editions which we are
satisfied do exist, but the
titles of which are possibly incomplete, as they are taken from
library
catalogues, etc. Other editions to which we find reference and of which we are not
certain are noted separately in the discussion later on.
*1530 (8vo).
(Froben's mark).
MDXXX.
Bound with this edition is (p.
131-135), at least occasionally,
appellationes juxta vernaculam Germanorum linguam, autori
Plateano.
MDXXX.
*1533 (8vo):
à Budaeo et Portio parum
animadversa diligenter excutiuntur. Opus nunc primum in lucem
aeditum.
(Wechelus's Mark).
Excudebat Christianus Wechelus, in vico Iacobaeo, sub scuto Basileiensi,
Anno
MDXXXIII.
261 pages and index of 5 pages.
*1533 (4to):
De Mensuris et Ponderibus: In quibus
pleraque à Budaeo et Portio
parum animadversa diligenter excutiuntur.
(F
ad sex annos.
1534 (4to):
Epistola ad Plateanum, cui sunt adiecta aliquot loca castigata in
libris
de mensuris et ponderibus nuper editis.
Froben, Basel, 1534.
*1535 (8vo):
Budaeo et Portio parum
animadversa diligenter excutiuntur.
(Printer's Mark).
At the end of Index:
de Nicolinis de Sabio, sumptu vero et
requisitione Anno.
On back of title page is given:
suris Graecis, Tertius de rerum
quas metimur pondere, Quartus de ponderibus Romanis,
Quintus de
ponderibus Graecis.
*1541 (8vo):
Apud Hieronymum Gormontiú.
In Vico Jacobeo sub signotrium coronarum.
1541.
*1546 (8vo):
et emendatione nunc primum editus cum
nomenclalura rerum metallicarum.
MDXLVI.
*1546 (folio):
De natura eorum quae
effluunt ex terra Lib. IIII.
De natura fossilium Lib.
X.
De veteribus et novis metallis, Lib.
II.
Bermannus sive De re Metallica dialogus.
Interpretatio Germanica vocum rei metallicae addito
Indice
faecundissimo.
Imp. Maiestatis ad quinquennium.
*1549 (8vo):
Froben, Basel, MDXLIX.
*1550 (8vo):
loro effetti e natura, Lib. V. De La Natura di quelle cose, che de la terra scorrono Lib.
IIII.
De
La Natura de le cose Fossili, e che sotto la terra si Cavano Lib. X. De Le Minere antiche e
moderne Lib. II. Il Bermanno, ò de le cose Metallice Dialogo, Recato tutto hora dal
Latino
in Buona Lingua volgare.
(Vignette of Sybilla surrounded by the words)—
Mio Presaggio.
Et del Illustriss.
Senato Veneto per
anni. XX.
(Colophon).
*1550 (folio):
De Mensuris et ponderibus Rom.
atque Graec.
lib. V.
De externis
mensuris et ponderibus Lib. II. Ad ea quae Andreas Alciatus denuo disputavit De Men
suris et
Ponderibus brevis defensio Lib. I.
De Mensuris quibus intervalla metimur Lib. I.
De restituendis ponderibus atque mensuris.
Lib. I.
De precio metallorum et monetis.
Lib.
III.
Froben.
MDL.
Maiestatis ad quinquennium.
*1556 (folio):
omnia denique ad Metallicam
spectantia, non modo luculentissime describuntur, sed et per effigies,
suis locis insertas, adjunctis Latinis, Germanicisque appellationibus
ita ob oculos ponuntur,
ut clarius tradi non possint Eiusdem De
Animantibus Subterraneis Liber, ab Autore recognitus:
cum Indicibus
diversis, quicquid in opere tractatum est, pulchre demonstrantibus.
(Froben's Mark).
Cum Privilegio Imperatoris in annos V. et Galliarum Regis ad
Sexennium.
Folio 538 pages and preface, glossary and index amounting to 86 pages.
This is the
first edition of We reproduce this title-page on page XIX.
*1557 (folio):
Handel gehörig, mitt
schönen figuren vorbildet, und Klärlich beschriben seindt erstlich
in
Lateinischer Sprach durch den Hochgelerten und weittberümpten
Herrn Georgium Agricolam,
Doctorn und. Bürgermeistern der Churfürstlichen statt Kempnitz, jezundt aber
verteüscht durch
den Achtparen, unnd Hochgelerten Herrn Philippum
Bechium, Philosophen, Artzer und in der
Loblichen Universitet zu Basel
Professorn.
Keiserlicher Freyheit.
*1558 (folio):
De natura eorum quae
effluunt ex terra Lib. IV.
De natura fossilium Lib.
X.
De veteribus et novis meiallis Lib.
II.
Bermannus, sive De Re Metallica Dialogus Liber. Interpretatio Germanica vocum rei metallicae,
addito duplici Indice,
altero rerum, altero locorum Omnia ab ipso authore, cum haud poenitenda
accessione, recens recognita.
Basileae
Maiestatis renovato privilegio ad quin
quennium.
270 pages and index.
As the title states, this is a revised edition by the author, and
as the
changes are very considerable it should be the one used. The Italian translation
and the 1612 Wittenberg edition, mentioned
below, are taken from the 1546 edition, and are,
therefore, very
imperfect.
*1561 (folio):
Second edition of
title as the
first edition except the addition, after the body of the title, of the words
omnibus nunc iterum ad archetypum
diligenter restitutis et castigatis
pages and 72 pages of glossary and index.
*1563 (folio):
tutte le sorti, e qualità
de gli uffizii, de gli strumenti, delle macchine, e di tutte l'altre cose
attenenti
a cotal arte, non pure con parole chiare ma eziandio si
mettano a luoghi loro le figure di dette
cose, ritratte al naturale,
con l'aggiunta de nomi di quelle, cotanto chiari, e spediti, che meglio non
si puo desiderare, o havere.
corretto et riveduto. Tradotti in lingua Toscana da M.
Michelangelo Florio Fiorentino.
Frobenio et Nicolao Episcopio,
542 pages with 6 pages of index.
