Aurichalcum, or golden copper—that is, brass—was well known to the early workers in copper, and was made in Pliny’s time by heating together copper, cadmia (calamine), and charcoal.
Bell metal was employed by the Assyrians, and bronze was cast by the Egyptians for the manufacture of mirrors, vases, shields, etc., as far back as 2000 B.C. Statuary bronze, largely used by the Romans, usually contained more or less lead.
Tin, which was also known to the early Egyptians, would appear to have been first obtained from the East Indies, and to have been known under the Sanscrit name of Kastîra (Kâs, to shine), whence we have the Arabic word for tin, Kàsdir, and the Greek κασσίτερος, used by Homer and Hesiod. Tin ores are found in Britain (Cornwall), and were brought thence by the Phœnicians. The group of islands, including the Scilly Islands and the larger island to the east (Britain), was known to the Romans as the Insulæ Cassiterides.
Pliny states that the tin is found in grains in alluvial soil, from which it is obtained by washing; but he gives no description of the method of smelting. The Latin word for tin was stannum; it was also known as plumbum album, in contradistinction to lead, which was called plumbum nigrum. Tin was used by the Romans for covering the inside of copper vessels, and was also occasionally employed in the construction of mirrors.
Lead was well known to the Egyptians. In Pliny’s time it was mainly procured from Spain and from Britain (Derbyshire). Leaden pipes were used by the Romans for the conveyance of water, and sheet lead was employed by them for roofing purposes. The Romans were also aware of alloys of lead and tin. Argentarium was composed of equal parts of lead and tin; tertiarium, used as a solder, consisted of two parts of lead and one part of tin.
Iron, although now the most important of the common metals, was not in general use until long after the discovery of gold, silver, and copper. This was probably due to the fact that, although its ores are relatively abundant and widely distributed, its extraction as a metal demanded greater skill and more appliances than were possessed by the earlier races. Metallic iron was, however, well known to the Egyptians, who employed it in the manufacture of swords, knives, axes, and stone-chisels, both as malleable iron and as steel. Steel was also known to the Chinese as far back as 2220 B.C., and they were acquainted with the methods of tempering it. The good quality of Chinese steel caused it to be highly prized by Western nations. The earliest people to smelt iron are supposed to have been the Chalybes, a nation inhabiting the neighbourhood of the Black Sea; it is from them that the ancient name for steel—chalybs—is derived, and also our word “chalybeate.”
Mercury has long been known, but there is no evidence that the ancient Egyptians were aware of its existence, or it would probably have been mentioned by Herodotus. It was familiar to Aristotle, and its mode of manufacture from cinnabar is described by Theophrastus (320 B.C.), who terms it “liquid silver.” Processes of amalgamation were known to Pliny, who notes the readiness with which mercury dissolves gold. Pliny appears to distinguish the native metal found in Spain, which he terms argentum vivum (quicksilver), from that obtained by sublimation or distillation from cinnabar, which he calls hydrargyrum, from which we get the chemical symbol for mercury Hg.
A considerable number of metallic compounds were known to the ancients, and were employed by them as medicines and as pigments. The oxides of copper, known as flos æris, and scoria æris, obtained by heating copper bars to redness and exposing them to air, were used as escharotics. Verdigris, or ærugo, was made by the same methods as now. Blue vitriol, or chalcantum, is described by Pliny, who says that the blue transparent crystals are formed on strings suspended in its solution.
Chrysocolla, malachite, or copper carbonate, was used as a green pigment. The blue κύανος of the Greeks, or cœruleum of the Romans, was obtained by fritting together alkali, sand, and oxide of copper. Botryitis, placitis, onychitis, ostracitis, were varieties of cadmia or oxide of zinc, obtained by calcining calamine, and were used in the treatment of ulcers, etc. Molybdena, which was the Latin name for litharge, was employed externally as an astringent and in the manufacture of plaster. The lead plaster employed by Roman surgeons was practically identical in character and mode of preparation with that in use to-day. Cerussa, or white lead, was made as now by exposing sheets of lead to the fumes of vinegar. It was used in medicine, as a pigment, and in the preparation of cosmetics. Cerussa usta was probably red lead. Its present name of minium was originally applied to cinnabar, the red sulphide of mercury, which was frequently adulterated with red lead.
Cinnabar, formerly obtained from Africa, and, by the Romans, from Spain, was also used externally in medicine, and was a highly prized pigment, whose value was known to the Chinese from very early times. The black sulphide of antimony, the stimmi and stibium of Dioscorides and Pliny, was employed by women in Asia, Greece, and latterly in Western Europe, and is still so used in the East, for blackening their eyelashes. Preparations of antimony were used in medicine. Realgar, the scarlet sulphide of arsenic, the sandarach of Aristotle, and the arrenichon of Theophrastus, was employed as a pigment, and also in medicine, both internally and externally. The yellow sulphide of arsenic or auri pigmentum (orpiment), was also used for the same purposes.