On the Coagulation of the Blood. 



265 



to place reliance on the experiments on dog's blood just quoted, as lie 

 finds it necessary to use an emulsion as thick as milk to produce the 

 effect, and it is well known that contact with any foreign matter, espe- 

 cially if it is finely divided, will hasten coagulation, and it cannot be 

 supposed that sufficient lecithin is normally concerned in forming fibrin 

 as to cause a thick emulsion like this. Moreover, addition of lecithin 

 does not cause the clotting of pericardial fluid, of hydrocele fluid, of 

 solutions of fibrinogen,* of dilute salted plasma,f and I am not aware 

 that it has been tried on pure plasma obtained by the living test-tube 

 experiment. It then simply hastens the coagulation of peptone 

 plasma, and peptone plasma, as I shall show more fully in the next 

 section, differs so much from normal plasma, that it is impossible 

 to draw correct conclusions from experiments performed with it, 

 unless they be supported by confirmatory evidence on solutions of 

 fibrinogen and pure plasma, such as one obtains from a vein, or from 

 the pericardial sac. 



The solutions of lecithin used were admittedly impure, J and it is 

 possible that there was present a certain amount of calcium sulphate, 

 even if there was no fibrin ferment. But supposing it was the 

 lecithin and not the impurities that hastened the coagulation in 

 question, it must be remembered that many other organic and 

 inorganic substances act similarly ; thus Nauck§ has shown that 

 small quantities of glycin, uric acid, &c, as well as lecithin hasten 

 coagulation, and Green|| that calcium sulphate does so also. But it is 

 not concluded from these observations that these are the chief agents 

 in bringing about the coagulation of the blood. I have found that 

 cell globulin contains no phosphorus, and Wooldridge admits^" that 

 Schmidt's ferment is free from lecithin. On the very same page, 

 however, he accounts for the loss of the activity of fibrin ferment, 

 which was observed to take place by Hammarsten when it was kept 

 long under alcohol, as being due to removal of lecithin.** 



The supposition that "fibrinogen A " acts by giving up its lecithin 

 to "fibrinogen B" to form fibrin, seems, therefore, to be a pure 

 assumption, and so far as I can find is unsupported by any analytical 

 evidence. Wooldridge has certainly shown that the fibrinogens (?) he 

 obtains from tissues contain phosphorus, but to this point I shall 

 return later. 



* ' Journ. of Physiol.,' vol. 4, p. 369. 

 f Private communication to the author. 

 t ' Journ. of Physiol.,' vol. 4, p. 369. 

 § ' Inaug. -Dissert.,' Dorpat, 18S6. 

 || Loc. ext. 



% ' Journ. of Physiol.,' p. 230. 



** This loss of activity is well explained by my theory, by supposing that the 

 longer cell globulin is kept under alcohol, the more insoluble in water does it become, 

 " : ke all other proteids. 



x 2 