*1580 (folio):
diesem Handel gehörig mit
figuren vorgebildet und klärlich beschriben, etc. Durch den Hoch
gelehrten . . . . Herrn Georgium Agricolam der
Artzney Doctorn und Burgermeister
der Churfürstlichen Statt
Kemnitz erstlich mit grossem fleyss mühe und arbeit in Latein
beschriben
und in zwölff Bücher abgetheilt: Nachmals aber
durch den Achtbarn und auch Hochgelehrten
Philippum Bechium Philosophen
Artzt und in der Löblichen Universitet zu Basel Professorn
mit
sonderm fleyss Teutscher Nation zu gut verteutscht und an Tag geben. Allen Berckherrn
Gewercken Berckmeistern Geschwornen Schichtmeistern
Steigern Berckheuwern Wäschern
und Schmeltzern nicht allein
nützlich und dienstlich sondern auch zu wissem hochnotwendig.
May Freyheit nicht nachzutrucken.
Im Jahr
*1612 (12mo):
De natura eorum quae
effluunt ex terra, Lib. IV.
De natura fossilium Lib.
X.
De veteribus et novis metallis Lib.
II.
Bermannus, sive de re metallica Dialogus. Interpretatio Germanica vocum rei metallicae.
nationum doctissimis viris,
valde desiderati et expetiti.
capitum argumentis, et nonnullis
scholiis marginalibus illustrati à Johanne Sigfrido Philos: et
Medicinae Doctore et in illustri Julia Professore ordinario.
Georgii Fabricii, quibus
ea potissimum explicantur, quae Georgius Agricola praeteriit.
There are 970 pages in the work of Agricola proper, the notes of Fabricius
comprising
a further 44 pages, and the index 112 pages.
*1614 (8vo):
nunc vero in gratiam studiosorum
seorsim editus, in certa capita divisus, capitum argumentis et
nonnullis marginalibus exornatus à Johanne Sigfrido, Phil. & Med.
Doctore,
Schureri Bibliop.
Anno.
MDCXIV.
*1621 (folio):
De Re Metallica Libri XII
Quibus Officia, Instrumenta, Machinae, ac
omnia denique ad metallicam spectantia, non modo
Luculentissimè
describuntur; sed et per effigies, suis locis insertas adjunctis Latinis. German
icisque; appellationibus, ita ob oculos ponuntur, ut clarius
tradi non possiut.
quicquid in Opere tractatum est,
pulchrè demonstrantibus.
(Vignette of man at assay furnace).
Sumptibus itemque typis chalcographicis Ludovici Regis Anno
502 pages and 58 pages glossary and mdices.
*1621 (folio):
disem Handel gehörig mit Figuren
vorgchildet und klärlich beschrieben: . . . . Durch
den
Hochgelehrten und weitberühmten Herrn Georgium Agricolam, der Artzney
Doctorn und
Burgermeister der Churfürstlichen Statt Kemnitz
Erstlich mit grossem fleiss mühe und arbeit in
Latein beschrieben
und in zwölſſ Bücher abgetheilt: Nachmals aber durch
den Achtbarn und
auch Hochgelehrten Philippum Bechium. Philosophen, Artzt, und in der loblichen Universitet zu
Basel Professorn
mit sonderm fleiss Teutscher Nation zu gut verteutscht und an Tag geben und
nun zum andern mal getruckt.
Berghäwern Wäschern unnd Schmeltzern
nicht allein nutzlich und dienstlich sondern auch zu
wissen
hochnohtwendig.
(Vignette of man at assay furnace).
491 pages 5 pages glossary—no index.
*1657 (folio):
De Re Metallica Libri
XII. Quibus Officia, instrumenta, machinae, ac omnia denique ad metallicam
spectantia, non
modo luculentissimè describuntur: sed et per
effigies, suis locis insertas, adjunctis Latinis,
Germanicisque
appellationibus, ita ob oculos ponuntur, ut clarius tradi non possint. Quibus
accesserunt hac ultima editione, Tractatus ejusdem argumenti, ab
eodem conscripti, sequentes.
V., De
Natura eorum quae effluunt ex Terra Lib. IV., De Natura Fossilium
Lib. X., De Veteribus et
Novis Metallis Lib. II., Bermannus sive de Re
Metallica, Dialogus Lib. I.
(Vignette of assayer and furnace).
Anno
Folio, 708 pages and 90 pages of glossary and indices.
This is a very serviceable
edition of all of Agricola's important works,
and so far as we have noticed there are but few
typographical
errors.
*1778 (8vo):
Deutsche
übersetzet, mit nützl. Anmerkungen erläutert.
u.
mit einem ganz neuen Zusatze von
Zlüglicher Anstellung des
Bergbaues u. von der Zugutemachung der Erze auf den Hüttenwerken
versehen von
Johann Gottlieb Stör.
d.
Fulda, Hermstädt
*1806 (8vo):
übersetzt und mit Exkursionen
herausgegeben von Friedrich August Schmid. Haushalts-und
Befahrungs-Protokollist im Churf. vereinigten Bergamte zu St.
Annaberg.
*1807-12 (8vo):
Begleitet von Ernst Lehmann Bergamts-Assessor, Berg-Gegen-und Receszschreiber
in Dem
Königl. Sächs.
Bergamte Voigtsberg der jenaischen Societät für die gesammte
Mineralogie
Ehrenmitgliede.
This German translation consists of four parts: the first being
the
second
Fossilium,
parts.
We give the following notes on other possible prints, as a great many
references to the
above works occur in various quarters, of date other
than the above. Unless otherwise
convinced it is our belief that most of these refer to
the prints given above, and are due to
error in giving titles or dates. It is always possible that such prints do exist and have escaped
our
search.
Leupold, Richter, Schmid, van der Linden, Mercklinus and Eloy
give an
8vo edition of
found no trace of
this print. Leupold, van der Linden, Richter, Schmid and Eloy mention
an 8vo
edition, Wittenberg, 1614. It is our belief that this refers to the 1612
Wittenberg
edition of the selected works, which contains a somewhat
similar title referring in reality
to Ferguson
mentions a German edition, Schweinfurt, 8vo, 1687. We can find
no trace of this; it may
refer to the 1607 Schweinfurt edition
mentioned above.
Leupold and Gatter refer to a folio edition of 1550. This was
probably
an error for either the 1546 or the 1558 editions. Watt refers to an edition of 1561
combined with We find no trace of such edition, nor even that the
latter work was
ever actually printed. He also refers to an edition of 1614 and one of 1621,
this probably
being an error for the 1612 edition of the subsidiary works and the
Metallica
1612.
Albinus, Hofmann, Jacobi, Schmid, Richter, and Reuss mention
an edition
of 1544. This we believe to be an error in giving the date of the dedication
instead
of that of the publication (1546). Albinus and Ferguson give an
edition of 1555, which date
is, we believe, an error for 1558. Ferguson
gives an edition of the Italian translation as
1559; we believe this
should be 1550. Draud gives an edition of 1621; probably this
should be
1612.
