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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    In a priapism the blood does not coagulate, except it threatens mortification. The separation of the blood, either from itself, that is when divided into small portions, or separated from the living body, becomes one of the immediate causes of the coagulation of the lymph ; therefore the contact of blood with blood, or with living vessels, in some degree retards coagulation : this is the reason why blood which comes from the vessels slowly, or falls from some height, or runs some way on the surface of a dish, coagulates sooner than when the contrary circumstances happen ; and upon this principle it is, that blood when shaken in a phial will coagu- late the sooner, even if shaken in a vacuum. A deep mass of blood is also, from the same cause, longer in coagulating than a shallow one. From the above observations it must appear evident that neither cold, nor air, nor rest alone, has any influence on the coagulating power of the blood; there must, therefore, be some other principle on which this process depends; and, as it retains its fluid state while circulating, and even for a long time when at rest in the living vessels, and coagulates when the vessels or the body dies, it might naturally be supposed that it was the life of the body or vessels which kept it fluid ; we know, however, that life in the body or vessels does not hinder the blood from coagulating; under certain circumstances, but often rather excites coagulation. Nor does death, in the body or vessels, in all cases become a cause of coagu- lation ; for we find that in many who die suddenly from a strong impression of the mind, the blood does not coagulate; there is, therefore, something more than the mere situation of the blood, surrounded with dead parts, that allows of coagulation ; and that must be a something in the blood itself. From these observations it must be evident that the fluid state of the blood is connected with the living vessels, which is its natural situation, and with motion ; and that where there is a full power of life, the vessels are capable of keeping the blood in a fluid state. 1 believe, however, very little motion is required to keep up this fluidity when the other is present. A total stagnation of the blood while the body is alive, as in a trance, or where the circulation has been stopped for several hours, as in the case of persons apparently drowned,* does not make it coagulate; yet where there are no actions going on in a part, if the blood stagnates for a much shorter time than in a trance, it will be found coagulated, as in mortifica- * [It is difficult to reconcile the results of physiological experiment with the accounts which have been given of recoveries from protracted asphyxia. It is extremely doubtful, under the most favourable circumstances, whether in drown- ing the heart ever continues to pulsate for so long a period as five minutes after the cessation of respiration, or whether, having stopped its actions, it can ever be renewed. In trances also and the ordinary forms of syncope it is questionable whether the functions of respiration and circulation are ever wholly arrested. The statements which have been made on these subjects are certainly without founda- tion, and no better than extravagant fables.]