His merits in physics and chemistry. 10. Boyle improved the air-pump and the thermometer, though the latter was first made an accurate instrument of investigation by Newton. He also discovered the law of the air’s elasticity, namely, that its bulk is inversely as the pressure. For some of the principles of hydrostatics we are indebted to him, though he did not possess much mathematical knowledge. The Philosophical Transactions contain several valuable papers by him on this science.[1069] By his “Sceptical Chemist,” published in 1661, he did much to overturn the theories of Van Helmont’s school, that commonly called of the iatro-chemists, which was in its highest reputation; raising doubts as to the existence, not only of the four elements of the peripatetics, but of those which these chemists had substituted. Boyle holds the elements of bodies to be atoms of different shapes and sizes, the union of which gives origin to what are vulgarly called elements.[1070] It is unnecessary to remark that this is the prevailing theory of the present age.
[1069] Thomson’s Hist. of Royal Society, p. 400, 411.
[1070] Thomson’s Hist. of Chemistry, i. 205.
General character of Boyle. 11. I shall borrow the general character of Boyle and of his contemporaries in English chemistry from a modern author of credit. “Perhaps Mr. Boyle may be considered as the first person neither connected with pharmacy nor mining, who devoted a considerable degree of attention to chemical pursuits. Mr. Boyle, though in common with the literary men of his age he may be accused of credulity, was both very laborious and intelligent; and his chemical pursuits, which were various and extensive, and intended solely to develop the truth without any regard to previously conceived opinions, contributed essentially to set chemistry free from the trammels of absurdity and superstition, in which it had been hitherto enveloped, and to recommend it to philosophers as a science deserving to be studied on account of the important information which it was qualified to convey. His refutation of the alchemistical opinions respecting the constituents of bodies, his observations on cold, on the air, on phosphorus, and on ether, deserve particularly to be mentioned as doing him much honour. We have no regular account of any one substance or of any class of bodies in Mr. Boyle, similar to those which at present are considered as belonging exclusively to the science of chemistry. Neither did he attempt to systematize the phenomena, or to subject them to any hypothetical explanation.
Of Hooke and others. 12. But his contemporary, Dr. Hooke, who had a particular predilection for hypothesis, sketched in his Micrographia a very beautiful theoretical explanation of combustion, and promised to develop his doctrine more fully in a subsequent book; a promise which he never fulfilled; though in his Lampas, published about twenty years afterwards, he has given a very beautiful explanation of the way in which a candle burns. Mayow, in his Essays, published at Oxford about ten years after the Micrographia, embraced the hypothesis of Dr. Hooke without acknowledgment; but clogged it with so many absurd additions of his own as greatly to obscure its lustre and diminish its beauty. Mayow’s first and principal Essay contains some happy experiments on respiration and air, and some fortunate conjectures respecting the combustion of the metals; but the most valuable part of the whole is the chapter on affinities; in which he appears to have gone much farther than any other chemist of his day, and to have anticipated some of the best established doctrines of his successors. Sir Isaac Newton, to whom all the sciences lie under such great obligations, made two most important contributions to chemistry, which constitute, as it were, the foundation stones of its two great divisions. The first was pointing out a method of graduating thermometers, so as to be comparable with each other in whatever part of the world observations with them are made. The second was by pointing out the nature of chemical affinity, and showing that it consisted in an attraction by which the constituents of bodies were drawn towards each other and united; thus destroying the previous hypothesis of the hooks, and points, and rings, and wedges, by means of which the different constituents of bodies were conceived to be kept together.”[1071]
[1071] Thomson’s Hist. of Royal Society, p. 466.
Lemery. 13. Lemery, a druggist at Paris, by his Cours de Chymie in 1675, is said to have changed the face of the science; the change, nevertheless, seems to have gone no deeper. “Lemery,” says Fontenelle, “was the first who dispersed the real or pretended obscurities of chemistry, who brought it to clearer and more simple notions, who abolished the gross barbarisms of its language, who promised nothing but what he knew the art could perform; and to this he owed the success of his book. It shows not only a sound understanding, but some greatness of soul, to strip one’s own science of a false pomp.”[1072] But we do not find that Lemery had any novel views in chemistry, or that he claims with any irresistible pretension the title of a philosopher. In fact, his chemistry seems to have been little more than pharmacy.
[1072] Eloge de Lemery, in Œuvres de Fontenelle, v. 361. Biog. Universelle.
Sect. II.
ON NATURAL HISTORY.