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

  • Hunter, John, 1728-1793.
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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    The circumstances attending the coagulation of the lymph are subject to great varieties. These depend upon or correspond with the state of the body at the time, of which we can best judge by the readiness or difficulty with which the blood coagulates, and by the firmness or looseness of the coagulum. The whole mass of the blood being a compound, of which the parts are in some degree separated, the appearances upon coagulation are attended with still more variety than the lymph alone could exhibit, or than could occur in those animals which are not possessed of red blood, as the red part brings to view many of the changes in the lymph, by the difference of its colour, as well as of its specific gravity. The three substances, which become visibly distinct when the lymph coagulates, differ as to gravity: the serum is the lightest, and, remaining fluid, swims upon the top ; the red globules, which undergo no change, are the heaviest, and sink more or less in the lymph; but being entangled in it, add to its weight, so as to make it sink deeper in the serum.* pound is fluid of which fibrin forms one ingredient, but the serum is essential to its fluidity. The compound nature of the liquor sanguinis is, I think, further shown from the fact that spirits of wine or turpentine does not immediately affect fresh-drawn blood, although they instantly coagulate the albumen of serum which has once separated from the clot. In answer 10 the particular objection urged by our author to this view of the subject, it may be replied : 1st, that there is as much reason for helieving that the fluids of dropsy, &c, are secreted, as there is that they are simply exuded; for, 2d, these fluids differ in composition from the ordinary serum of the blood; and 3d, effusions of serum never take place without corresponding effusions of lymph, and vice versa. This latter point has been particularly discussed by Dr. Babington in the paper before cited.] * [The specific gravity of the blood has been variously stated by different ex- perimentalists. According to Davy and Scudamore, it is from 1049 to 1051 ; Ure makes it 1053; Prout, 1030 to 1055; Blumenbach, 1050 ; Haller, 1053; Fourcroy, 1056; .Turin, 1054; Henry, 1053 to 1126; Whiting, 1055; Denis, 1059; Thackrah, 1041. These differences have no doubt partly arisen from variations in the state of the system at the time the blood was taken. Brande found that the specific gravity of healthy blood occasionally rose to 1071. Blood, whether buffed or not, has generally a greater specific gravity in acute diseases than under ordinary circumstances ; but the reverse obtains in diseases of debility. 1050 is the standard which will be assumed in the following notes. The specific gravity of serum is subject to scarcely less variation than that of the blood ; but I shall content myself on the present occasion with merely stating that the medium 1029-5, as mentioned by Dr. Marcet, is now generally admitted! Dr. Davy represents the specific gravity of the red globules as 1087, of the colouring matter as 1126 to 1130, of the coagulable lymph as 1046 to 1060, and of the whole clot as 1077 to 1084. 1 conceive, however, in regard to this latter point, that some error must have existed in the experiments'; for, as the clot floats in the serum, there cannot, it should seem, be much real difference between them : not to insist on the fact, which will afterwards be adverted to, and which Dr. Babington was the first to point out, viz., that the coagulum which results from the buffy fluid which is skimmed off from inflammatory blood is uniform in density throughout, which could not possibly happen if the fibrin were lighter or heavier than the serum. (See Babington, Med.-Ch. Trans., xvi. 298, et. sen.) This indeed is one of the arguments which the gentleman above-mentioned has ingeniously employed to prove the homogeneity of the liquor sanguinis, as stated in the preceding note, and it must be admitted to have considerable force ]