62 THE BLOOD. 



and solids, as the crystalline lens, chyle and lymph, connec- 

 tive tissue, &c., which are found capable of exciting coagula- 

 tion in serous fluids, is probably identical with the globulin of 

 the red corpuscles. 



The fibrinogenous matter obtained from serous effusions dif- 

 fers but little, chemically, from the fibrinoplastin. 



Thus in the experiment before mentioned, the globulin or 

 fibrinoplastic matter of the blood-cells in the clot causes co- 

 agulation by uniting with the fibrinogen present in the hydro- 

 cele-fluid. And whenever there occurs coagulation with the 

 production of fibrin, whether in ordinary bloodclotting, or in 

 the admixture of serous effusions, or in any other way, a like 

 union of these two substances may be supposed to occur. 



The main result, therefore, of these very interesting experi- 

 ments and observations has been to make it probable that the 

 idea of fibrin existing in a liquid state in the blood is founded 

 on a mistaken notion of its real nature, and that, probably, it 

 does not exist at all in solution as fibrin, but is formed at the 

 moment of coagulation by the union of two substances which, 

 in fluid blood, exist separately. 



The theories before referred to, concerning the coagulation 

 of the blood, will therefore, if this be true, resolve themselves 

 into theories concerning the causes of the union of fibrino- 

 plastin and fibrinogen ; and whether, on the one hand, it is an 

 inhibitory action of the living bloodvessels that naturally re- 

 drains, or a catalytic action of foreign matter that excites, the 

 union of these two substances. 



Conditions affecting Coagulation. 



Although the coagulation of fibrin appears to be sponta- 

 neous, yet it is liable to be modified by the conditions in 

 which it is placed; such as temperature, motion, the access 

 of air, the substances with which it is in contact, the mode, of 

 death, &c. All these conditions need to be considered in the 

 study of the coagulation of the blood. 



The coagulation of the blood is hastened by the following 

 means : 



1. Moderate warmth, from about 100 F. to 120 F. 



2. Rest is favorable to the coagulation of blood. Blood, of 

 which the whole mass is kept in uniform motion, as when a 

 closed vessel completely filled with it is constantly moved, co- 

 agulates very slowly and imperfectly. But rest is not essen- 

 tial to coagulation ; for the coagulated fibrin may be quickly 



