matter is
atomic. That being granted, when the statement is made, therefore, that
Aether is matter, the only logical conclusion that can be arrived at,
with reference to the question of the atomicity of the Aether, is, that
Aether is also atomic. Unless this be conceded, we have the first and
second rules of our Philosophy violated, as an atomless Aether is
opposed to that simplicity of conception, which is an essential
requirement of all hypotheses, and is moreover contrary to that
presumptive evidence gathered from observation and experiment, which
teaches us that all matter is atomic. If it be argued, that it is
impossible to decide upon a question as to the atomicity of the Aether,
my reply is that the same argument may reasonably be applied to all
matter. But, as Professor Rucker stated, all the evidence on matter
points out and supports the theory of its atomicity, and, therefore, the
only logical and philosophical conclusion is, that Aether is atomic
also. Again, it may be suggested that we cannot see or touch an atom of
Aether, and that it is not only invisible, but apparently incapable of
being made sensible to our senses. In reply to that, as I have already
shown in Art. 31, that objection can be equally used against an atom of
hydrogen, or an atom of oxygen. Does any one doubt the existence of the
hydrogen atom or the atom of oxygen, because it is invisible to the
sense of sight, or cannot be revealed to the limited sense of touch?
Certainly not! By the same reasoning, it is just as illogical to deny
the existence of an atom of Aether because it cannot be seen or felt, as
it is to deny the existence of an atom of hydrogen or oxygen. An atom of
Aether reveals itself to the senses in the same way that an atom of
hydrogen or oxygen does, that is, by the force or energy which it
exerts. Its vibrations can be manifested to the body in the form of
heat, while the undulatory motion which the aetherial atoms transmit in
the form of light, reveal the presence of the aetherial atom to the
sense of sight. The question at once arises as to what constitutes an
aetherial atom, what are its properties and motions?

Now, in order for us to enter successfully into this speculative region,
it is essential that we should, as far as possible, conform to the Rules
of Philosophy, and endeavour to gain some conception of an aetherial
atom from the results of experience and observation. In doing this, we
are at once confronted with