1911.] 



On the Fate of Red Blood Corpuscles, etc. 



257 



The tubes are kept in the incubator at 37° C, being thoroughly shaken 

 from time to time, and at the expiration of two hours the red blood corpuscles 

 are counted by the Thoma-Zeiss apparatus. 



Eight animals were injected in this way with quantities varying from 

 about 2 to 4 litres, and in all these animals a similar course of events was 

 observed, the number of the foreign corpuscles in the circulation gradually 

 diminishing until they disappeared ; the disappearance took place after a lapse 

 of from four to seven days after the injection and appeared to be related to 

 the amount of blood injected. Shortly after the disappearance of the foreign 

 corpuscles from the circulation, the blood serum began to acquire hemolytic 

 properties. 



The annexed curve showing the results of the blood counts in one 

 particular animal (Bull No. 72) may be taken as typical of the general 

 results. This animal, a Cyprus bull weighing 412 kilos., was bled 

 2-f litres from the jugular vein. It then received an intravenous injection 

 of 2540 c.c. of the freshly drawn and citrated blood of another bull 

 (No. 73) ; this volume of citrated blood corresponds to 2117 c.c. of pure 

 blood. About a quarter of an hour later a sample of blood was taken 

 from the jugular vein and run into citrate, and similar samples were taken 

 every day. 



On examination by the method previously indicated the following results 

 were obtained : — 



Bull No. 72. 



Date. 



No. of red blood corpuscles per 

 square of Thoma-Zeiss apparatus. 



Foreign. j Own. 



Percentage 



of 



foreign corpuscles. 



1911. 









April 30 



1-4 



11-7 



10 -7 





0-77 



10 -7 



6-7 





0-58 



10 -3 



5-3 



: I 



0-44 



10-6 



4-0 



4 













The above results are shown as ordinates on the annexed curve. 



It will be seen from this curve that immediately after the transfusion 

 the foreign corpuscles represented 10*7 per cent, of the total number of 

 corpuscles in the blood, and that this percentage steadily decreased until 

 the expiration of four days, when they had completely disappeared. The 

 disappearance of the foreign corpuscles was followed by the gradual 