Albinus, Schmid, Reuss, Richter, and Weinart give the first edition as
1528. We have been unable to learn of any actual copy of that date, and
it is our belief that
the date is taken from the dedication instead of
from the publication, and should be 1530.
Leupold, Schmid, and Reuss
give an edition by Froben in 1549; we have been unable to
confirm this. Leupold also gives an edition of 1550 (folio), and Jöcher gives an
edition of
Geneva 1561 (folio); we have also been unable to find this,
and believe the latter to be a
confusion with the
lished by itself in folio. The catalogue of the library at Siena (Vol.
III., p.
78) gives
Bermanno, Vinegia,We have found no trace of this edition elsewhere.
Albinus and Schmid mention an edition of 1539, and one
of 1550. The
Biographie Universelle, Paris, gives one of 1553, and Leupold one of 1714,
all
of which we have been unable to find. An epitome of this work was published at various
times, sometimes in
connection with editions of Vitruvius; so far as we are aware on the
following dates, 1552, 1585, 1586, 1829. There also appear extracts in
relation to liquid
measures in works entitled Paul Eber
and Caspar Peucer,
Watt gives an edition, Basel, 1530, and Paris, 1541;
we believe this is
incorrect and refers to Reuss mentions a folio print of Basel,
1550. We consider this very
unlikely.
Albinus, Hofmann, Schmid, Jacobi,
Richter, Reuss, and Weinart give an
edition of 1545. We believe this is again the dedication
instead of the
publication date (1546).
Van der Linden gives an edition at Schweinfurt,
8vo, 1607. Although we
have been unable to find a copy, this slightly confirms the
possibility
of an octavo edition of
together. Leupold gives assurance that he handled an octavo edition of Wittenberg,
1612,
We think he confused this with
of that date and place. Schmid, Richter, and Draud all refer to an edition similarly annotated,
Leipzig, 1613, 8vo. We have no trace of it otherwise.
UNPUBLISHED WORKS ON SUBJECTS RELATED TO MINING.
Agricola apparently projected a complete series of works covering the whole
range of
subjects relating to minerals: geology, mineralogy, mining,
metallurgy, history of metals,
their uses, laws, etc. In a letter
that Agricola intended writing about
30 books (chapters) in addition to those already pub
lished, and to
the twelve books Apparently
a number of these works were either unfinished or unpublished
at Agricola's death, for his
friend George Fabricius seems to have made
some effort to secure their publication, but did
not succeed, through
lack of sympathy on the part of Agricola's family. Hofmann
this matter:
“His intentions were frustrated mainly through the lack of support
with which
he was met by the heirs of the Mineralogist. These, as he complains to a Councillor of the
Electorate, Christopher
von Carlovitz, in 1556, and to Paul Eber in another letter, adopted
a
grudging and ungracious tone with regard to his proposal to collect all
Agricola's works
left behind, and they only consented to communicate to
him as much as they were obliged At the Prince's command they showed him a little,
but he supposed that
there was much more that they had suppressed or not preserved. The attempt to purchase some of the works—the Elector had given
Fabricius money for
the purpose (30 nummos unciales)—proved
unavailing, owing to the disagreeableness of
Agricola's heirs. It is no doubt due to these regrettable circumstances that all the works
of the industrious scholar did not come down to us.” The
“disagreeableness” was pro
bably due to the refusal of
the Protestant townsfolk to allow the burial of Agricola in the
Cathedral at Chemnitz. So far as we know the following are the unpublished or lost works.
This work on mining law is mentioned at the end of
Book IV. of We
have been unable to find any evidence that it was ever published.
In a letter
refers to having a work in hand of this title.
Hofmann
Basel 1543, was sold to someone in America by
a Frankfort-on-Main bookseller in 1896.
This is apparently the only
reference to it that we know of, and it is possibly a confusion of
titles or a “separate” of some chapters from
Referred to by Fabricius in a
letterIf published was probably only a tract.
In a letter
1, 1544) is some reference
which might indicate that he was formulating
a work on earthquakes under this title, or
perhaps may be only
incidental to the portions of
subterraneis explicat, Libri VI. Agricola apparently partially completed a work under some
such title as
this, which was to embrace chapters entitled
The main object seems to
have been a commentary on the terms and passages in the classics
relating to mining, mineralogy, etc. It is mentioned in the Preface of
Metallis,
that Agricola should defer sending his new
commentaries until the following spring. The
work is mentioned by Albinus
Jan. 1548,
28, 1555,
a third from
Fabricius to Melanchthon on December 8th, 1555
that the work was not
completed by Agricola.
WRITINGS NOT RELATED TO MINING, INCLUDING LOST OR UNPUBLISHED
WORKS.
This was probably the first of Agricola's publications, the full title
to which is Excusum Lipsiae in Officina Melchioris Lottheri.
Anno
some reason to believe that
Agricola also published a Greek grammar, for there is a letter
from Agricola dated March 18th,
1522, in which Henicus Camitianus is requested to send a
copy to
Stephan Roth.
There are preserved in the Zwickau Rathsschul Library
by Stephan Roth of two tracts,
the one entitled,
other.
dicit in Christo. The former was written from Leipzig in 1522, and the latter, although
not dated, is assigned to the same period. Both are printed in
des Georg Agricola,
Dresden, 1900. There is
some reason (from a letter of Fabricius to Melanchthon, Dec. 8th,
1555) to believe that Agricola had completed a work on the
unwritten traditions concerning
the Church. There is no further trace of it.
Agricola appears to have been joint author with Andreas Asulanus and J. B.
Opizo of a revision of this well-known Greek work.
It was published at Venice in 1525,
under the title of Agricola's name is mentioned in a prefatory
letter to Opizo by
Asulanus.
This political tract, directed against the Turks, was written in
Latin
and first printed by Froben, Basel, 1528. It was translated into German
apparently
by Agricola's friend Laurenz Berman, and published under the
title
Vormanunge . . . .
widder den Türcken
(8vo), and either in 1530 or 1531 by Wolfgang
Stöckel, Dresden, 4to. It was again printed
in Latin by Froben, Basel, 1538, 4to; by H.
