241 



PAirr 111. 

 AXTIVEXOMOUS SERUM TIIEEArEUTICS. 



CHAPTER XIII. 



VA CCINA TION A GAINST SNA KE- VENOM — PBEPAEA- 

 TION OF ANTIVENOMOUS SERUM— ITS PREVEN- 

 TIVE PROPERTIES AS REGARDS INTOXICATION 

 BY VENOM. 



So long ago as the year 1887 it was shown by Sewall, in an 

 important paper on "Rattlesnake-Venom/'^ that it is possible to 

 render pigeons gradually more resistant to the action of this venom 

 by injecting them with doses at first very small, and certainly 

 incapable of producing serious effects, and then with stronger and 

 stronger doses. In this way, although these little animals are very 

 sensitive, he succeeded in making them withstand doses ten times 

 greater than the minimal lethal dose. 



A little later Kaufmanm obtained the same result with the 

 venom of French vipers. He did not, however, succeed in pro- 

 ducing tolerance of doses more than two or three times greater 

 than the lethal one. 



In 189'2, at the time of my first experiments with cobra- venom 

 at Saigon,'' I arrived at the conclusion that it was possible, by 



' Journal of rhijsiologij, vol. Aiii., 1887, }). 203. 

 - " Les Viperes de France," p. 136 (1889). 

 ■' Annales de VInsiitut Pasteur, 1892, p. 181. 



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