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CHAPTER VI.

OPINIONS DURING THE TRANSITION FROM ALCHEMY

ΤΟ CHEMISTRY.

THE ages so rapidly passed over comprehend two thousand years. The attainment in chemical science has been as yet small. All the theories have been abstract; they have been efforts of the mind to comprehend matter, with a very meagre, if any, classification of phenomena. We might ask ourselves if this was caused by the scarceness of facts, or by the want of a mind to perceive them. As to scarceness of information this may be doubted, numerous truly chemical arts had been from early ages in use; many had fallen into disuse. The observers that now come to the science are not so much characterized by the multitude of their discoveries, as by the minuteness of their observations, and the penetrating nature of their reasonings. The progress of mankind has often been compared with the progress of individuals, and the analogy serves here to point out a cause. In the history of every mind, especially of the mind of the student, there are seasons where facts are collected and books read with diligence, theories formed in great numbers, reasonings adopted and thrown aside; opinions are heaped up, but no distinct opinion is formed, and a vague stare into the difficulties before it is the only result of the labour, for knowledge it can scarcely be called, where nothing is well arranged, and nothing is actually known. The imagination then takes the place of the helpless reason. A poetical mind may find in this state a field for its highest powers, a weaker mind will seek explanations more or less mystical, and a still weaker mind will be contented with the merely mysterious. But a vigorous mind, in which reasoning and observation predominate, is found gradually to

collect from the disorderly information, certain impressions, which, in time, become more distinct, until at last an idea is obtained which can be laid hold of. Whether this idea be false or true, is of little consequence; it is in any case enough to give order to the museum of his mind, and for the first time that mind may be said to be informed. Every thing is examined under the influence of this idea, which may change constantly, as it is constantly seen to be unsuited to the facts, but every change may be a progress; and even if from false to false, is nevertheless a constant gain, so much false being left behind. The dreaming age of chemistry had lasted long; the minds occupied had been satisfied either with the more poetical observation of nature, or with the mystic and mysterious; an idea had entered into the mind of the chemists of the age, that some exact explanation could be obtained, and so we find them hunting it down from point to point with acuteness, energy, and hope, ever increasing as the object seemed rapidly to be approached. But how was this idea first attained? How does the first idea rise in the mind of the individual enabling him to see order and beauty in all the shapeless learning that he had been amassing? It is a progress of mind which is not for us to discuss here. The requisite for it is intellectual energy, and how that has been aroused in modern Europe, many great writers have done their best to show. It was by a combination of many great causes, natural stages in the education of the species. We are surprised to find that the finest writers of the world should have existed when thinkers in science were scarcely at the rudiments; but we see constantly that the highest literary powers may be unfit to comprehend any scientific truth firmly, and we see, even among the scientific world, that some branches have still scarcely begun their independent life. The world cultivated poetry and eloquence, and attained the highest stage that we know, when no law in the mixed sciences could be rigidly and certainly stated. The writers, quoted in this chapter,

go over again much of the same theoretical ground traversed before, but frequently with much less philosophical grasp than the ancients, and much less largeness of conception, although they frequently gain by what seems the littleness of their ideas, and the smallness of their aims. They are contented to speculate on an acid, instead of the formation of a world, whilst those who take a wider ground, such as Newton and Boscovich, can only be said, as far as our subject is concerned, to reproduce and improve earlier philosophies.

The tendency from this time is to increase the number of bodies, which, if not at first called elements, are at least treated as such. This is a needful step towards the chemical theory of matter in its present stage.

Glauber, although a believer in the general transmutability of substances, did much to help forward the notion of distinct elements in his observations on the affinity of bodies. He explains the evolution of ammoniacal gas from sal ammoniac by a fixed alkali, showing that he understood well combination and decomposition, the stumbling-block of so many, and the introduction to definite compounds. "But that a spirit is distilled off by the addition of fixed salts; the reason is that fixed salts are contrary to acid salts, and if they get the upper hand do kill the same, and rob them of their strength, whereby those things which are mixed with them are freed from their bond, and so it falls out here with salt armoniack, that when by addition of a vegetable fixed salt, the acidity of the salt armoniack is killed; the salt of urine, which formerly was bound therewith, gets its former freedom and strength, and being sublimed turns into a spirit.” *

Boyle, who attacked alchemy, and may almost be said to have begun modern chemistry, or rather let us say the transition period, seems to have had one of the clearest, most straightforward, and most common-sense methods of viewing

*

Page 49. The Works of the Highly Experienced and Famous Chymist, John Rudolph Glauber. London, 1639.

phenomena, of any of his period. One feels, on reading his works, that on another subject he might have written so as to be even now and at all times read with delight, whereas, in the dangerous and difficult fields of chemistry, he has only left matter serving as landmarks, to shew us the way in which the mind has been obliged to wander in search of truth.

Boyle says, when treating of the "origin of form and qualities,' "There is one universal matter common to all bodies, an extended, divisible, and impenetrable substance."

And in the "Sceptical Chemist." "But the Aristotelian hypothesis (i.e., of the four elements) is not comparable to the mechanic doctrine of the bulk and figure of the smallest parts of matter, for from these more universal and fruitful principles of the elementary matter, may spring a great variety of textures, upon whose account a multitude of compound bodies might greatly differ from one another." In p. 282:-" Now if it be true, as 'tis probable, that compound bodies differ from one another, in nothing but the various textures, resulting from the magnitude, shape, motion, and arrangement of their small parts, it will not be irrational to conceive that one and the same particle of universal matter, may by various alterations and contextures be brought to deserve the name sometimes of a sulphureous, and sometimes of a terrestrial or aqueous body."

He attacks severely the four elements, the three elements, and the five elements, and justly complains of the "intolerable ambiguity" of the writers on chemistry, and "their playing upon words," as their mode of using salt, sulphur, and mercury decidedly is.

To continue from Boyle. "It seems probable that at the first production of mixt bodies, the universal matter whereof they consist was actually divided into little particles of several

* Vol. I., p. 197. The philosophical works of the Hon. Robert Boyle, Esq. Abridged, methodized, &c., by Peter Shaw, M.D. 2nd edition, 1738. † Vol. III., p. 266.

'Tis also

sizes and shapes variously moved. possible, that of these minute particles many of the smallest and contiguous ones were associated into minute masses, and by their coalitions constituted such numerous little primary concretions, as were not easily separable into the particles that compose them." *

"And indeed if we consider how far the bare change of texture, whether made by art or nature, can go, in producing such new qualities, in the same parcel of matter; and how many inanimate bodies we know to be denominated and distinguished, not so much by any imaginary substantial form, as by the aggregate of these qualities; and that the variation of figure, size, motion, situation, or connection of the corpuscles, whereof any of these bodies is composed may alter the fabric of it; we shall have cause to suspect, that there is no need that nature should always have elements provided, whereof to compose mixed bodies; and that it is not so easy as chymists and others have hitherto imagined, to discern which among the many different substances, without any extraordinary skill, to be obtained from the same portion of matter, ought, exclusive of the rest, to be esteemed its elementary ingredients; much less to determine what primogeneal and simple bodies conspired together to compose it."

*

"Our experiment affords us a considerable argument in favour of that part of the mechanical hypothesis which teaches inanimate bodies to differ from one another, but in the magnitude, shape, motion, texture, and, in a word, the mechanical properties of the minute parts they consist of." Page 360. At the end of the chemical doctrine of qualities, p. 441,-" In short, these hypotheses greatly hinder the progress of human knowledge, that introduce morals and politics into philosophy, where all things are transacted according to mechanical laws."

* Vol. III., p. 263. + Page 350.

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