contains neither starch, nor cellulose; but the albumin of the plant
is very similar to that of the animal, and the fibrin and syntonin of
the animal are bodies closely allied to both albumin and gluten.

That there is a close likeness between all these bodies is obvious
from the fact that when any of them is strongly heated, or allowed to
putrefy, it gives off the same sort of disagreeable smell; and careful
chemical analysis has shown that they are, in fact, all composed of
the elements carbon, hydrogen, oxygen, and nitrogen, combined in very
nearly the same proportions. Indeed, charcoal, which is impure carbon,
might be obtained by strongly heating either a handful of corn, or a
piece of fowl's flesh, in a vessel from which the air is excluded so
as to keep the corn or the flesh from burning. And if the vessel were
a still, so that the products of this destructive distillation, as it
is called, could be condensed and collected, we should find water and
ammonia, in some shape or other, in the receiver. Now ammonia is a
compound of the elementary bodies, nitrogen and hydrogen; therefore
both nitrogen and hydrogen must have been contained in the bodies from
which it is derived.

It is certain, then, that very similar nitrogenous compounds form a
very large part of the bodies of both the wheat plant and the fowl,
and these bodies are called proteids.

It is a very remarkable fact that not only are such substances as
albumin, gluten, fibrin, and syntonin, known exclusively as products
of animal and vegetable bodies, but that every animal and every plant,
at all periods of its existence, contains one or other of them,
though, in other respects, the composition of living bodies may vary
indefinitely. Thus, some plants contain neither starch nor cellulose,