1863.] 609 



peritoneum became speedily coated with coagulum. Here, it will be 

 observed, not merely the liquor sanguinis, but the corpuscles also 

 were present in the serous cavity, yet no coagulation took place in 

 contact with its walls. 



I think it probable, though not yet proved, that all living tissues 

 have these properties with reference to the blood. We know that 

 the interstices of the cellular tissue contain coagulable fluid, and I 

 have seen anasarcous liquid coagulate after emission ; but this indeed 

 may possibly have been merely liquor sanguinis, coagulating in con- 

 sequence of slight admixture of blood-corpuscles from the wounds 

 made in obtaining it. 



Looking now at the principal results which we have arrived at, it 

 must, in the first place, be admitted that the ammonia theory is to be 

 discarded as entirely fallacious. The fact that this theory is exceed- 

 ingly plausible, and has been supported by many ingenious argu- 

 ments and experiments, is of course no reason why we should retain 

 it if unsound. On the contrary, the more specious it is the more 

 necessary is it that it should be effectually cleared away ; for it 

 mystifies the subject of coagulation most seriously ; and I may say, 

 for my own part, that it has cost me an amount of experimental 

 labour of which the illustrations brought forward this evening con- 

 vey but little idea. Still these have been, I trust, sufficient to show 

 that the coagulation of the blood is in no degree connected with the 

 evolution of ammonia, any more than with the influence of oxygen 

 or of rest. The real cause of the coagulation of the blood, when 

 shed from the body, is the influence exerted upon it by ordinary 

 matter, the contact of which for a very brief period effects a change 

 in the blood, inducing a mutual reaction between its solid and fluid 

 constituents, in which the corpuscles impart to the liquor san- 

 guinis a disposition to coagulate. This reaction is probably simply 

 chemical in its nature ; yet its product, the fibrin, when mixed 

 with blood-corpuscles in the form of an undisturbed coagulum, 

 resembles healthy living tissues in being incapable of that cata- 

 lytic action upon the blood which is effected by all ordinary solids, 

 and also by the tissues themselves when deprived of their vital pro- 

 perties. 



These principles have, of course, very extensive applications to the 

 study of disease ; but I must content myself with alluding very 



