458 Proceedings of Royal Society of Edinburgh. [sess. 
ters soon after entering the intestinal canal, and most probably, 
therefore, by the bile or the pancreatic secretion. 
To fully explain the innocuousness of stomach administration 
would accordingly require that the effects on venom of the biliary 
and other intestinal secretions should be investigated, and also the 
absorbability of venom through the intestinal walls. 
As a contribution to the settlement of the question, I have made 
a number of experiments with the biliary secretion ; and whatever 
may be the influence of the other secretions or of intestinal absorp- 
tion, that of the bile has been found to be so decided as to be 
in itself sufficient to account for the innocuousness of stomach 
administration. 
The bile from the gall-bladder of the African cobra, puff-adder, 
rattlesnake, and grass snake was used, and each bile was tested 
against the venom of the African and the Indian cobra.* For the 
most part, the experiments were made by mixing various quantities 
of each bile with a little more than the minimum-lethal dose of the 
venom, and then injecting this mixture under the skin of the 
animal. The object of the experiments was not only to determine 
if the bile can render venom innocuous, but also, if it have this 
power, what is the smallest quantity of bile capable of doing it. 
As bile varies much in its concentration, it was always weighed in 
the dry farm, so as to remove avoidable fallacies in dosage and in 
any comparison that might be made between the bile of different 
animals. 
Taking first the venom of the African cobra, its minimum-lethal 
dose for rabbits was determined and found to be *000245 grm. 
p. kilo., but a slightly larger dose — viz., '00025 grm. — was taken 
as the minimum-lethal. 
The experiments were made by mixing together and leaving in 
contact with each other for ten minutes this dose of venom with a 
dose of bile, each substance having been dissolved in a few lOths 
* For supplies of dried serpents’ bile I am indebted to Mr J. W. van Putten, 
of Brakfontein, South Africa, who has sent me (April and June 1895, and 
December 1896) the bile of the African cobra, puff-adder, and night-adder ; 
and also to Mr J. H. V. Payne, of Hout Bay, Cape Colony, from whom I 
have received (December 1896) the bile of the puff-adder. The rattlesnake 
bile was taken by me from a living snake, more recently presented by Pro- 
fessor Malcolm Laurie, of St Mungo’s College, Glasgow. 
