EFFECTS OF SNAKE VENOM. 359 



the venom caused almost instant paralysis of the motor nerve 

 centres. After death, little or no alteration to the blood could 

 be detected. 



It must, however, not be inferred that the cat is as strongly 

 immune to all venoms, for cats bitten by Cape Cobras died in 

 fifteen to twenty minutes. 



Snakes kept in captivity, unless under strictly natural con- 

 ditions out-of-doors, and in their native country, do not thrive, 

 and their venom becomes less in quantity although not usually 

 poorer in quality. I have noticed that snakes which have been 

 subjected to different climatic conditions to those of their native 

 habitat deteriorate the most. In fact, they invariably refuse all 

 food and die in a short time. Some species of snakes are so 

 susceptible to a sudden change of environment that they perish 

 in a month or so, although the temperature of the air be main- 

 tained at that of their native haunts. 



Effects of Snake Venom. 



According to Eraser, about 30 mgrms. (about half a drop) of 

 Indian Cobra venom is sufficient to kill a man. This means that 

 a full-sized Cobra would be able to eject enough venom at a 

 single full and complete bite to kill about twenty men. 



Dr. Hanna and others state that the Indian Cobra yields as 

 much as twenty drops of venom. Dr. Hanna mentions having 

 obtained as much as twenty-eight drops. 



In experiments with the venom of the Cape Cobra I found 

 that one drop diluted in a little water and injected into the 

 tissues of the leg of a large monkey killed it in half an hour's 

 time. A fraction of a drop was sufficient to kill a rat and 

 a fowl within half an hour. One drop was sufficient to kill 

 adult Chacma Baboons within one hour. Judging from the 

 effects of Cobra venom on the higher animals such as monkeys, 

 I consider that one full drop is a fatal dose for a strong 

 healthy man. This fact makes the treatment of snake bite a 

 most complicated one. It will clearly be seen that if a Cobra or 

 Mamba should succeed in delivering a full bite, many times a 

 fatal dose is hkely to be injected; therefore, in spite of prompt 

 applications of permanganate of potash, ligatures and the 

 injection of serum, the victim might die. The only hope in these 

 cases is the copious intravenous injection of anti-venomous serum. 



