HUNTER 387 imagined by Duhamel, but by means of additions to their extremities and circumference, excess of calcareous tissue being removed by the absorbents. Some of his most extraordinary experiments were to illustrate the relation of strength of constitution to sex. He exchanged the spurs of a young cock and a young pullet, and found that on the former the transplanted structure grew to a fair size, on the latter but little ; whereas a spur from one leg of a cock transferred to its comb, a part well supplied with blood, grew more than twice as fast as that left on the other leg. Another experiment of his, which required many trials for success, was the engrafting of a human incisor on the comb of a cock. 1 The uniting of parts of different animals when brought into contact he attributed to the production of adhesive instead of suppurative inflammation, owing to their possession of " the simple living principle." 2 The effects of habit upon structure were illustrated by Hunter s observation that in a sea-gull which he had brought to feed on barley the muscular parietes of the gizzard be came greatly thickened. A similar phenomenon was noticed by him in the case of other carnivorous birds fed on a vegetable diet. It was in 1772 that Hunter, in order effectually to gauge the extent of his own knowledge, and also to correctly express his views, which had been repeatedly misstated or ascribed to others, commenced his lectures on the theory and practice of surgery, at first delivered free to his pupils and a few friends, but subsequent to 1774 on the usual terms, four guineas. Though Pott, indeed, had perceived that the only true system of surgery is that which most closely accords with the curative efforts of nature, a rational pathology can hardly be said to have had at this time any existence ; and it was generally assumed that a knowledge of anatomy alone was a sufficient foundation for the study of surgery. Hunter, unlike his contemporaries, to most of whom his philosophic habit of thought was a mystery, and whose books contained little else than relations of cases, and modes of treatment, sought the reason for each pheno menon that came under his notice. The principles of surgery, he maintained, are not less necessary to be under stood than the principles of other sciences ; unless, indeed, the surgeon should wish to resemble " the Chinese philo sopher whose knowledge consisted only in facts." In that case the science must remain unimproved until fresh facts arise. Too much attention, he remarked, cannot be paid to facts ; yet a multitude of facts overcrowd the memory without advantage if they do not lead us to establish principles, by an acquaintance with which we learn the causes of diseases. Hunter s course, which latterly com prised eighty-six lectures, delivered on alternate evenings between the hours of seven and eight, lasted from October to April. Some teachers of his time were content to dismiss the subjects of anatomy and surgery in a course of only six weeks duration. The task of lecturing is said to have been to Hunter so formidable that at the commence ment of each course he was obliged to take half a drachm of laudanum. His class was usually small, and never exceeded thirty. Among its members at various times were Abernethy, Carlisle, Chevalier, Cline, Coleman, Astley Cooper, Home, Lynn, and Macartney. Hunter was deficient in the gifts of a good extempore speaker, being in this respect a remarkable contrast to his brother William ; and he read his lectures, seldom raising his eyes from the manuscript. His manner with his auditory is stated to 1 Essays and Observations, i. 55, 56. " May we not claim for him," says Sir Wm. Fergusson with reference to these experiments, " that he anticipated by a hundred years the scientific data on which the present system of human grafting is conducted ?" (Hunt. Orat., 1871, P- 17). 2 Essays and Observations, i. 115; cf. Works, i. 391. have been embarrassed and awkward, or, as Adams puts it (Obs. on Morbid Pois., p. 272), " frequently ungraceful," and his language always unadorned ; but that his " expres sions for the explaining of his new theories rendered his lectures often unintelligible " is scarcely evident in his pupils notes still extant. His own and others errors and fallacies were exposed with equal freedom in his teaching. Occasionally he would tell his pupils, "You had better not write down that observation, for very likely I shall think differently next year ; " and once to a question of Coleman s he replied, " Never ask me what I have said or what I have written ; but, if you will ask me what my present opinions are, I will tell you." He was always much gratified when, in the conversations that he encouraged his hearers to hold with him at the end of his lectures, he found that what he said was understood and appreciated. In January 1776 Hunter was appointed surgeon-extra ordinary to the king. He commenced in the same year his. Croonian lectures on muscular motion, continued annually, except in 1777, till 1782 : they were never published by him, being in his opinion too incomplete. In 1778 ap peared the second part of his Treatise on the Natural History of the Human Teeth, the first part of which was published in 1771. It was in the waste of the dental alveoli and of the fangs of shedding teeth that in 1754-55, as he tells us, he received his first hint of the use of the absorbents. Abernethy (Phys. Led., p. 196) relates that Hunter, being once asked how he could suppose it possible for absorbents to do such things as he attributed to them, replied, " Xay, I know not, unless they possess powers similar to those which a caterpillar exerts when feeding on a leaf." Hunter in 1780 read before the Royal Society a paper in which he laid claim to have been the first to make out the nature of the utero-placental circulation. His brother William, who had five years previously described the same in his Anatomy of the Gravid Uterus, thereupon wrote to the Society attributing to himself this honour. John Hunter in a rejoinder to his brother s letter, dated February 17, 1780, reiterated his former statement, viz., that his discovery, on the evening of the day in 1754 that he had made it in a specimen injected by a Dr Mackenzie, had been communicated by him to Dr Hunter. Thus arose an estrangement between the two Hunters, which con tinued until the time of William s last illness, when his brother obtained permission to visit him. In 1783 Hunter was elected a member of the Royal Society of Medicine and of the Royal Academy of Surgery at Paris, and took part in the formation of " A Society for the Improvement of Medical and Chirurgical Knowledge." 3 It appears from a letter by Hunter that in the latter part of 1783 he, with Jenner, had the subject of colour-blindness under consideration. As in that year the lease of his premises in Jermyn Street was to expire, he purchased the twenty-four years leasehold of two houses, the one on the east side of Leicester Square, the other in Castle Street, with intervening ground. Between the houses he built in 1783-85, at an expense of above 3000, a museum for his anatomical and other collections. These by 1782 had cost him 10,000, and contained preparations of numerous specimens presented by Sir Joseph Banks, the Honourable C. Greville, and Mr Walsh. The new edifice consisted of a hall 52 feet long by 28 feet wide, and lighted from the top, with a gallery all round, and having beneath it a lecture 3 The Transactions of the Society contain papers by Hunter on inflammation of veins (1784),- intussusception (1789), a case of para lysis of the muscles of deglutition (1790), and a case of poisoning during pregnancy (1794), with others written by Home, from materials supplied by him, on Hunter s operation fr the cure of popliteal aneur ism, on loose cartilages in joints, on certain horny excrescences of the
human body, and on the growth of bones.
