It is done by Mollusks. We can tell you even the precise kind--it is the
Gasteropod kind. Not only this, we know the very devil himself that does
it. (And you will say that "devil" is not a particle too rough a term,
when we come to tell what it is he "secretes.") It is the _Dolium
galea_, good friends, and we could tell you six other kinds that are
suspected of this meanness. One of 'em is the _Pleurobranchidium_
--which, of course, you have often heard of.
Well, what do these wretched Mollusks go and secrete? We can tell
you--we, who know everything. It is sulphuric acid! What! do they steal
it? Oh, no; they "evolve" it--probably from the "depths of their own
consciousness."
And what do they do it for? Well, they bore with it. Give 'em a chance,
and they'll go through _you_. The acid eats its way, and then they eat
_their_ way. That way is not ours, exactly; but we have known human
beings about as venomous as this creature, and with precisely the same
tendency to pierce one. They do it with their tongues, it is true, but
the perforation is complete.
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