. 
THE BIRTH OF CHEMISTRY 
IV. 
Iron, lead, quicksiluer.—Colours used for painting and dyeing.— 
Glass. —Certain minerals known to the ancients. —Miscellaneous 
processes.—Association of the seven metals with the seven greater 
heavenly bodies.— Conseguent jintroduction of symbols into the 
history of matter. 
[RON was not in common use till long after the introduction of 
copper. It is far more difficult to procure, because it is not met 
with in the native state, and the fusing point is very high. The 
metallurgy of iron is more complex than that of copper, and 
when obtained it is a more difficult metal to work. According 
to Xenophon the melting of iron ore was first practised by the 
Chalubes, a nation dwelling near the Black Sea, hence the name 
Chalups (x@Av) used for steel, and hence our word Chalydeate 
applied to a mineral water containing iron. Steel was known to 
the ancients, but we do not know by what means it was pre- 
pared ; it was tempered by heating to redness, and plunging in 
cold water. According to some, kuanos (vavos) mentioned by 
Homer was steel ; but Mr. Gladstone prefers to conclude that it 
was bronze. Iron was known at least 1537 B.c. It was coined 
into money by the Lacedzemonians, and in the time of Lukourgos 
was incommon use. It was used in the time of Homer for 
certain cutting-instruments, such as woodmen’s axes, and for 
ploughshares. Its value is shown by the fact that Achilles pro- 
posed a ball of iron as a prize for the games in honour of 
Patroklos. Neither iron money nor iron implements of great 
antiquity have been found, because, unlike the other metals of which 
we have spoken above, iron rusts rapidly, and comparatively soon 
disappears. No remains of it have been found in Egypt, yet 
Herodotus tells us that iron instruments were used in building 
Fic. 3-—Egyptian Bellows. 
Vifteenth Century n.c. 
the pyramids ; moreover, steel must have been employed to 
engrave the granite and other hard rocks, massive pillars of 
which are often found engraved most delicately from top to 
bottom with hieroglyphics. Again, the beautifully engraved 
Babylonian cylinders and Egyptian gems, frequently of cornelian 
and onyx, must have required steel tools of the finest temper. 
We have no record of the furnaces in which iron ore was smelted, 
but we know that bellows were in use inthe 15th century B.c. in 
Egypt, and some crucibles of the same period are preserved in 
the Berlin Museum. They closely resemble the crucibles in use in 
the present day. The accompanying woodcut (Fig. 3) represents 
a double pair of bellows, a furnace, fuel, and above perhaps a 
crucible. 
The native Indians prepare iron from hzmatite at the present 
time by equally primitive bellows, which indeed resemble the 
above very closely, and which, without doubt, have been un- 
altered for centuries. A small furnace, A (see the accompanying, 
section, Fig. 4),* is rapidly constructed of clay, and into 
the bottom of this two nozzles, B, are introduced; these are 
connected with the bellows by bamboo tubes. The bellows, 
Cc, consist of cup-shaped bowls of wood covered with goat- 
skin above, and connected with the bamboo below. In the 
centre of the goat-skin cover a round hole is cut; the blower 
places his heel upon this, which is thus closed, while at the same 
time the skin is depressed and a blast is driven from the tube, 
then he steps upon the second skin, and thus a continual blast is 
keptup. The bent bamboo and string, D, is for the purpose of 
raising the goatskin cover of the bellows after depression, which, 
* We are indebted to Dr. Percy for permission to copy this figure from his 
“ Metallurgy,” and to Mr. Murray for the other woodcuts. 
it will be noticed, is accomplished in the Egyptian bellows b' 
string raised by the hand. A piece of hematite is introduced — 
with some charcoal, and after the lapse of some time, it isreduced — 
by the carbonic oxide to a spongy mass of iron. Undoubted 
a crude furnace and appliance of this nature was used by the 
first smelters of iron. . 
Although we hear less of lead than of the preceding metals, — 
it was known to the Egyptians at ‘an early date, and it is men- 
tioned by Homer. In the time of Pliny leaden pipes were used — 
to convey water ; and sheet lead was employed for roofing pur- 
poses, The chief supply of the metal came from a and’ 
Britain. Pliny believed that lead was reproduced in the mine, 
so that if an exhausted mine were closed it would be fit to work - 
again in a few years’ time. This idea of the growth of the 
metals was very generally accepted by the alchemists. Tin and 
lead were sometimes alloyed together by the ancients, and tin — 
was used as a solder for lead. Litharge, or protoxide of lead, — 
and cerussa usta (burnt ceruss), or red lead, were used by painters. - 
Cerussa, which we now call ‘‘white lead,” or more strictly, 
carbonate of lead, was prepared by exposing sheets of lead to” 
the fumes of vinegar in a warm place, a heap of decomposing 
manure for instance. A basic acetate of lead is formed by this — 
means, which is partially converted into carbonate by the carbonic 
acid given off by the decomposing organic matter. Cerussa was 
used by Athenian ladies as a cosmetic. Cerussa usta was first 
formed accidentally from cerussa during the burning of a house ~ 
near the Pirseus. Litharge is easily formed by heating lead above — 
its melting point in air, when it absorbs oxygen gas, and the — 
resulting oxide may be skimmed off. b 
Mercury was common in the time of Pliny, but it is not men- — 
tioned by earlier writers. It was found native in Spain, but was 
more generally obtained by heating cinnabar (sulphide of mercury) 
Tic. 4.—Smelting Furnace and Bellows used by native Indiansin the 
present day, ‘ 
with iron filings in an earthen vessel, to the top of which a cover _ 
was luted. The iron decomposed the sulphide, and the liberated 
mercury was volatilised and condensed on the cover of the — 
vessel, whence it was collected. This method, described by — 
Dioscorides, is the first crude example of d/sté//ation, which after- 
wards became a principal operation among the alchemists and 
chemists for separating the volatile from the fixed. Inthetime 
of Dioscorides cinnabar was called wnium, but it became so— 
largely adulterated with red lead that the term minium was ulti- 
mately applied to the latter. Minium is still one of the names — 
for red lead. Pliny was acquainted with the high specific gravity _ 
of mercury, and with its power of dissolving gold. Substances 
were sometimes gilded by a gold amalgam. Mercury was also 
used, as now, for extracting gold from its earthy matrix ; the gold- _ 
bearing rock was powdered and shaken up with mercury, which 
dissolved out the gold ; the amalgam of gold and mercury was 
then squeezed through leather, which separated most of the mer- _ 
cury ; the solid amalgam was heated to expel the mercury, and — 
pure gold remained. Vitruvius states that gold was recovered 
from gold embroidery by burning the cloth in an earthen pot, — 
and throwing the ashes into water to which quicksilver was 
added, :The latter attracted the gold and dissolved it ; the amal- _ 
gam was put intoa piece of cloth and squeezed between the 
hands, and the mercury, on account of its fluidity, was forced 
through the pores of the cloth, while the gold remained. 
Native mercury was called argentum vivum (quicksilver), — 
while mercury distilled from cinnabar was called hydrargyrum 
