The Physiological action of Snake-venom.

BY

BRIGADE-SURGEON-LIEUTENANT-COLONEL D. D. CUNNINGHAM,

C. I. E., F. R. S.

        IN the course of a prolonged series of experiments, which were primarily
undertaken with a view of testing the efficacy of various reputed remedies for
cases of snake-bite, certain phenomena have presented themselves, appearing to
justify some conclusions in regard to the nature and physiological action of the
venom of Colubrine and Viperine snakes, which appear to be of sufficient interest
to merit publication, and it is accordingly proposed to draw attention to them in
the following pages. Certain of the conclusions are by no means new; but they
are, at the same time, not in accord with currently-accepted opinion, and, there-
fore, appear to be worthy of renewed discussion in the light of newly-recorded
facts, and, in any case, they have not been arrived at hastily, but as the result
of much experimental work.

        Any course of experiments on ordinarily reputed remedies for cases of
snake-bite is somewhat heartless work from the monotonously futile results
which it yields when regarded solely in the light of a quest for practical means
of contending with the action of snake-venom; but it possesses one great advan-
tage in enforcing the constant employment of minimal lethal doses of the latter
and, therefore, in affording opportunities for the accurate study of the precise
sequence of events occurring in the course of the intoxication,which are not present
in cases where relatively large doses enter the system, and where, consequently,
the progress of the symptoms is much more accelerated.

        Various factors would appear to have co-operated to give rise to misconcep-
tions in regard to the precise nature and the physiological action of snake-venoms.
The employment of excessive doses has, in many cases, served to obscure
details in the course of the intoxication by hurrying on the symptoms so rapidly
that their sequence could not be accurately followed; confusion has arisen from
comparing the results of the action of the venom in different cases in which no
precautions had been taken to secure any accurate parallelism in the proportions
of the doses to the weights of the recipient animals; the use of fresh venom,
and specially its introduction in the natural fashion by means of bites, has,
probably in some instances, led to the effects of the specific toxins being con-
founded with those of pathogenic organisms which may enter the system along
with them; and, finally, in so far as Viperine venom is concerned, errors have

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