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to influence his mind. He saw, on every side, marks of prosperity, and of long and uninterrupted success, not only in practical, but also in speculative, life; and he was told that these things were effected by a system which made facts the first consideration. He was ambitious of fame, but he perceived that the road to fame was not the same in England as in Scotland. In Scotland, a great logician would be deemed a great man; in England, little account would be made of the beauty of his logic, unless he was careful that the premisses from which he argued, were trustworthy, and verified by experience. A new machine, a new experiment, the discovery of a salt, or of a bone, would, in England, receive a wider homage, than the most profound speculation from which no obvious results were apprehended. That this way of contemplating affairs has produced great good, is certain. But it is also certain, that it is a one-sided way, and satisfies only part of the human mind. Many of the noblest intellects crave for something which it cannot supply. In England, however, during the greater part of the eighteenth century, it was even more supreme than it is now, and was, indeed, so universal, that, from the year 1727 until nearly the close of the century, our country did not possess, in any branch of science, a speculator who had sufficient force to raise himself above those narrow views which were then deemed the perfection of wisdom.239 Much was added to our knowledge, but its distant boundaries were not enlarged. Though there was an increase of curious and valuable details, and though several of the small and proximate laws of nature were generalized, it must be admitted, that those lofty generalizations, which we owe to the seventeenth century, remained stationary, and that no attempt was made to push beyond them. When John Hunter arrived in London, in 1748, Newton had been dead more than twenty years, and the English people, absorbed in practical pursuits, and now beginning, for the first time, to

239 See Buckle's History of Civilization, vol. i. pp. 808, 809.

enter into political life, had become more averse than ever to inquiries which aimed at truth without regard to utility, and had accustomed themselves to value science chiefly for the sake of the direct and tangible benefit which they might hope to derive from it.

That Hunter must have been influenced by these circumstances, will be obvious to whoever considers how impossible it is for any single mind to escape from the pressure of contemporary opinion. But, inasmuch as all his early associations had inclined him in another direction, we perceive that, during his long residence in England, he was acted on by two conflicting forces. The country of his birth made him deductive; the country of his adoption made him inductive. As a Scotchman, he preferred reasoning from general principles to particular facts; as an inhabitant of England, he became inured to the opposite plan of reasoning from particular facts to general principles. In every country, men naturally give the first place to what is most valued. The English respect facts more than principles, and therefore begin with the facts. The Scotch consider principles as most important, and therefore begin with the principles. And, I make no doubt that one of the reasons why Hunter, in investigating a subject, is often obscure, is that, on such occasions, his mind was divided between these two hostile methods, and that, leaning sometimes to one and sometimes to the other, he was unable to determine which he should choose. The conflict darkened his understanding. Adam Smith, on the other hand, in common with all the great Scotchmen who remained in Scotland, was remarkably clear. He, like Hume, Black, and Cullen, never wavered in his method. These eminent men were not acted on by English influence. Of all the most illustrious Scotchmen of the eighteenth century, Hunter alone underwent that influence, and he alone displayed a certain hesitation and perplexity of thought, which seems unnatural to so great a mind, and which, as it appears to me, is best explained by the peculiar circumstances in which he was placed.

One of the ablest of his commentators has justly observed, that his natural inclination was, to conjecture what the laws of nature were, and then reason from them, instead of reasoning to them by slow and gradual induction.240 This process of deduction was, as I have shown, the favourite method of all Scotchmen, and, therefore, was precisely the course which we should have expected him to adopt. But, inasmuch as he was surrounded by the followers of Bacon, this natural bias was warped, and a large part of his marvellous activity was employed in observations and experiments, such as no Scotch thinker, living in Scotland, would ever have engaged in. He himself declared, that thinking was his delight;22 and there can be no doubt that, had he been differently situated, thinking would have been his principal pursuit. As it was, the industry with which he collected facts, is one of the most conspicuous features in his career. His researches covered the whole range of the animal kingdom, and were conducted with such untiring zeal, that he dissected upwards of five hundred different species,

240" He followed his natural inclination. He preferred the more delusive, apparently the more direct, road, which has seduced so many philosophers. He sought to arrive at the general laws of nature at once by conjecture; rather than, by a close and detailed study of her inferior operations, to ascend, step by step, through a slow and gradual induction to those laws which govern her general procedure." Babington's Preface to Hunter's Treatise on the Venereal Disease, in Hunter's Works, vol. ii. p. 129. Compare the narrow and carping criticism in Foot's Life of Hunter, p. 163.

241 That I may not be suspected of exaggeration, I will quote what by far the greatest of all the historians of medicine has said upon this subject. "La majorité des médecins qui prétendaient s'être formés d'après Bacon, n'avaient hérité de lui qu'une répugnance invincible pour les hypothèses et les systèmes, une grande vénération pour l'expérience, et un désir extrême de multiplier le nombre des observations. Ce fut chez les Anglais que la méthode empirique en médecine trouva le plus de partisans, et c'est principalement aussi chez eux qu'elle s'est répandue jusqu'aux temps les plus rapprochés de nous. Sa propagation y fut favorisée, non-seulement par le profond respect que les Anglais continuent toujours de porter à l'immortel chancelier, mais encore par la haute importance que la nation entière attache au sens commun, common sense, et elle y demeura l'ennemie irréconciliable de tous les systèmes qui ne reposent pas sur l'observation." Sprengel, Histoire de la Médecine, vol. v. p. 411, Paris, 1815.

