80 PATHOLOGY. 



In addition to those above named, Halliburton and Eauscben- 

 bach consider that plasma entirely free from white cells cannot 

 be made to coagulate in the usual way, but information on the 

 fibrin ferment is much less accurately determined than is the 

 case with almost any other known inorganic ensyme. 



FERMENT CONTAINED IN THE SECRETIONS OF ANIMALS 

 AND PLANTS. 



The following appears to be all that is really known : — (1.) 

 Temperature is of much account, action stops after 132f° F. 

 has been reached : 2. The amount of coagulative change is not 

 affected by the quantity of the ferment, only the rate, as with 

 all known ferments ; when the quantity is small the clotting 

 is slow : (3.) The ferment is precipitated along with gelatinous 

 matter found in its solutions ; 4. It is most probably not used 

 up, and a very small quantity indeed seems to be sufficient. 



It seems, however, to be the general opinion that the ferment 

 is perhaps derived from the disintegration of the white corpuscles 

 when blood is shed, or within the economy in certain conditions, 

 such as septic fevers, diseases of the blood-vessels, foreign bodies 

 introduced into them, pleuro-pneumonia contagiosa, the microbe 

 of which seeming to determine coagulation of the blood within 

 the vessels, and of the exudate in the surrounding structures of 

 the lungs, i.e., parenchyma cells, alveoli, and bronchi ; and it is 

 also found that an injection of ichor into the blood causes the 

 destruction of an enormous number of corpuscles, resulting in 

 spontaneous coagulation within the circulation, after which the 

 coagulability of the blood is diminished. From the foregoing 

 we can understand how in metritis and other septic diseases 

 where thrombi are abundantly formed, the blood itself may 

 coagulate more feebly than natural. 



Whilst fibrin is absent in healthy blood, it must be admitted 

 that the materials from which its factors are derived must be 

 contained in their proper conditions and proportions. But it is 

 equally evident that circulating blood contains no ferment so 

 long as both the fluid and the walls of the vessels are in a 

 normal condition. 



Coagulation of the blood varies in different animals, and is 



