241 
PARC IIT. 
ANTIVENOMOUS SERUM THERAPEUTICS. 
CHAPTER XIII. 
VACCINATION AGAINST SNAKE-VENOM — PREPARA- 
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 Kaufmann? 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 1892, at the time of my first experiments with cobra-venom 
at Saigon,’ I arrived at the conclusion that it was possible, by 
' Journal of Physiology, vol. viii., 1887, p. 203. 
? “ Les Vipères de France,” p. 136 (1889). 
* Annales de l’Institut Pasteur, 1892, p. 181. 
16 
