Note 68 — Chapter II

Until the last twenty or five-and-twenty years, it used to be supposed that this combination took place in the lungs; but more careful experiments have made it probable that the oxygen unites with the carbon in the circulation, and that the blood-corpuscules are the carriers of the oxygen. Compare Liebig's Animal Chemistry, p. 78; Letters on Chemistry, pp. 335, 336; Turner's Chemistry, vol. ii. p. 1319; Müller's Physiology, vol. i. pp. 92, 159. That the combination does not take place in the air-cells is moreover proved by the fact that the lungs are not hotter than other parts of the body. See Müller, vol. i. p. 348; Thomson's Animal Chemistry, p. 633; and Brodie's Physiol. Researches, p. 33. Another argument in favour of the red corpuscules being the carriers of oxygen, is that they are most abundant in those classes of the vertebrata which maintain the highest temperature; while the blood of invertebrata contains very few of them; and it has been doubted if they even exist in the lower articulata and mollusca. See Carpenter's Human Physiol. pp. 109, 532; Grant's Comparative Anatomy, p. 472; Elliotson's Human Physiol. p. 159. In regard to the different dimensions of corpuscules, see Henle, Anatomie Générale, vol. i. pp. 457–467, 494, 495; Blainville, Physiologie Comparée, vol. i. pp. 298, 299, 301–304; Milne Edwards, Zoologie, part i. pp. 54–56; Fourth Report of British Association, pp. 117, 118; Simon's Animal Chemistry, vol. i. pp. 103, 104; and, above all, the important observations of Mr. Gulliver (Carpenter, pp. 105, 106). These additions to our knowledge, besides being connected with the laws of animal heat and of nutrition, will, when generalized, assist speculative minds in raising pathology to a science. In the mean time I may mention the relation between an examination of the corpuscules and the theory of inflammation which Hunter and Broussais were unable to settle: this is, that the proximate cause of inflammation is the obstruction of the vessels by the adhesion of the pale corpuscules. Respecting this striking generalization, which is still on its trial, compare Williams's Principles of Medicine, 1848, pp. 258–265, with Paget's Surgical Pathology, 1853, vol. i. pp. 313–317; Jones and Sieveking's Pathological Anatomy, 1854, pp. 28, 105, 106. The difficulties connected with the scientific study of inflammation are evaded in Vogel's Pathological Anatomy, p. 418; a work which appears to me to have been greatly overrated.