Grosius, Leipzig, 1594, 8vo; it was included
among other works
published on the same subject by Nicholas Reusnerus, Leipzig, 1595;
by
Michael Lantzenberger, Frankfurt-am-Main, 1597, 4to. Further, there is reference by
Watt to an edition at Eisleben, 1603, of
which we have no confirmation. There is another
work on the subject, or a revision by the author
mentioned by Albinus
after Agricola's death, sent to Froben by George Fabricius to be
printed; nothing further
appears in this matter however.
This work on the Plague appears to have been first printed by Froben,
Basel, 1554, 8vo. The work was republished at Schweinfurt, 1607, and at Augsburg in
1614,
under various editors. It would appear from Albinus
Agricola and in Froben's hands for publication
after the author's death.
This work is referred to by Agricola himself in
Eorum,
letter of Agricola to
Sebastian Munster on the subject. Albinus states (
193)
that to his knowledge it had not yet been published. Conrad Gesner, in his work
torum et
observationum de Thermis,
Agricola's
instituerit copiosus se dicturum pollicetur. Watts mentions it as having been published in 1549,
1561, 1614, and
1621. He, however, apparently confuses it with We
are unable to state whether it was ever printed or not. A note of inquiry to the principal
libraries in Germany gave a negative
result.
This work, according to
Albinus was received by Fabricius a year after
Agricola's death, but whether it was published
or not is
uncertain.
This work is referred to by Agricola in the
preface of
of the work. There is no evidence of publication.
It seems from Agricola's letter
Agricola prepared some sort of a work on the history of
Saxony and of the Royal Family
published as written by Agricola. Albinus, Hofmann, and Struve give some details of letters
in reference
to it. Fabricius in a letter
11, 1536 asks Meurer to send Agricola
some material for it; in a letter
from Fabricius to Meurer dated Oct. 30, 1554, it appears
that the Elector had granted Agricola 200 thalers
to assist in the work. After Agricola's
death the material seems to have been handed over to
Fabricius, who made use of it (as he
states in the preface) in
preparing the work he was commissioned by the Elector to write,
the
title of which was,
Leipzig, 1597. It includes on page 880 a fragment of a work entitled
Ernesti et Alberti
Ducum Saxoniae,
WORKS WRONGLY ATTRIBUTED TO GEORGIUS AGRICOLA.
The following works have been at one time or another wrongly attributed to
Georgius
Agricola:—
1534, by
one Daniel Agricola, which is merely a controversial book with a
catch-title, used
by Catholics for converting heretics.
slightly of
transmutation.
ANCIENT AUTHORS.
We give the following brief notes on early works containing some reference to
miner
alogy, mining, or metallurgy, to indicate the literature
available to Agricola and for historical
notes bearing upon the
subject. References to these works in the footnotes may be most
easily consulted
through the personal index.
GREEK AUTHORS.—Only a very limited Greek literature upon subjects
allied to
mining or natural science survives. The whole of the material of technical interest could be
reproduced on
less than twenty of these pages. Those of most importance are: Aristotle
(384-322 B.C.), Theophrastus
(371-288 B.C.), Diodorus Siculus (1st Century B.C.), Strabo
(64
B.C.—25 A.D.), and Dioscorides (1st Century A.D.).
Aristotle, apart from occasional mineralogical or metallurgical references in
bilibus,
relation of these to the origin of stones and metals. Agricola was, to a considerable measure,
a follower of this school, and
their views colour much of his writings. We, however, discuss
elsewhereEspecially in
quote largely from Aristotle's There
is a spurious work on stones attributed to Aristotle of some
interest to mineralogists. It was
probably the work of some Arab early in the Middle Ages.
Theophrastus, the principal disciple of Aristotle, appears to have written at
least two
works relating to our subject—one “On
Stones”, and the other on metals, mining or metal
lurgy, but
the latter is not extant. The work “On Stones” was first printed in Venice in
1498,
and the Greek text, together with a fair English translation by Sir John
Hill, was
published in London in 1746 under the title
“Theophrastus on Stones”; the translation is,
however,
somewhat coloured with Hill's views on mineralogy. The work comprises 120
short paragraphs, and would, if reproduced, cover
but about four of these pages. In the
first paragraphs are the Peripatetic view of the origin of stones
and minerals, and upon the
foundation of Aristotle he makes some
modifications. The principal interest in Theophrastus'
work is the description of
minerals; the information given is, however, such as might be
pos
sessed by any ordinary workman, and betrays no particular
abilities for natural philosophy. He enumerates various exterior characteristics, such as colour, tenacity,
hardness, smooth
ness, density, fusibility, lustre, and
transparence, and their quality of reproduction, and then
proceeds to
describe various substances, but usually omits his enumerated
characteristics. Apart from the then known metals and certain “earths” (ochre,
marls, clay, etc.), it is possible
to identify from his descriptions
the following rocks and minerals:—marble, pumice, onyx,
gypsum,
pyrites, coal, bitumen, amber, azurite, chrysocolla, realgar, orpiment,
cinnabar,
quartz in various forms, lapis lazuli, emerald, sapphire,
diamond, and ruby. Altogether there
are some sixteen distinct mineral species. He also describes the touchstone and its uses, the
making of white-lead
and verdigris, and of quicksilver from cinnabar.
Diodorus Siculus was a Greek native of Sicily.
His “historical library” consisted of
some 40 books, of
which parts of 15 are extant. The first print was in Latin, 1472, and in
Greek in 1539; the first
translation into English was by Thomas Stocker, London, 1568, and
later
by G. Booth, 1700. We have relied upon Booth's translation, but with some
amend
ments by friends, to gain more literal statement. Diodorus, so far as relates to our subject,
gives merely the occasional
note of a traveller. The most interesting paragraphs are his
quotation from Agatharchides on
Egyptian mining and upon British tin.
Strabo was also a geographer.
His work consists of 17 books, and practically all
survive. We have relied upon the most excellent translation of Hamilton and Falconer,
London, 1903, the only one in English. Mines and minerals did not escape such an acute
geographer, and the
matters of greatest interest are those with relation to Spanish mines.
Dioscorides was a Greek physician who wrote entirely from the standpoint of
materia
medica, most of his work being devoted to herbs; but Book V. is
devoted to minerals and
rocks, and their preparation for medicinal
purposes. The work has never been translated
into English, and we have relied upon
the Latin translation of Matthioli, Venice, 1565, and notes
upon the
Greek text prepared for us by Mr. C. Katopodes.
In addition to most of the sub
stances known before, he, so far as
can be identified, adds schist,
He describes the making of
certain artificial products, such as copper oxides, vitriol, litharge,
lies in the
processes set out for making his medicines.
