RIGIDITY AFTER DEATH. 659 



Physiology, no adequate explanation has been 

 offered. All parties agree, that it is a beautiful 

 provision of nature to arrest hemorrhage, by plug- 

 ging up divided vessels. When it was proved by 

 the analyses of Prevost, Dumas, Magendie, Denis, 

 and Le Canu, that the proportion of fibrin is al- 

 ways diminished by loss of blood, the rapidity of 

 its coagulation was referred by some to an excess 

 of serum, or of saline matter. But we have seen 

 that in cases of protracted disease, the serous 

 portion of the blood is augmented in relation to 

 the quantity of fibrin and red particles, while its 

 coagulation is both slower and weaker than in 

 health. 



The fact is, that although the blood of an ani- 

 mal exhausted by over exertion, like the last 

 running of blood in cases of excessive hemorrhage, 

 coagulates almost instantaneously, the crassa- 

 mentum is always loose and infirm. There is rea- 

 son to believe, that the rapidity of the process is 

 owing partly to diminished motion and vitality of 

 the blood ; and that, like the rigidity of the mus- 

 cles after death, it depends on the last remains 

 of contractility, as will appear from the follow- 

 ing facts. In the first place, it is well known, 

 that when blood is extravasated, and its motion 

 arrested, as in uterine hemorrhage, and in cases of 

 ecchymosis, it very soon coagulates, although 

 surrounded with living parts ; while it is equally 

 certain, that the action of the heart and general 



