VACCINATION AGAINST SNAKE-VENOM 



245 



cuinb in coiu'se of treatment from endocarditis or acute nephritis ; 

 in the case of others, each injection of venom leads to the forma- 

 tion of enormons aseptic abscesses, which have to he opened 

 and drained. It may be said that on an average an interval of 

 aixteen months is necessary ui order to obtain a serum sufficiently 

 antitoxic. 



Pig. 94. — A.SEPTiCALLY Bleeding a Horse A'accinated against Venom in oiidee 

 TO obtain Antivenomous Serum at the Pastedr Institute at Lille. 



When a horse is well vaccinated and tolei'ates without a reaction 

 2 grammes of fdry-cobra-venona in a single subcutaneous injection, 

 it may be bled on three consecutive occasions in the space of ten 

 days, and in this way 20 litres of blood may be drawn from it 

 (fig. 94). 



