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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    Many causes have been assigned for the coagulation of the lymph, which appear to me to be ill founded. It frequently hap- pens that when changes take place in matter of which the imme- diate causes are unknown, the mind refers them to some circum- stances which accompany these changes, although, perhaps, they may have had no concern whatever in producing them, and may be only attendants. This will always be the case where those changes arise out of the nature of the part itself. A seed put into moist ground grows: but the moist ground is only a necessary at- tendant, and not the immediate cause. The life of the seed, stimu- lated to action by the moisture, is the immediate cause of its growth, and it continues to grow because its action is always excited. All the water in the world would not make a dead seed grow. The same mode of distinction is applicable to the coagulation of the lymph. The first observations on the blood were most probably made on that of the more perfect animals, whose heat is commonly greater gressively diminished. Hence it seems that the contractility of the clot con- tinues for three days, during which time serum is expelled ; but after that period relaxation occurs, and a part of the expressed serum is reabsorbed. As the degree in which the clot contracts is inversely as the rapidity of the coagulation, whatever influences the coagulation of the blood so as to accelerate or retard this process will have a corresponding influence on the contraction of the clot and the relative quantity of serum which is afterwards expressed. About 10 parts serum to 13—14 crassamentum may be assumed as the standard of health ; but, like the contraction of muscles after death, it varies infinitely in different cases. Dr. Babington found the proportion of serum and crassamentum to vary materially in the same blood drawn into differently-shaped vessels. Thus, blood drawn into a pear-shaped vessel and a common basin exhibited the following dif- ferences : Temperature of blood.iof serum Specific gravity | of blood.iof serum Crass, in pear-shaped bottle. Crass. in basin To serum Vertigo during pregnancy . 87° 60 87 90 65° 60 60 60 1050 1049 1044 1048 1027 1028 1028 1024.6 1495 945 960 1292 2230 1716 1090 1717 1000 1000 1000 1000 The nearer the form of the vessel approaches that of a cube or sphere, the greater will be the proportion of serum. This difference is owing to the greater or less distance of the coagulating particles of fibrin from a common centre, which causes a more or less powerful adhesion or contraction of these particles. Per- haps few facts relating to the phenomena of venesection are of more practical importance than this, since blood is said to be thick or thin, rich or poor, in reference to the quantity of crassamentum it contains, and views of a disease are founded upon these supposed conditions, which, after all, depend not on the blood itself, but on the vessel into which it is received (op. cit., p. 297). Thackrah found a similar diversity to arise from the composition of the recipient vessel, a circumstance which he attributed to the electric states of the different metals composing it. Thus, while one quantity of the same blood coagulate! in a copper vessel in two minutes, and afforded 345.7 serum to 654.3 crass., another equal quantity coagulated in a pewter vessel in 1 min. and 10 sec, and afforded only 51.1 serum to 945.9 crass, (op. cit. p. 66).]