Occasional scraps of information relating to the metals or mines in some
connection
are to be found in many other Greek writers, and in
quotations by them from others which are
not now extant, such as
Polybius, Posidonius, etc. The poets occasionally throw a gleam
while the historians, philosophers, statesmen, and physicians, among
them Herodotus,
Xenophon, Demosthenes, Galen, and many others, have
left some incidental references to the
metals and mining, helpful to
gleaners from a field, which has been almost exhausted by time. Even Archimedes made pumps, and Hero surveying instruments for mines.
ROMAN AUTHORS.—Pre-eminent among all ancient writers on these subjects
is, of
course. Pliny, and in fact, except some few lines by Vitruvius, there is practically
little else
in extant Roman literature of technical interest, for the
metallurgical metaphors of the poets
and orators were threadbare by
this time, and do not excite so much interest as upon their
first
appearance among the Greeks and Hebrews.
Pliny (Caius Plinius Secundus) was born 23 A.D., and was killed by eruption
of Vesuvius
79 A.D. His Natural History should be more properly called an encyclopædia, the
whole
comprising 37 books; but only portions of the last four books
relate to our subject, and over
one-half of the material there is upon
precious stones. To give some rough idea of the small
quantity of even this, the most
voluminous of ancient works upon our subject, we have made
an estimate
that the portions of metallurgical character would cover, say, three pages
of
this text, on mining two pages, on building and precious stones
about ten pages. Pliny
and Dioscorides were contemporaries, and while Pliny nowhere
refers to the Greek, internal
evidence is most convincing, either that
they drew from the same source, or that Pliny drew
from Dioscorides. We have, therefore, throughout the text given precedence in time to the
Greek author in matters of historical interest. The works of Pliny were first printed at Venice
in 1469. They have
passed dozens of editions in various languages, and have been twice
translated into English. The first translation by Philemon Holland, London, 1601, is quite
impossible. The second translation, by Bostock and Riley, London, 1855, was a great
advance, and the notes are most valuable, but in general the work has
suffered from a freedom
justifiable in the translation of poetry, but
not in science. We have relied upon the Latin
edition of Janus, Leipzig, 1870. The
frequent quotations in our footnotes are sufficient
indication of the
character of Pliny's work. In general it should be remembered that he was
himself but a compiler of
information from others, and, so far as our subjects are concerned,
of
no other experience than most travellers. When one considers the reliability of such
authors to-day on technical
subjects, respect for Pliny is much enhanced. Further, the text
is no doubt much corrupted through the generations of
transcription before it was set in type. So far as can be identified with any assurance, Pliny adds but few distinct
minerals to those
enumerated by Theophrastus and Dioscorides. For his metallurgical and mining information
we refer to the footnotes,
and in general it may be said that while those skilled in metallurgy
can dimly see in his statements many metallurgical operations, there is
little that does not
require much deduction to arrive at a conclusion. On geology he offers no new philosophical
deductions of consequence; the
remote connection of building stones is practically all that
can be
enumerated, lest one build some assumption of a knowledge of ore-deposits on
the
use of the word “vein”. One point of great interest to this work is that in his search for Latin
terms for technical purposes Agricola relied almost wholly upon Pliny,
and by some devotion
to the latter we have been able to disentangle
some very puzzling matters of nomenclature
in
Vitruvius was a Roman architect of note of the 1st Century B.C.
His work of ten
books contains some very minor references to pumps and
machinery, building stones, and the
preparation of pigments, the latter
involving operations from which metallurgical deductions
can
occasionally be safely made. His works were apparently first printed in Rome in 1496.
There are many
editions in various languages, the first English translation being from the
French in 1692. We have relied upon the translation of Joseph Gwilt,
London, 1875, with
such alterations as we have considered
necessary.
MEDIÆVAL AUTHORS.
For convenience we group under this heading the writers
of interest from
Roman times to the awakening of learning in the early 16th Century.
Apart from Theophilus, they are mostly alchemists; but, nevertheless, some
are of great
importance in the history of metallurgy and chemistry. Omitting a horde of lesser lights
upon whom we have given some data
under the author's preface, the works principally con
cerned are
those ascribed to Avicenna, Theophilus, Geber, Albertus Magnus, Roger Bacon,
and Basil Valentine. Judging from the Preface to
subsidiary works,
Agricola must have been not only familiar with a wide range of alchemistic
material, but also with a good deal of the Arabic literature, which had
been translated into
Latin. The Arabs were, of course, the only race which kept the light of science
burning
during the Dark Ages, and their works were in considerable
vogue at Agricola's time.
Avicenna (980-1037) was an Arabian physician of great note, a translator of
the Greek
classics into Arabic, and a follower of Aristotle to the
extent of attempting to reconcile the
Peripatetic elements with those
of the alchemists. He is chiefly known to the world through
the works which he compiled on
medicine, mostly from the Greek and Latin authors. These
works for centuries dominated the medical world, and were used in
certain European Univer
sities until the 17th century. A great many works are attributed to him, and he is copiously
quoted by
Agricola, principally in his
exposure.
Theophilus was a Monk and the author of a most illuminating work, largely
upon
working metal and its decoration for ecclesiastical purposes. An excellent translation, with
the Latin text, was published by Robert
Hendrie, London, 1847, under the title “An Essay
upon various
Arts, in three books, by Theophilus, called also Rugerus, Priest and
Monk.”
Hendrie, for many sufficient reasons, places the period of
Theophilus as the latter half of the
11th century. The work is mainly devoted to preparing pigments, making glass, and working
metals, and their conversion into ecclesiastical paraphernalia, such as
mural decoration,
pictures, windows, chalices, censers, bells, organs,
etc. However, he incidentally describes
the making of metallurgical furnaces,
cupellation, parting gold and silver by cementation
with salt, and by
melting with sulphur, the smelting of copper, liquating lead from it, and
the
refining of copper under a blast with poling.
Geber was until recent years considered to be an Arab alchemist of a period
somewhere
between the 7th and 12th centuries. A mere bibliography of the very considerable literature
which exists in
discussion of who, where, and at what time the author was, would fill pages.
