638 BEPTILES AND AMPHIBIANS. 



less, and if, after filtration, alcohol be added to the liquid part another 

 precipitate will be obtained, containing all its virulent property. The 

 material to which its virulence is due is, therefore, not precipitated by 

 heat, but is by alcohol, and yet this re-agent does not render it inert, as 

 has been shown by injecting the alcoholic precipitate under the skin of 

 animals. 



In the treatment of venomous snake-bites it is obvious that any means 

 taken to prevent the poison gaining full egress into the system must be 

 very serviceable. Thus, if the bitten part be a limb, a ligature above 

 the wound will interrupt the circulation and exclude a large portion of 

 the venom. For a similar purpose, scarifying or sucking the wound, or 

 burning it with caustics maybe of service. However, any such means to 

 be available must be used speedily after the injury, and their value 

 lessens as we recede from that period. As the venom is supposed to 

 operate by depressing the heart and inducing putrefactive changes in 

 the blood, muscles, and other parts of the system, it is evident that stimu- 

 lants are always indicated, and in fact, alcohol in some of its forms is 

 among the best remedies ; also bathing the wound in ammonia, and 

 ammonia and arsenic internally given, are said to have excellent anti- 

 dotal effects. ' 



After all, the danger from serpent bites, though serious, is not so bad 

 as is generally believed; In the first place, they are of rare occurrence, 

 and it is only exceptionally that we know of a person who has met with 

 such an accident ; and then in the second place, it is exceptional for a 

 person bitten by a venomous serpent to die. The rule is for them to get 

 well. In Dr. Mitchell's sixteen cases there were only four deaths, and 

 this is a fair average mortality. The danger, of course, varies with the 

 amount of poison injected, and the surgical means used to prevent its 

 complete passage into the system. The belief that hogs are not injured 

 can probably be explained on the ground that the virulent matter is ab- 

 sorbed by the adipose tissue and does not enter the circulation. 



The question of the virulence of the venom upon the serpent itself 

 has been settled by experiment, and also by Dr. Dearing's* case of a 

 Orotalm that accidentally bit himself. The result was the death of the 

 snake. Thus we see that the venom exerts its deadly power, not only 

 upon cold and warm-blooded vertebrates, but upon the animal which 

 produces it In other words, it is a liquid secreted from the blood, which 

 becomes fatal on being introduced back into the very same source. 



Another interesting fact in regard to these animals, to which, I believe, 



*Proo. Boston Soc. Nat. Hist., vol. iv, p. 313. 



