The Story of Alchemy and the Beginnings of Chemistry

How different is this conception of a change wherein substances are formed, entirely unlike those things which react to form them, from the alchemical presentment of such a process! The alchemist spoke of stripping off the outer properties of the thing to be changed, and, by operating spiritually on the soul which was thus laid bare, inducing the essential virtue of the substance to exhibit its powers of transmutation. But he was unable to give definite meanings to the expressions which he used, he was unable to think clearly about the transformations which he tried to accomplish. The chemist discards the machinery of virtues, souls, and powers. It is true that he substitutes a machinery of minute particles; but this machinery is merely a means of thinking clearly and consistently about the changes which he studies. The alchemist thought, vaguely, of substance as something underlying, and independent of, properties; the chemist uses the expression, this or that substance, as a convenient way of presenting and reasoning about certain groups of properties. It seems to me that if we think of matter as something more than properties recognised by the senses, we are going back on the road which leads to the confusion of the alchemical times. The alchemists expressed their conceptions in what seems to us a crude, inconsistent, and very undescriptive language. Chemists use a language which is certainly symbolical, but also intelligible, and on the whole fairly descriptive of the facts. A name is given to each elementary substance, that is, each substance which has not been decomposed; the name generally expresses some characteristic property of the substance, or tells something about its origin or the place of its discovery. The names of compounds are formed by putting together the names of the elements which combine to produce them; and the relative quantities of these elements are indicated either by the use of Latin or Greek prefixes, or by variations in the terminal syllables of the names of the elements.