Those who are interested may obtain a start upon such references from Hermann
Kopp's
träge zur Geschichte der
Chemie,
Glasgow, 1906. Berthelot, in his
the name of Geber were not in the main
of Arabic origin, but composed by some Latin scholar
in the 13th
century. In any event, certain works were, under this name, printed in Latin as
early as 1470-80, and have passed innumerable editions since. They were first translated into
English by Richard Russell, London,
1678, and we have relied upon this and the Nuremberg
edition in Latin
of 1541. This work, even assuming Berthelot's view, is one of the most
important in the history of chemistry and metallurgy, and is
characterised by a directness
of statement unique among alchemists. The making of the mineral acids—certainly nitric and
The author
was familiar with saltpetre, sal-ammoniac, and alkali, and
with the acids he prepared many
salts for the first time. He was familiar with amalgamation, cupellation, the separation of
gold
and silver by cementation with salt and by nitric acid. His views on the primary com
position of bodies dominated the
alchemistic world for centuries. He contended that all
metals were composed of “spiritual”
sulphur (or arsenic, which he seems to consider a special
form of
sulphur) and quicksilver, varying proportions and qualities yielding
different metals. The more the quicksilver, the more “perfect” the metal.
Albertus Magnus (Albert von Bollstadt) was a Dominican Monk, afterwards
Bishop,
born about 1205, and died about 1280. He was rated the most
learned man of his time, and
evidence of his literary activities lies
in the complete edition of his works issued by Pierre
Jammy, Lyons,
1651, which comprises 21 folio volumes. However, there is little doubt that
a great number of works attributed
to him, especially upon alchemy, are spurious. He
covered a wide range of theology, logic, alchemy, and natural
science, and of the latter the
following works which concern our
subject are considered genuine:—
Mineralibus, De Generatione et Corruptione, They are little more than
compilations and expositions of the classics
muddled with the writings of the Arabs, and in
general an attempt to
conciliate the Peripatetic and Alchemistic schools. His position in the
history of science has been greatly over-estimated. However, his mineralogy is, except for
books on gems, the only writing
of any consequence at all on the subject between Pliny and
Agricola,
and while there are but two or three minerals mentioned which are not to be
found
in the ancient authors, this work, nevertheless, deserves some
place in the history of science,
especially as some attempt at
classification is made. Agricola devotes some thousands of
words to the refutation of his
“errors.”
Roger Bacon (1214-1294) was a Franciscan Friar, a lecturer at Oxford, and a
man of
considerable scientific attainments for his time. He was the author of a large number of
mathematical, philosophical, and
alchemistic treatises. The latter are of some importance
in the history of chemistry, but have
only minute bearing upon metallurgy, and this chiefly
as being one of
the earliest to mention saltpetre.
Basil Valentine is the reputed author of a number of alchemistic works, of
which none
appeared in print until early in the 17th century. Internal evidence seems to indicate that
the “Triumphant Chariot
of Antimony” is the only one which may possibly be authentic,
and
could not have been written prior to the end of the 15th or early 16th
century, although
it has been variously placed as early as 1350. To
this work has been accredited the first
mention of sulphuric and
hydrochloric acid, the separation of gold and silver by the use of
antimony (sulphide), the reduction of the antimony sulphide to the
metal, the extraction of
copper by the precipitation of the sulphate
with iron, and the discovery of various antimonial
salts. At the time of the publication of works ascribed to Valentine practically all
these
things were well known, and had been previously described. We are, therefore, in much doubt
as to whether this author really
deserves any notice in the history of metallurgy.
EARLY 16TH CENTURY WORKS.
During the 16th century, and prior to
Metallica,
nology—the
There are also some minor works by the alchemists of some interest
for isolated statements,
particularly those of Paracelsus. The three works mentioned, however, represent such a
Under this title we frequently refer to a little booklet on
veins and
ores, published at the beginning of the 16th century. The title page of our copy is
as below:—
büchlin
von allen Metal
len/als Golt/Silber/Zcyn/Rupfer
erts/
This book is small 8vo, comprises 24 folios without pagination, and has no
typographical
indications upon the title page, but the last line in the
book reads:
Johan
Loersfelt,
1533, by Christian
Egenolph, is entitled
besides the above, an extract and plates from the
recipes for assay tests. All of these booklets, of which we find mention, comprise instructions
from Daniel, a skilled miner, to Knappius, “his mining
boy”. Although the little books of
this title are all anonymous, we are
convinced, largely from the statement in the Preface of Agricola
says: “Two books have been written in our tongue: the one
on the assaying of mineral sub
stances and metals, somewhat
confused, whose author is unknown; the other ‘On Veins’,
of
which Pandulfus Anglus is also said to have written,
by Calbus of Freiberg, a
well-known doctor; but neither of them accomplished the task he had
begun.
an almost verbatim quotation from the Jacobi
Fribergius, so called by Agricola himself, is certainly no other than
the Freiberg doctor,
Rühlein von C(K)albe.” There are also
certain internal evidences that support Agricola's
statement, for the
work was evidently written in Meissen, and the statement of Agricola that
the book was unfinished is borne out by a short dialogue at the end of
the earlier editions,
designed to introduce further discussion. Calbus (or Dr.
Ulrich Rühlein von Kalbe) was a very
active citizen of Freiberg,
having been a town councillor in 1509, burgomaster in 1514, a
mathematician, mining surveyor, founder of a school of liberal arts,
and in general a physician. He died in 1523.
in endeavour to find the date of
its first appearance. Through the courtesy of M. Polain,
who has carefully examined for us the
that it is
similar as regards text and woodcuts to the Erfurt edition, 1527. This copy
in the
Bibliothèque Nationale is without typographical
indications, and M. Polain considers it
very possible that it is the original edition
printed at the end of the fifteenth or begininng of
the sixteenth
centuries. Mr.
Bennett Brough,
first edition was printed at Augsburg in 1505, no copy of which seems
to be extant. The
Librarian at the School of Mines at Freiberg has kindly furnished us
with the following notes
as to the titles of the copies in that
Institution:—(1)
lein,
(1527); (3) the same, Heinrich Steyner, Augsburg,
1534; (4) the same, 1539. On comparing
these various editions (to which
may be added one probably published in Nürnberg by Fried
rich
Peypus in 1532
their contents and
by two entirely different sets of woodcuts.
GROUP I.
Nat.,
(
GROUP II.
There are also others of later date toward the end of the sixteenth
century.
The
with the
words:
Group II.
these words are followed by a short explanation of the signs used in the
woodcuts,
and by directions for colouring the woodcuts, and in some
cases by several pages containing
definitions of some 92 mining terms. In the editions of Group I. the woodcut on the title page
represents a
miner hewing ore in a vein and two others working a windlass. In those of
Group II. the woodcut on the title page represents one miner
hewing on the surface, another to
the right carting away ore in a
handcart, and two others carrying between them a heavy
timber. In our opinion Group I. represents the older and original work of Calbus; but
as we
have not seen the copy in the
so far been traced to Veith's catalogue,
settled at present. In any event, it appears that the material grafted on in the second group
was later, and by various authors.
