HOW TO COLLECT SNAKE VENOM. BVH 
two or three months, yield an average of four or five drops of 
venom. Sometimes only a drop or two can be obtained. I 
have noticed that when a snake makes a full bite on a living 
animal, usually no poison oozes out of the punctures. The 
reason is that the venom is driven into the tissues with great 
force, and at the same time the punctures are plugged by the 
fangs, consequently the venom spreads out into the tissues 
around the wounds. This being so, it is desirable, if an attempt 
is being made to suck out the poison by mouth suction, that the 
flesh be previously well scarified over the site of the punctures. 
Of course, while the knife is being got ready, the punctures 
should be sucked meanwhile, as this retards the absorbing power 
of the capillary blood vessels and lymphatics, which lie in a 
thick network under the skin and among the muscles. 
Snake venom is slightly acid. Sometimes it is found to be 
more or less alkaline. This is due to admixture with the secre- 
tions of the mouth. Cobra venom is intensely bitter. Viper 
venom is more or less tasteless. The specific gravity of Cobra 
venom, according to Martin, averages 11°10 ; that of the Daboia 
(Indian Adder), 10°77. The amount of solids contained in these 
two venoms corresponded with the specific gravity—the per- 
centage of solids in Cobra venom averaged 31°5 and in the poison 
of the Daboia 244. C. J. Martin states that the variations are 
considerable in the case of the Cobra, being from 23 to 38 per cent. 
Pure venom, when examined microscopically, reveals nothing. 
If it be contaminated with the fluids of the snake’s mouth, 
salivary corpuscles, bacteria, and epithelial cells are seen. 
Snake venom, if kept in solution with pure glycerine or in a 
dry condition, will keep indefinitely. Cobra venom, when dry, 
presents a cracked appearance like gum and looks like little 
yellowish scales. Viper venom cracks up into needle-like pieces 
which radiate from the centre of the dry mass of venom. When 
scraped up it has the appearance of yellow sugar. 
EFFECT OF THE VENOM OF ONE SNAKE UPON OTHER SNAKES. 
The venom of the Puff Adder apparently has no poisonous 
effect upon those of its own kind or species. I have frequently 
forced adult Puff Adders to bite themselves without any ill- 
effects. I have injected Puff Adder venom into others of the 
