The History of Chemistry. Thomas Thomson
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The only one of these works that I have read with care, is Kerkringius’s translation and commentary on the Currus triumphalis Antimonii. It is an excellent book, written with clearness and precision, and contains every thing respecting antimony that was known before the commencement of the 19th century. How much of this is owing to Kerkringius I cannot say, as I have never had an opportunity of seeing a copy of the original German work of Basil Valentine.
Basil Valentine, like Isaac Hollandus, was of opinion that the metals are compounds of salt, sulphur, and mercury. The philosopher’s stone was composed of the same ingredients. He affirmed, that there exists a great similarity between the mode of purifying gold and curing the diseases of men, and that antimony answers best for both. He was acquainted with arsenic, knew many of its properties, and mentions the red compound which it forms with sulphur. Zinc seems to have been known to him, and he mentions bismuth, both under its own name, and under that of marcasite. He was aware that manganese was employed to render glass colourless. He mentions nitrate of mercury, alludes to corrosive sublimate, and seems to have known the red oxide of mercury. It would be needless to specify the preparations of antimony with which he was acquainted; scarcely one was unknown to him which, even at present, exists in the European Pharmacopœias. Many of the preparations of lead were also familiar to him. He was aware that lead gives a sweet taste to vinegar. He knew sugar of lead, litharge, yellow oxide of lead, white carbonate of lead; and mentions that this last preparation was often adulterated in his time. He knew the method of making green vitriol, and the double chloride of iron and ammonia. He was aware that iron could be precipitated from its solution by potash, and that iron has the property of throwing down copper. He was aware that tin sometimes contains iron, and ascribed the brittleness of Hungarian iron to copper. He knew that oxides of copper gave a green colour to glass; that Hungarian silver contained gold; that gold is precipitated from aqua regia by mercury, in the state of an amalgam. He mentions fulminating gold. But the important facts contained in his works are so numerous, while we are so uncertain about the genuineness of the writings themselves, that it will scarcely be worth while to proceed further with the catalogue.
Thus I have brought the history of alchymy to the time of Paracelsus, when it was doomed to undergo a new and important change. It will be better, therefore, not to pursue the history of alchymy further, but to take up the history of true chemistry; and in the first place to endeavour to determine what chemical facts were known to the Ancients, and how far the science had proceeded to develop itself before the time of Paracelsus.
CHAPTER II.
OF THE CHEMICAL KNOWLEDGE POSSESSED BY THE ANCIENTS.
I
Notwithstanding the assertions of Olaus Borrichius, and various other writers who followed him on the same side, nothing is more certain than that the ancients have left no chemical writings behind them, and that no evidence whatever exists to prove that the science of chemistry was known to them. Scientific chemistry, on the contrary, took its origin from the collection and comparison of the chemical facts, made known by the practice and improvement of those branches of manufactures which can only be conducted by chemical processes. Thus the smelting of ores, and the reduction of the metals which they contain, is a chemical process; because it requires, for its success, the separation of certain bodies which exist in the ore chemically combined with the metals; and it cannot be done, except by the application or mixture of a new substance, having an affinity for these substances, and capable, in consequence, of separating them from the metal, and thus reducing the metal to a state of purity. The manufacture of glass, of soap, of leather, are all chemical, because they consist of processes, by means of which bodies, having an affinity for each other, are made to unite in chemical combination. Now I shall in this chapter point out the principal chemical manufactures that were known to the ancients, that we may see how much they contributed towards laying the foundation of the science. The chief sources of our information on this subject are the writings of the Greeks and Romans. Unfortunately the arts and manufactures stood in a very different degree of estimation among the ancients from what they do among the moderns. Their artists and manufacturers were chiefly slaves. The citizens of Greece and Rome devoted themselves to politics or war. Such of them as turned their attention to learning confined themselves to oratory, which was the most fashionable and the most important study, or to history, or poetry. The only scientific pursuits which ever engaged their attention, were politics, ethics, and mathematics. For, unless Archimedes is to be considered as an exception, scarcely any of the numerous branches of physics and mechanical philosophy, which constitute so great a portion of modern science, even attracted the attention of the ancients.
In consequence of the contemptible light in which all mechanical employments were viewed by the ancients, we look in vain in any of their writings for accurate details respecting the processes which they followed. The only exception to this general neglect and contempt for all the arts and trades, is Pliny the Elder, whose object, in his natural history, was to collect into one focus, every thing that was known at the period when he lived. His work displays prodigious reading, and a vast fund of erudition. It is to him that we are chiefly indebted for the knowledge of the chemical arts which were practised by the ancients. But the low estimation in which these arts were held, appears evident from the wonderful want of information which Pliny so frequently displays, and the erroneous statements which he has recorded respecting these processes. Still a great deal may be drawn from the information which has been collected and transmitted to us by this indefatigable natural historian.
I.—The ancients were acquainted with SEVEN METALS; namely, gold, silver, mercury, copper, iron, tin, and lead. They knew and employed various preparations of zinc, and antimony, and arsenic; though we have no evidence that these bodies were known to them in the metallic state.
1. Gold is spoken of in the second chapter of Genesis as existing and familiarly known before the flood.
“The name of the first is Pison; that is it which encompasseth the whole land of Havilah, where there is gold. And the gold of that land is good: there is bdellium and the onyx-stone.” The Hebrew word for gold, בהז (zahav) signifies to be clear, to shine; alluding, doubtless, to the brilliancy of that metal. The term gold occurs frequently in the writings of Moses, and the metal must have been in common use among the Egyptians, when that legislator led the children of Israel out of Egypt.28 Gold is found in the earth almost always in a native state. There can be no doubt that it was much more abundant on the surface of the earth, and in the beds of rivers in the early periods of society, than it is at present: indeed this is obvious, from the account which Pliny gives of the numerous places in Asia and Greece, and other European countries, where gold was found in his time.
Gold, therefore, could hardly fail to attract the attention of the very first inhabitants of the globe; its beauty, its