The earliest books comprise ten chapters, in which Daniel delivers about
6,000 words
of instruction. The first four chapters are devoted to the description of veins and the
origin
of the metals, of the remaining six chapters one each to silver,
gold, tin, copper, iron,
lead, and quicksilver. Among the mining terms are explained the meaning of country rock
(
and outcrop
(
the other of the Various veins are illustrated, and also
for the first time a mining
compass. The account of the origin of the metals is a muddle
of the Peripatetics,
the alchemists, and the astrologers, for which acknowledgment to Albertus
Magnus is given. They are represented to originate from quicksilver and sulphur through
heat, cold, dampness, and dryness, and are drawn out as exhalations
through the veins, each
metal owing its origin to the special influence
of some planet; the Moon for silver, Saturn for
lead, etc. Two types of veins are mentioned, “standing” (
gang
wall, and other varieties. Prominence is also given to the
ated upon, and veins of east-west strike lying upon a south
slope are considered the best. From the following notes it will be seen that two or three other types of
deposits besides veins
are referred to.
In describing silver veins, of peculiar interest is the mention of the
association of bismuth
(
spar
(
materials, “according to the mingling of the
various vapours.” The term
but it is difficult to say if silver
glance is meant; if so, it is the first mention of this mineral. So far as we know, this is the first use of any of the terms in print.
Gold alluvial is described,
part of the gold being assumed as generated
in the gravel. The best alluvial is in streams
running east and west. The association of gold with pyrites is mentioned, and the pyrites is
found “in some places as a complete stratum carried through
horizontally, and is called a
of the heavens can be but
little completed on account of the unsuitability of the position.”
Gold pyrites that comes in veins is better. Tin is mentioned as found in alluvial, and also in
veins, the latter
being better or worse, according to the amount of pyrites, although the
latter
can be burned off. Tin-stone is found in masses, copper ore in schist and in veins sometimes
with pyrites. The ore from veins is better than schist.
Iron ore is found in masses, and
sometimes in veins; the latter is the
best. “The iron veins with good hanging-and foot
walls are not to be
despised, especially if their strike be from east to west, their dip to the
south, the foot-wall and outcrop to the north, then if the ironstone is
followed down, the
vein usually reveals gold or other valuable
ore”. Lead ore is found in
and Quicksilver, like other ore, is sometimes found in brown earth, and
sometimes, again, in caves where it has run out like water. The classification of veins is the
same as in
opposition, for the quotations are given in order to be
demolished.
Agricola refers in the Preface of
on assaying
and refining metals, and it is our belief that it was to some one of the
little assay
books published early in the 16th century. There are several of them, seemingly revised
editions of each other; in
the early ones no author's name appears, although among the
later
editions various names appear on the title page. An examination of these little books
discloses the fact that their main
contents are identical, for they are really collections of
recipes
after the order of cookery books, and intended rather to refresh the memory
of those
lein/auff Bold/Silber/tupffer/
vnd Sley/Unch allerlay Metall
wie mandie zů nus arbayten
Probierenſoll.
werc
ſamengebracht.The books appear to have grown by accretions
from many sources, for a
large number of methods are given over and over again in the same
book
with slight variations. We reproduce the title page of our earliest copy.
The following is a list of these booklets so far as we have been able to
discover actual
copies:—
As mentioned under the
contains only a portion of the Ferguson
Freiberg School of Mines Catalogue gives also Frankfort,
1608, and Nürnberg, 1706. The
British Museum copy of earliest
date, like the title page reproduced, contains no date. The
title page woodcut, however, in the Museum copy is referred from
that above, possibly indi
cating an earlier date of the Museum
copy.
The booklets enumerated above vary a great deal in contents, the successive
prints
representing a sort of growth by accretion. The first portion of our earliest edition is devoted
to weights, in
which the system of “lesser weights” (the principle of the
“assay ton”) is
explained. Following this are exhaustive lists of touch-needles of various composition.
Directions are given with regard to assay furnaces, cupels, muffles,
scorifiers, and crucibles,
granulated and leaf metals, for washing,
roasting, and the preparation of assay charges. Various reagents, including glass-gall, litharge, salt, iron filings, lead,
“alkali”, talc, argol,
saltpetre, sal-ammoniac, alum,
vitriol, lime, sulphur, antimony,
wasser,Various assays are described and directions given for crucible,
scorification, and cupellation tests. The latter part of the book is devoted to the refining
and parting of
precious metals. Instructions are given for the separation of silver from iron,
from
lead, and from antimony; of gold from silver with antimony (sulphide) and
sulphur, or
with sulphur alone, with “
with sulphur and with lead. The amalgamation of gold and silver is mentioned.
The book is diffuse and confused, and without arrangement or system, yet a
little
consideration enables one of experience to understand most
statements. There are over 120
recipes, with, as said before, much repetition; for
instance, the parting of gold and silver
by use of sulphur is given
eight times in different places. The final line of the book is: “Take
this in good part, dear
reader, after it, please God, there will be a better.” In truth,
however,
there are books on assaying four centuries younger that are
worse. This is, without doubt,
the first written word on assaying, and it
displays that art already full grown, so far as con
cerns gold and
silver, and to some extent copper and lead; for if we eliminate the words
dependent on the atomic theory from modern works on dry assaying, there
has been but very
minor progress. The art could not, however, have reached this advanced stage but by slow
accretion, and no doubt this collection of recipes had been handed from
father to son long
before the 16th century. It is of wider interest that these booklets represent the first milestone
on the road to quantitative analysis, and in this light they have been
largely ignored by the
historians of chemistry. Internal evidence in Book VII. of
the reference in
the Preface, leave little doubt that Agricola was familiar with these
book
lets. His work, however, is arranged more systematically, each operation stated
more clearly,
with more detail and fresh items; and further, he gives
methods of determining copper and
lead which are but minutely touched
upon in the
bismuth,
quicksilver, and iron are entirely new.
Biringuccio (Vanuccio). We practically know nothing about this author.
From the
preface to the first edition of his work it appears he was
styled a mathematician, but in the
text^{14} he certainly states that
he was most of his time engaged in metallurgical operations,
and that
in pursuit of such knowledge he had visited Germany. The work was in Italian,
published at Venice in 1540, the title page of
the first edition as below:—
It comprises ten chapters in 168 folios demi-octavo.
