52 THE RESEARCHES OF HAMMARSTEN. [BOOK I. 



contain paraglobulin or at most mere traces of it. This surmise is 

 however thoroughly incorrect, as Hammarsten's quantitative analyses 

 have shewn that such fluids contain, on the contrary, very consider- 

 able quantities of paraglobulin. This paraglobulin possesses, how- 

 ever, no fibrinoplastic activity, affording another proof that the fibrino- 

 plastic property is to be ascribed to some contaminating substance. 

 4th. The most weighty fact in opposition to Schmidt's hypothesis is 

 however the possibility of obtaining solutions of nbrinogen which 

 are free from paraglobulin, and which, when treated with ferment 

 solutions which are free from paraglobulin, yield typical fibrin. 



The observations of Hammarsten corroborate those of Schmidt 

 in reference to the living plasma containing less paraglobulin than 

 serum, and he believes with Schmidt that some of the paraglobulin 

 is derived from the colourless corpuscles ; he does not however, 

 as has been said in speaking of paraglobulin, ascribe the origin of 

 this body entirely to this source ; much is doubtless present in solu- 

 tion in the living liquor sanguinis, and some may perhaps originate as 

 a product in the decomposition which gives rise to fibrin, for even 

 Hammarsten was at first inclined to view coagulation very much 

 as Denis did, viz. as being a process in which a complex body decom- 

 poses with the formation of simpler products, of which fibrin is one. 



Hammarsten corroborates Schmidt also in his statement that 

 the addition of paraglobulin to scantily coagulating plasma or to a 

 transudation which will not coagulate in the presence of ferment, 

 may in the first case lead to an increase of the fibrin produced and 

 in the second to the production of a coagulum. But Hammarsten 

 shews that many substances besides paraglobulin will under the same 

 circumstances exert the same fibrinoplastic influence. The addition 

 for example of calcium chloride, CaCl 8 , to some specimens of hydrocele 

 fluids, which will not coagulate on the addition of Schmidt's fibrin- 

 ferment, produces the same effect as the addition of paraglobulin. 



If paraglobulin were specifically one of the fibrin-factors, it would 

 not, presumedly, be replaceable by any other proteid substance. Ham- 

 marsten having, however, by a process for which the original must 

 be consulted, prepared casein which was readily soluble in solutions 

 of sodium chloride, found that the addition of its solution to transu- 

 dations led not merely to an acceleration of the process of coagula- 

 tion, but to a remarkable increase in the amount of fibrin formed. 



In other experiments he found that the mere neutralization of 

 a transudation, which does not coagulate spontaneously, will often 

 lead to coagulation setting in. Furthermore, Hammarsten has 

 found that from some hydrocele fluids, which will not coagulate on 

 the addition of fibrin-ferment, it is possible to separate, by his 

 process, fibrinogen, which when dissolved and treated with the same 

 fibrin-ferment, will yield a coagulum of fibrin. 



It is obvious, then, that in a fluid there may exist substances 

 which either hinder the formation of fibrin, or prevent its precipita- 

 tion when formed. We know, for instance, that such substances 



