"habu" venom and its serum therapy. 153 



supernatant fluid desiccated, it forms a brilliant yellow powder. The 

 amount of this fixed constituent is shown in the following- table : 



Locality from which snakes 

 came. 



Number 



of 

 snakes. 



Quantity 

 of venom 

 (cubic cen- 

 timeters). 



Dried 



(grams). 



Fixed 



substance 

 (percent). 



Average 

 quantity of 

 venom lor 

 one snake 

 (cubic cen- 

 timeter). 



Average 

 quantity 



dried 1 

 (gram). 





466 

 556 

 195 

 J IS 



71. -10 

 81.00 

 58.47 

 122. 10 



18.41 

 20.85 

 16.46 

 27.29 



25.8 

 25.7 

 28.2 

 22.4 



0. 153 

 0.115 

 0.299 

 0. 292 



0. 0395 

 0. 0375 

 0. 0844 

 0. 0653 



Do 









The dried venom is durable and it dissolves in water giving an opales- 

 cent solution with a slight precipitate ; it is also almost completely 

 soluble in glycerin, it coagulates at 75° C, and is precipitated by alcohol. 

 It presents all the reactions characteristic of proteids, clearly showing 

 Millon's and Vincent's reactions. It turns polarized rays to the left, 

 and shows no lines of absorption in the spectrum. 



Its chemical nature is not yet known clearly. The venom may be 

 brought down by any of the reagents which precipitate proteids. About 

 one-third of the original poison in a 1 per cent solution may be precip- 

 itated by adding alcohol to 33 per cent, and one-half of the whole amount 

 of the poison present in the original solution from the filtered fluid will be 

 precipitated by increasing the alcohol to 50 per cent. As more alcohol 

 is added, the amount of precipitation increases, but the amount of the 

 latter finally remains constant after the alcohol readies 75 per cent. 

 The greater part of the venom is precipitated if one-half the quantity of 

 ammonium sulphate necessary to form a saturated solution is added. 



RESISTANCE OF THE VENOM TO PHYSICAL AND CHEMICAL INFLUENCES. 



The fact that the resistance of snake venom to heat seems to vary 

 according to the species of snake from which it is collected has been 

 ascertained by Mitchell and Eeichert, Calmette, Physalix and Bertrand", 

 Flexner and Noguchi, Lamb, and Isliizuka. Habu venom presents no 

 change even though it is heated for thirty minutes at 60° C. A 1 per 

 cent solution, however, will precipitate a little by being heated for 

 fifteen minutes at 75° C, while its toxicity is reduced to one-tenth of 

 the original. The principle which causes extravasation when the venom 

 is injected is especially ^weakened, while the haemolytic and neurotoxic 

 constituents are scarcely affected. It loses nearly all toxicity if heated 

 for thirty minutes at 90° C. The toxicity of the venom is reduced to 

 one-tenth of the original strength by exposure to the direct sunlight 

 during six hours. 