Other Italian editions of which
we find some record are the second at
Venice, 1552; third, Venice, 1558; fourth, Venice,
1559: fifth,
Bologna, 1678. A French translation, by Jacques Vincent, was published in
Paris, 1556, and this translation was again published at Rouen in 1627.
Of the ten chapters the
last six are almost wholly devoted to metal
working and founding, and it is more largely for
this description of
the methods of making artillery,
is celebrated. In any event, with the exception of a quotation which we give on page 297 on
silver amalgamation, there is little of interest on our subject in the
latter chapters. The
first four chapters are undoubtedly of importance in the history of
metallurgical literature,
and represent the first work on smelting. The descriptions are, however, very diffuse, difficult
to follow, and
lack arrangement and detail. But like the
written prior to The ores of gold, silver, copper, lead, tin, and iron are described, but much
interrupted with
denunciations of the alchemists. There is little of geological or mineralogical interest, he too
holding
to a muddle of the classic elements astrology and alchemy. He has nothing of con
sequence to say on mining, and dismisses
concentration with a few words. Upon assaying
his work is not so useful as the On ore smelting he describes the reduction
of iron and lead ores and
cupriferous silver or gold ores with lead. He gives the barest
description of a blast furnace, but adds an
interesting account of a He
describes liquation as consisting of one operation; the subsequent
treatment of the copper
by refining with an oxidising blast, but does
not mention poling; the cupellation of argen
tiferous lead and the
reduction of the litharge; the manufacture of nitric acid and that
method of parting gold and silver. He also gives the method of parting with antimony and
sulphur, and by
cementation with common salt. Among the side issues, he describes the
method of making brass with
calamine; of making steel; of distilling quicksilver; of melting
out
sulphur; of making vitriol and alum. He states that
gallio
In general, Biringuccio should be accredited with the first description (as
far as we
are aware) of silver amalgamation, of a reverberatory
furnace, and of liquation, although the
description is not complete. Also he is, so far as we are aware, the first to mention cobalt
blue
(His descriptions
are far inferior to Agricola's; they do not compass
anything like the same range of metal
lurgy, and betray the lack of
a logical mind.
There are several works devoted to mineralogy, dating from the fifteenth
and early sixteenth centuries, which were, no doubt, available to
Agricola in the compilation of
his They are, however, practically all compiled from the jeweller's point
of view rather than from that of the miner. Among them we may mention the poem on
precious stones by Marbodaeus, an
author who lived from 1035 to 1123, but which was first
printed at
Vienna in 1511;
first printed in Venice in 1502. A work of wider interest to
mineralogists is that by Christoph
Entzelt (or Enzelius, Encelio,
Encelius, as it is variously given), entitled
and first printed in 1551. The
work is five years later than
much new material
and was available to Agricola prior to his revised editions.
WEIGHTS AND MEASURES.
As stated in the preface, the nomenclature to be adopted for weights and
measures
has presented great difficulty. Agricola uses, throughout, the Roman and the Romanized
Greek scales, but
in many cases he uses these terms merely as lingual equivalents for the
German quantities of his day. Moreover the classic language sometimes failed him, where
upon he
coined new Latin terms adapted from the Roman scale, and thus added further
confusion. We can, perhaps, make the matter clearer by an illustration of a case in
weights.
The Roman
and the
English hundredweight of 112 pounds can be called lingual equivalents. The first
weighs about 494,600 Troy grains, the second 721,900, and the
third 784,000. While the
divisions of the
and the
the author had in mind the
Roman ratios. However, on p.
509 he makes the direct statement
that the If we take an example such as “each
pondium
lents, we should
find that it runs 24.3 Troy ounces per short ton, on the basis of Roman
values, and 18.25 ounces per short ton, on the basis of old German. If we were to trans
late these into English lingual equivalents of
one ounce per hundredweight, then the value
would be 17.9 ounces per
short ton.
Several possibilities were open in translation: first, to calculate the
values accur
ately in the English units; second, to adopt the
nearest English lingual equivalent; third,
to introduce the German
scale of the period; or, fourth, to leave the original Latin in the
text. The first would lead to an indefinite number of decimals and to constant
doubt as to
whether the values, upon which calculations were to be
based, were Roman or German. The
second, that is the substitution of lingual equivalents, is
objectionable, not only because
it would indicate values not meant by
the author, but also because we should have, like
Agricola, to coin new
terms to accommodate the lapses in the scales, or again to use decimals.
In the third case, that is in the use of the old German scale, while it would
be easier to adapt
than the English, it would be more unfamiliar to
most readers than the Latin, and not so
expressive in print, and
further, in some cases would present the same difficulties of
cal
culation as in using the English scale. Nor does the contemporary German translation of
Re Metallica
quence
the summation of his weights often gives incorrect results. From all these possibilities
we have chosen the fourth, that is simply
to reproduce the Latin terms for both weights and
measures. We have introduced into the footnotes such reductions to the English scale as
we
considered would interest readers. We have, however, digressed from the rule in two cases,
in the adoption
of “foot” for the Latin Apart from the fact
that these were not cases where accuracy is
involved, Agricola himself explains (p. 77)
that he means the German values for these particular terms, which,
fortunately, fairly closely
approximate to the English. Further, we have adopted the Anglicized words “digit”,
“palm”, and “cubit”, instead of their Latin
forms.
For purposes of reference, we reproduce the principal Roman and old German
scales,
in so far as they are used by Agricola in this work, with their
values in English. All students
of weights and measures will realize that these values are
but approximate, and that this is
not an occasion to enter upon a
discussion of the variations in different periods or by different
authorities. Agricola himself is the author of one of the standard works on Ancient
Weights
and Measures (see Appendix A), and further gives fairly
complete information on contem
porary scales of weight and fineness
for precious metals in Book VII. p. 262 etc., to which
we refer readers.
ROMAN SCALES OF WEIGHTS.
SCALE OF FINENESS
(AGRICOLA'S ADAPTATION).
OLD GERMAN SCALE OF WEIGHTS.
SCALE OF FINENESS.
ROMAN LONG MEASURE.
Also
GREEK LONG MEASURE.
OLD GERMAN LONG MEASURE.
Also
ROMAN LIQUID MEASURE.
(Agricola nowhere uses the Saxon liquid measures, nor do they fall into units
comparable
with the Roman).
NOTE.—The numbers in heavy type refer to the Text;
those in plain
type to the Footnotes, Appendices, etc.