242 Clive says,

"Much as Mr. Hunter did, he thought still more. He has often told me, his delight was, to think." Abernethy's Hunterian Oration, London, 1819, p. 26.

exclusive of dissections of different individuals, and exclusive, too, of dissections of a large number of plants.243 The results were carefully arranged and stored up in that noble collection which he formed, and of the magnitude of which we may gain some idea from the statement, that, at his death, it contained upwards of ten thousand preparations illustrative of the phenomena of nature.244 By this means, he became so intimately acquainted with the animal kingdom, that he made a vast number of discoveries, which, considered singly, are curious, but which, when put together, constitute an invaluable body of new truths. Of these, the most important are, the true nature of the circulation in crustacea and insects;245 the organ of hearing in cephalopods;

the power possessed by mollusks of absorbing

243 Mr. Owen, in his interesting Preface to the fourth volume of Hunter's Works, says (p. vii.), "There is proof that Hunter anatomized at least five hundred different species of animals, exclusive of repeated dissections of different individuals of the same species, besides the dissections of plants to a considerable amount."

214 "Some idea may be formed of Hunter's extraordinary diligence, by the fact, that his museum contained at the time of his death, upwards of 10,000 preparations, illustrative of human and comparative anatomy, physiology, and pathology, and natural history." Weld's History of the Royal Society, London, 1848, vol. ii. p. 92.

245 "I have tested the conflicting evidence of these observers by dissection of the heart in the lobster; and you will perceive by this preparation that it is more complicated than even the Danish naturalist supposed, and fully bears out the opinion of Hunter in regard to the mixed nature of the circulation in the crustacea." Owen's Lectures on the Comparative Anatomy and Physiology of the Invertebrate Animals, 2d edit. London, 1855, p. 318. "Cuvier, misled by the anomalous diffused condition of the venous system, supposed that there was no circulation of the blood in insects; yet the dorsal vessel was too conspicuous a structure to be overlooked. Such, however, was the authority of the great anatomist, that the nature of the heart began to be doubted, and the strangest functions to be attributed to it. Hunter, however, who was prepared to appreciate the true state of the circulating system in insects, by his discovery of the approximately diffused and irregular structure of the veins in the crustacea, has described, in his work on the blood, all the leading characters of the circulation in insects as it is recognized by comparative physiologists of the present day." Ibid., p. 383. Compare Hunter's Essays and Observations on Natural History, London, 1861, vol. i. p. 108.

246 "The class called Sepia has the organ of hearing, though somewhat differently constructed from what it is in fishes." An Account of the Organ of Hearing in Fishes, in Hunter's Works, vol. iv. p. 294. At the bottom of the page Mr. Owen observes, in a note, "This is the first announcement of the existence of an organ of hearing in the Cephalopoda."

247

their shells; the fact that bees do not collect wax, but secrete it 248 the semicircular canals of the cetacea;249 the lymphatics of birds;250 and the air-cells in the bones of birds 251 We are also assured, that he anticipated the recent discoveries respecting the embryo of the kangaroo;252 and his published works prove, that, in the human subject, he discovered the muscularity of the arteries, 253 the muscularity of the iris,254 and the diges

247 Hunter discovered that the molluscous inhabitant of a shell had the power of absorbing part of its dwelling." Owen's Lectures on the Comparative Anatomy and Physiology of the Invertebrate Animals, London, 1855, p. 544. "Every shell-fish has the power of removing a part of its shell, so as to adapt the new and the old together, which is not done by any mechanical power, but by absorption." Anatomical Remarks on a New Marine Animal, in Hunter's Works, vol. iv. p. 469, edit. Palmer. In a note to this passage, it is said, that "the doctrine of the absorption of shell has been lately" (i. e. in 1833) "adduced as a new discovery."

248 "His keen observation did not fail to detect several errors which preceding naturalists had fallen into, especially with regard to the formation of the wax, which he proved to be secreted, not collected, by the animal." Ottley's Life of Hunter, p. 122. "The wax is formed by the bees themselves; it may be called an external secretion of oil, and I have found that it is formed between each scale of the under side of the belly." Observations on Bees, in Hunter's Works, vol. iv. p. 433.

249 "In the terminating part there are a number of perforations into the cochlea, and one into the semicircular canals, which afford a passage to the different divisions of the auditory nerve." Observations on the Structure and Economy of Whales, in Hunter's Works, vol. iv. pp. 383, 384. “The semicircular canals of the cetacea, described by Hunter in the paper on Whales, a structure which Cuvier rightly states that Camper overlooked, but incorrectly claims the discovery as his own." Preface to vol. iv. of Hunter's Works, p. xxi.

250 Dr. Adams, in his somewhat hasty Life of Hunter, says (pp. 27, 28), "Mr. Hewson always claimed the discovery of lymphatics in birds." But the truth is, that Hewson never claimed it. He says, "It may be necessary to mention here, that the dispute between Dr. Monro and me is, who first discovered the lacteals of birds? for as to the lymphatics in their necks (mentioned in this gentleman's note), these we both allow were discovered by Mr. John Hunter, about ten years ago." And, again, "These lymphatics in the necks of fowls were first discovered by Mr. John Hunter." Hewson's Works, edit. Gulliver (Sydenham Soc.), pp. 102, 145.

251 Hunter's Works, vol. iv. pp. xxi. 176.

252 "See Nos. 3731, 3734, 3735, in the Physiological series of the Hunterian Museum, in which there are evidences that Mr. Hunter had anticipated most of the anatomical discoveries which have subsequently been made upon the embryo of the Kangaroo." Rymer Jones' Organization of the Animal Kingdom, London, 1855, pp. 829, 830.

253 "The muscularity of arteries, of which John Hunter made physiological proof, is now a matter of eyesight." Simon's Pathology, London, 1850, p. 69. "To prove the muscularity of an artery, it is only necessary [254 For this Note, see next page.]

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