460 REPORT OF NATIONAL MUSEUM, 1893. 



of temperature, but that it is still toxic even when boiled; Dr. Wall's 

 experiments,* as quoted by Woltenden, seem to show that cobra 

 poison resists the heat even better, for it is stated that prolonged 

 application of heat (for two hours) at a hiuh temperature at last 

 destroys the toxicity of cobra venom, and that a dilute solution is 

 more easily destroyed by heating than a strong, such a toxic dilute 

 solution being destroyed aft?" heating at 10!>° O. for half an hour. 



When exposed to the air, even for a short time, the fluid poison takes 

 up bacteria, and putrefaction proceeds particularly rapid if the venom 

 be diluted with water. Continued alteration of this kind finally appears 

 to destR\y its toxicity. 



Excluded from the air, however, or preserved in pure alcohol or 

 glycerine, the venom retains its properties for almost any length of 

 time, as shewn by the fact that a glycerine solution in the possession of 

 Dr. Mitchell for twenty years was still toxic. 



Dried and kept from atmospheric humidity it is equally permanent, 

 twenty-two years not being able to alter it in the least. It is there- 

 fore advisable to handle the dried isolated fangs of the large venomous 

 snakes with caution. It dries somewhat like a gum or varnish, and 

 will crack and scale off in a similar manner. 



In discussing the chemical characteristics of snake poison, it is 

 hardly necessary at the present day to refer to the now thoroughly 

 refuted theories of the crystalline nature of any of its active toxic con- 

 stituents. The last attemi)t (that of A. Wynter Blyth) t to prove the 

 poisonous quality of the cobra venom to be due to a certain " cobric 

 acid" was effectually disposed of by Dr. K. IsTorris Wolfenden,| and 

 need not detain us here. 



There are, on the other hand, still some physiologists who are not 

 satisfied that the negative results obtained by Prof. Wolcott Gibbs at 

 the request of Drs. Mitchell and Reichert in their search for alkaloids in 

 the venom of the rattlesnake are absolute conclusive, in view of Dr. 

 Armand Gautier's positive determination of leucomaines or alkaloids 

 derived from living protoplasm in snake poison. In his much discussed 

 article, " Sur les alcaloi'des derives de la destruction bacterienne ou 

 physiologique des tissus animaux,"§ Gautier positively affirmed his 

 assertion of 1881 (Bull. Ac. Med., Paris (2 ser.), x, 1881, pp. 947-953, 

 and discussion following, pp. 953-958) that from the venom of a Trigo- 

 noceplialus, and particularly from that of the cobra, he had been able 

 to extract a small (juantity of matter belonging to the organic alkalis. 

 From the cobra poison he prepared two new alkaloids, which, among 



* Indian Snake Poisons, 1883 (pp. 120-124). 



t The Poison of tlie Cobra de Capello. Analyst, i, London, 1877, pp. 204-207. 



t On 'Cobric Acid,' a so-called constituent of cobra venom. Journ. Physiol., 

 Cambridge, vii, 1886, pp. 365-370. 



^ Bulletin de I'Academie de Medecine, Paris (2 ser.), xv, 1886, pp. 65-97 : i part. 

 Alcaloi'des bact6rienues ou ptomaines ; pp. 115-139: iipart. Alcaloides physiologiques 

 ou leucomaines. 



