A treatise on the blood, inflammation, and gun-shot wounds / by John Hunter ; with notes by James F. Palmer.

  • John Hunter
Date:
1840
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the blood, inflammation, and gun-shot wounds / by John Hunter ; with notes by James F. Palmer. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    would appear from this to be more an object of attention in the machine than even the solids. This fluid part of an animal is called the blood, and in the animals with which we are most acquainted it is of a red colour. The nature and appearances of the blood have been more attended to in diseases, especially of the inflammatory kind, than in full health, as it is more expressive of disease when removed from the body than any of the solids, and undergoes changes which the solids do not. Some of these changes are produced by the separation of parts from one another; but as the body is seldom in perfect health, we can hardly procure the blood in the same state twice from one person, although it may not be sensibly diseased. In a history of the blood these varieties must be mentioned, although they are often slighter appearances of what we find in disease; for diseases cer- tainly throws great light on the natural history of the blood, and the apparent changes which it undergoes must have unavoidably called medical men to consider it with attention. The only knowledge, however, we have of any difference in the blood, arises from these varieties in its spontaneous changes when extravasated;* nor do these differences appear always to affect the real nature of the blood, as the animals often continue in health while they are going on. Blood is most probably as much alike in all animals as the mus- cle of one animal is like that of another, only with this difference, that some animals have not that part which gives it the red colour; but the other parts, as the lymph and serum, are, as far as I yet know, the same in all.f * [The progress of modern chemistry has not only enabled the pathologist to detect many diseased states of the blood which were perfectly unknown in the time of Hunter (see note, in Principles of Surgery, p. 136), but has enabled the physiologist also to pursue his investigations on entirely a new tack, from which the greatest acquisitions to science may he expected to accrue. In order, how- ever, that the alliance of chemistry with physiology may be really rendered useful, it is important to bear in mind that the object of the chemico-physiologist should be not so much to discover the modes in which the vital principle operates, as the results which those operations give rise to, so as to be able to trace their de- pendence on one another, or the relation in which they stand, as cause and effect. This can only be done by the most scrupulous and exact analyses of the animal fluids, and particularly of the blood, as the point de depart from whence all the others proceed. Hunter did not altogether reject these aids, although, from the state of organic chemistry at the time that this treatise was written, he was little disposed to place reliance on the re3ults which it afforded.] t [Berzelius has verified this observation, as far as regards the serum and fibrin in the higher orders of animals, but the globules are found to vary very considerably in size, shape, number, and composition in the different species. The same authority has also stated that there are two-thirds less of the muriates in ox blood than in that from the human subject, but a larger proportion of nitrogen. (Med. Chir. Trans., vol. iii.) This latter fact would, indeed, be very remarkable if true, considering that man lives for the most part on a highly azotized food, whereas the ox lives on food which contains no nitrogen at all. The recent researches, however, of Macaire and Marcet (Mem. de la Soc. de Phy. ct (PHut. Nat. de Geneve, v. 389), have not only shown the error of this particular fact, but, as far as concerns the ultimate analysis of the blood, have established 3