Medical Officers of the Army of India.

49

clusions states at one place definitely and unreservedly,¹that "the poisonous
snakes are not affected by their own poison," yet, he notes on the following
page that, although "in many of the various experiments I have performed,
the Cobra, Daboia, and Krait did not appear able to poison themselves or each
other, some of the experiments render this doubtful. "

     And Richards, although noting²that "I believe one cobra cannot poison
another" and³"I am quite satisfied the cobra cannot kill another cobra;"
and recently⁴he relates how healthy cobras, which he kept together in captivity,
would "very often on the slightest provocation begin to fight in a most savage"
fashion, biting each other fiercely, with the result that "neither of the combat-
ants ever seemed any the worse for the fight." Yet, he notes,⁵"I came to the
conclusion, after numerous experiments, that one species of snake could kill
another" (by the context) venomous snake of the same species.⁶

Desirability of further investiga-
tion.

     Such conflict of opinion upon so elementary a point rendered a further
investigation of the subject desirable—especially,
as the methods adopted by several of the foregoing
experimenters, to elucidate the point at issue, were open to objection.

Part I.—Working Scheme adopted.

Scope of inquiry defined.

     The inquiry resolves itself into a consideration of the effect of venom
⁽¹⁾upon the serpent itself and its own species, ⁽²⁾upon
venomous snakes of other species, ⁽³⁾upon innocent
snakes, ⁽⁴⁾upon other reptiles and cold-blooded animals, ⁽⁵⁾upon warm-blooded
animals; and of the topics arising out of the results of the above investigations.

Sources of experimental error.

     It is claimed for the present series of experiments that they have avoided
many of the sources of experimental error to which
those of former observers were liable:—

Injury to viscera, &c., during
infliction of bite.

     The method usually employed to ascertain the toxic effect of snake-venom
upon snakes had been to force one snake to bite
another, or its own tail. In this way, however, there
is always a probability that the spine or viscera of the bitten snake were crushed,
or otherwise grossly injured during the act of biting.⁷

Uncertain introduction of venom
by biting.

     Again, in employing biting as a means of introducing venom, there is un-
certainty as to the amount of venom introduced;
and in some cases uncertainty as to whether any
venom at all has been injected—owing to the want of anatomical continuity

1loc. cit., p. 64.

2idem, p. 126.

3idem, p.127.

4Landmarks of Snake-poison Literature. 2nd Ed. Calcutta, 1886, p. 12.

5idem, p. 12.

6No details of the experiments are given.

7In Fayrer's series of cobras-bitten-by-cobras no post-mortem examination appears to have been made
to ascertain whether any such fatal injury had been inflicted.

H