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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    blow on the stomach, &c. In these cases we find the blood, after death, not only in as fluid a state as in the living vessels, but it does not even coagulate when taken out of them. As in the bodies of such persons no action of life takes place, the muscles do not con- tract. There are partial influences likewise which destroy the power of coagulation, as a blow on a part producing a considerable extravasation. This forms an ecchymosis, in which we shall often find the blood not in the least coagulated. In healthy menstruation the blood which is discharged does not coagulate; in the irregular or unhealthy it does. The healthy menses, therefore, show a pecu- liar action of the constitution; and it is most probably in this action that their salubrious purposes consist; for if twice the usual quan- tity is evacuated, with the power of coagulation, even from the same vessels, the same benefit is not produced, much less when taken away from another part by art.* Many substances, when mixed with the blood, prevent coagula- tion ; bile has this effect out of the body; but we cannot suppose that in a living body it can be taken into the blood in such quan- tity as to produce this effect; for we find in a very severe jaundice that the blood is still capable of coagulating strongly. That probably every inanimate fluid in nature, which is capable of being rendered solid, produces heat during that change, and in the contrary change cold, is commonly known. It is on this prin- ciple that Dr. Black has established his very ingenious theory of latent heat. Thus, in the freezing of water heat is produced. To see how far the coagulation of the blood was similar in this respect to the same change in other substances, I first coagulated the white of an egg, by applying to it rectified spirits of wine: the heat of both was the same before their union ; but I found, upon uniting them, that the white of the egg was immediately coagulated, and that the heat of the mixture was increased four, sometimes five degrees, according as it coagulated slowly or quickly.f As the blood in the animals upon which we most commonly make our experiments is warm, it becomes a difficult matter to ascertain whether it produces heat upon coagulation. In holding the ball of the thermometer in the stream of blood coming from the arm, I found the heat raised to 92°: I then took a cup of human blood, allowed it to coagulate, and put it up to the brim in water warmed to 92°, till the whole mass was heated to this point. I bled afterwards another person to the same quantity, in a similar cup, which was put into the same water. Having two well-regu- * [The healthy menstrual discharge, which is probably a true secretion, does not coagulate, because it contains no globules or fibrin. Brande found that it had the properties of a very concentrated solution of the colouring matter of the blood in a diluted serum. {Phil. Trans. 1812, p. 113.) Unhealthy menstrua- tion is attended with actual hemorrhage.] f [The disengagement of caloric in this case is to be ascribed to the union of the water contained in the albumen with the spirits of wine, and the consequent condensation which takes place. Albumen coagulated by dilute nitric acid does not evolve any heat.]