Although he was not strictly an occult philosopher, the work of Georgius Agricola exemplifies the practical utility of alchemical and natural historical studies, and the propagation of one technology, that of mining, through the medium of another, the printed book illustrated with woodcuts. Like his contemporary, the great anatomist Andreas Vesalius, Agricola was a humanist physician who observed and experimented for himself, and then used printing to disseminate his findings. In the context of this class, however, it should also be mentioned that Agricola gave considerable credence to the stories of miners about the little spirits to be met with underground [see Maxwell-Stuart source book, p.40].
Georg Bauer was born in Glauchau, in Saxony. He matriculated at Leipzig University in 1514, received his BA in 1515, and then taught Latin and Greek for a few years. In 1517, he was chosen as ludi moderator and in 1519 as rector extraordinarius at the school at Zwickau. In 1523, he returned to Leipzig to study medicine under Heinrich Stromer von Auerbach. To support him during his second period of study he was endowed with a prebend of the St. Erasmus altar for three years by the council of Zwickau. He studied in Bologna, Venice, and probably Padua, and is said to have returned to Germany with an MD. During his time at Bologna and Venice, he served as a member of the editorial staff for the Aldine Press editions of Galen and Hippocrates.
In 1527-30, he was elected town physician and apothecary of St. Joachimstal in Bohemia, an important silver mining centre. In 1533, he moved to Chemnitz, another important mining centre, as town physician. His knowledge of mining allowed him to speculate in mining shares, which he did with great success. By 1542, he is said to have been one of the twelve richest inhabitants of Chemnitz.
"Lapis judaicus. . . usually occurs in the form of symmetrical acorns. Prominent lines run from the blunt to the pointed end and these are so regular they appear to have been made in a lathe and resemble the striae on a shell. The people who call this mineral pyren liken these lines to the bones of a fish that extend from the back down to the belly. . . When split open it is light inside and glistens like marble and in some cases the outside also has a high lustre."
"Certain rocks, when split open, are found to contain shells; for example, the conchites beds of Megara and the rocks of France. . . Ostracites is a stone that takes its name from ostreum [oyster] which it resembles. There are two species, the larger found in the moat on the north side of Hildesheim. . . The smaller species is found not far from Hanover on a cliff near the village of Linda in an unctuous light green earth. . . It forms in strata that are conspicuous. When tapped with the finger it has the sound of a jug."
Agricola noted the resemblance of many of his "fossils"
to living organisms, but rarely stated that any of
his fossils actually did represent once-living organisms.
He rejected many popular beliefs but listed the magical and medicinal uses
to which rocks, minerals and fossils were put: powdered lapis judaicus
(the blastoid echinoderm Pentremites) was prescribed for kidney stones,
while ostreites (fossil oyster shell), moistened with water, "reduces
inflammation of the breasts, heals ulcers and is poisonous to crawling
insects."
Selected images of mining machinery from De Re Metallica, in PDF files; click on icons for explanation
Ore
hoist To remove
ore from the mine; simple windlass with
handcranks lowers and raises ore buckets on a rope in a
vertical mining shaft.
Agricola, 161
Water
hoist To remove water from the mine;
endless chain of water
dippers in a vertical shaft, manually powered by a treadmill.
Agricola, 174
Sump
pump To remove water from the mine; hand-operated
sump
pump for a vertical shaft
Agricola, 177
Ventilating fan To ventilate mine shafts; three hand and wind operated fans Agricola, 205
Ventilating bellows To ventilate mine shafts; hand operated Agricola, 209
Assay
furnace To smelt small samples of metal ore for purposes
of
assaying, (determining the amount of metal in the ore)
Agricola, 223
Bellows
for assay furnace To provide a blast
of air to raise the
temperature of the assay furnace
Agricola, 227
Crushing
gold and silver ore Cottage setting for manual hammering
to break up gold and silver ore for smelting
Agricola, 270
Crushing
roasted ore In Westphalia, Germany, miners
roast ore, then
break up the ore with hammers on a stone pavement Agricola,
272
Roasting
ore Variety of methods for roasting ore to
remove sulphur and
other impurities
Agricola, 277
Stamping
mill Stamping mill for crushing ore into smaller pieces,
powered
by a water wheel
Agricola, 284
Making Stamps Workers make parts of stamps before assembly Agricola, 285
Sieves
Workers use different sieves to separate ore into different
crushing sizes
Agricola, 289
Grinding
mill A mill, powered by a water wheel, constructed to grind
copper or tin ore into a power, similar to a grain grinding mill
Agricola, 294
Power
for grinding mill Four kinds of power
are depicted: wind, water,
animal, human.
Agricola, 296
Gold
separation tubs
Powered, mechanical wash tubs to separate gold
from its ore with quicksilver (mercury)
Agricola, 299
Roasting
tin In preparation for smelting (at high
temperatures), tin-stone
is "roasted" at lower temperature. This burns off impurities.
Agricola, 349
Roasting
copper "cakes" Copper ore heated can produce a cake-like
mass of
copper and substances like alum and saltpetre. These
must be removed before smelting. To remove them,
the cakes are roasted in open pits.
Agricola, 350
Smelters, front view Front view of smelting furnaces Agricola, 357
Smelters,
cut-away view Smelters, with water trough exposed, forehearths,
and doors and tap-holes indicated
Agricola, 358
Smelters,
bellows for blast
View of back side of smelter furnace building,
with water-powered bellows shown
Agricola, 359
Making
furnace liner, "lute", for smelters Furnace liner,
"lute", for the smelter
is made from ash and earth
Agricola, 377
Smelter
and alloy
The smelter pours alloy out of the smelting furnace,
while another worker pours the allow into a mould.
Agricola, 383
Making
steel out of iron At a forge or a furnace, with bellows
for blast,
the smith makes steel out of iron.
Agricola, 425
Separating
gold from impurities In a gold shop, gold is separated
from
impurities by heating the ore with reagents.
Agricola, 442
Separating
silver from lead Lead and mercury and other "fluxes" used
to separate
silver and/or gold from ore were poisonous. Smelters
had to take precautions to avoid fumes from crucibles
and furnaces. Here, lead is being used to separate silver.
The foreman eats butter to protect against fumes.
Agricola, 474
Plan for gold smelting house The building is over 264 feet long and 70 feet wide. Agricola, 493
Agricola, De Re Metallica, trans. Herbert Clark Hoover and Lou Henry Hoover, 1912 (Pbk. reprint, New York, 1950)
Agricola, De Natura Fossilium, trans. Mark Chance Bandy and Jean A. Bandy, Geological Society of America, Special Paper 63 (1955)
Marco Beretta, "Humanism and chemistry : the spread of Georgius Agricola's metallurgical writings", Nuncius 12/1 (1997) 17-47
Owen Hannaway, "Reading the pictures : the context of Georgius Agricola's woodcuts", Nuncius 12/1 (1997) 49-66
Marco Beretta, The Enlightenment of Matter: The Definition of Chemistry from Agricola to Lavoisier (Nantucket, Mass., 1993)
Owen Hannaway, "Georgius Agricola as humanist", Journal of the History of Ideas 53 (1992) 553-560
Owen Hannaway, "Herbert Hoover and Georgius Agricola: The distorting mirrors of history", Bulletin for the History of Chemistry 12 (1992) 3-10 [ND library holdings of this journal start in 1994]
Alan J. Rocke, "Agricola, Paracelsus, and 'chymia' ",
Ambix
32 (1985) 38-45