ed laws of combination that Liebig is
unwilling to admit the new force at all to which Berzelius had given the
name so generally accepted.

The phenomena of isomerism, or identity of composition and proportions of
constituents with difference of qualities, and of isomorphism, or
identity of form in crystals which have one element substituted for
another, were equally surprises to science; and although the mechanism by
which they are brought about can be to a certain extent explained by a
reference to the hypothetical atoms of which the elements are
constituted, yet this is only turning the difficulty into a fraction with
an infinitesimal denominator and an infinite numerator.

So far we have studied the working of force and its seeming anomalies in
purely chemical phenomena. But we soon find that chemical force is
developed by various other physical agencies,--by heat, by light, by
electricity, by magnetism, by mechanical agencies; and, vice versa, that
chemical action develops heat, light, electricity, magnetism, mechanical
force, as we see in our matches, galvanic batteries, and explosive
compounds. Proceeding with our experiments, we find that every kind of
force is capable of producing all other kinds, or, in Mr. Faraday's
language, that "the various forms under which the forces of matter are
made manifest have a common origin, or, in other words, are so directly
related and mutually dependent that they are convertible one into
another."

Out of this doctrine naturally springs that of the conservation of force,
so ably illustrated by Mr. Grove, Dr. Carpenter, and Mr. Faraday. This
idea is no novelty, though it seems so at first sight. It was maintained
and disputed among the giants of philosophy. Des Cartes and Leibnitz
denied that any new motion originated in nature, or that any ever ceased
to exist; all motion being in a circle, passing from one body to another,
one losing what the other gained. Newton, on the other hand, believed
that new motions were generated and existing ones destroyed. On the
first supposition, there is a fixed amount of force always circulating in
the universe. On the second, the total amount may be increasing or
diminishing. You will find in the "Annual of Scientific Discovery" for
1858 a very interesting lecture by Professor Helmholtz of Bonn, in which
it is maintained that a certain portion of force is lost in every natural
process, being converted into unchangeable heat, so that the un