THEORIES OF COAGULATION. 177 



these substances readily yield, under the influence of certain reagents 

 and conditions, a body or bodies giving albumose reactions ; and he finds 

 that such a body is also present in the blood after their injection, and 

 rapidly appears in the urine. 1 Wright considers it probable, therefore, 

 that the contrary effects of large and rapid, or small and gradual, 

 administration of these extracts is due in the one case to the immediate 

 action of the nucleo-proteids in effecting the conversion of the fibrinogen 

 into fibrin before there has been time for the formation of albumose ; 

 and in the other case, where there has been time for such formation, to 

 the action of the albumose thus formed in preventing coagulation (as 

 in the case of directly injecting albumose into the blood vessels). If 

 any albumose is formed, the action of this would, by delaying coagula- 

 tion, give time for the formation of more, when a second dose of 

 nucleo-proteids is injected. Hence, a dose of nucleo-proteid, which would, 

 if administered rapidly, produce instantaneous coagulation throughout 

 the vascular system, may, if administered gradually, tend altogether to 

 prevent coagulation. But, as Halliburton points out, the explanation of 

 the action of "peptone" in producing a negative form of coagulation 

 may be that it liberates small quantities of nucleo-proteid, rather than 

 that it removes calcium ; and if this is so, the explanation offered by 

 Wright (and Pekelharing) of the action of nucleo-proteids falls to the 

 ground. Moreover, it cannot be accepted as proven that a " peptone " 

 moiety is split oft' from nucleo-proteid. " Peptone " (i.e. " albumose")- 

 blood is characterised by extreme diminution of the amount of C0 2 

 which it contains, 2 and by diminished alkalinity, 3 and the reason for 

 the uncoagulability of such blood is apparently connected with its 

 deficiency in C0 2 tension, 4 since it coagulates on passing a stream of 

 C0 2 throughout it. For the occurrence of intra vascular coagulation, 

 after injection of nucleo-proteid and similarly acting substances, is 

 largely influenced by the amount of C0 2 in the blood, and it is due to 

 its richness in C0 2 that the blood coagulates under these circumstances, 

 first in the systematic veins, and of these most readily in the portal 

 venous system. 5 



From what has been before said as to the influence of lime, it will be 

 understood that the lime-salts of the plasma play an essential part in the 

 interaction between the nucleo-proteid and the fibrinogen. This parti- 

 cipation of lime in the reaction had not yet been recognised when 

 Wooldriclge's researches were made, but is freely admitted by Wright, 

 whose views upon the subject of the combined action of nucleo-proteid 

 and lime in producing coagulation seem to be in close agreement with 

 those of Pekelharing (see p. 171). It is, however, still by no means 

 clear why in " peptone " plasma, where all the necessary factors for the 

 formation of fibrin are present, coagulation, nevertheless, does not occur, 



1 This lias been also shown independently by Pekelharing ("Untersuch. u. d. Fibrin- 

 ferment," Amsterdam, 1892), who offers a similar explanation of the phenomenon of 

 negative and positive coagulation. Halliburton and Pickering, on the other hand, con- 

 sider that, in the case of colloids, the negative phase cannot be regarded as a subsidiary 

 phenomenon, due to disintegration of the material intravenously injected, but is rather a 

 result characteristic of the action of small doses, and is comparable to the inhibitory action 

 of small doses of certain drugs, which act contrary to the action of larger doses (such as the 

 physiological immunity produced by small doses of alexines). 



2 Lahousse, Arch. f. PhysioL, Leipzig, 1889, S. 77. 



3 Salvioli, Arch. ital. de Uol., Turin, 1892, vol. xvii. p. 155. 



4 Wright, loc. cit., andJourn. Path. andBaderiol., Edin. and London, 1893, vol. i. p. 434. 



5 Wright, Journ. PhysioL, Cambridge and London, 1891, vol. xii. 



VOL. I. 12 



