1881.] Blood Corpuscles to the Coagulation of the Blood. 415 



2. Behaviour of Leucocytes towards Plasma. 



The only animals at the author's disposal were dogs. The most 

 convenient way of obtaining plasma from dog's blood is to inject a 

 solution of peptone into the blood of the living animal. If the animal 

 be bled five or ten minutes after the injection of the peptone, the 

 blood does not coagulate. (This fact was discovered by Dr. Adolf 

 Schmidt, Mulheim.) 



By means of the centrifugal machine the blood corpuscles can be 

 separated from the plasma. With this plasma I have experimented, 

 and I shall call it peptone plasma. 



A general account of the action of peptone on the blood has been 

 published by my friend, Dr. Fano. His researches were also carried 

 out at Leipzig, and his observations have supplied me with many 

 necessary details. My observations have led me to the conclusion that 

 peptone plasma behaves towards the cells in a manner which is essen- 

 tially similar to that in which solutions of common salt, of sulphate of 

 magnesia, and distilled water behave. As I have already stated, by 

 these latter reagents the protoplasm of the lymph cells becomes con- 

 verted into a fibrous mass resembling fibrin. 



When peptone plasma is the destroying agent r the substance pro- 

 duced is undoubtedly fibrin, and it owes its origin to a simple trans- 

 formation of the protoplasm, of the leucocytes into fibrin. It is per- 

 fectly independent of the presence of a fibrinogenic substance in the 

 plasma. 



The grounds on which I base this statement are clearly brought 

 forward in the following experiments, which I shall adduce as 

 examples. 



A dog was injected with peptone ; five minutes afterwards it was 

 bled. The corpuscles were separated from the plasma by the centri- 

 fugal machine, and the plasma allowed to stand overnight in ice. 

 During the night, incomplete coagulation of the plasma occurred. 



This is a perfectly normal occurrence in peptone plasma, and it can 

 be immediately brought about by dilution of the plasma with water, 

 or by passing a stream of carbonic acid through it. 



The plasma in question, after the coagula had been separated by 

 filtration > presented the following characters : — 



It was totally uncoagulable — 



1. On dilution with water. 



2. On passing a current of C0 2 through it. 



3. On addition of Schmidt's fibrin ferment. 



4. On addition of paraglobulin. 



5. On addition of normal serum. 



6. On standing till it was foul. 



