e Bon proved that, by
producing artificial equilibria of the elements arising from the
dissociation of matter, he could succeed in creating, with immaterial
particles, "something singularly resembling matter." These equilibria
were maintained a sufficient length of time to enable them to be
photographed.

On p. 164 of Dr. Le Bon's _Evolution of Matter_, are to be found
photographs of what is practically materialized matter. This author
says, in part:--

"Such equilibria can only be maintained for a moment. If we were
able to isolate and fix them for good--that is to say, so that they
would survive their generating cause--we should have succeeded in
creating with immaterial particles something singularly resembling
matter. The enormous quantity of energy condensed within the atom
shows the impossibility of realizing such an experiment. But, if we
cannot with immaterial things effect equilibria, able to survive
the cause which gave them birth, we can at least maintain them for
a sufficiently long time to photograph them, and thus create a sort
of momentary materialization."

If, therefore, physical science now admits, as it does, that
vibrations, or disturbances in the ether, can be photographed, there is
no longer any _a priori_ objection to these experiments by Dr.
Baraduc--which claim, merely, that similar vibrations have been
photographed--such vibrations being the external modification or
impression left upon the ether by the causal thought.

So much for theoretical possibilities: now for the facts.

In a remarkable little booklet, entitled, _Unseen Faces Photographed_,
Dr. H. A. Reid has presented a number of cases of supposed spirit
photography, some of which are certainly difficult to account for by any
theory of fraud. It is true that the methods of imitating this process
by fraudulent means are numerous and ingenious; but practically none of
them are unknown. In _The Physical Phenomena of Spiritualism_, pp.
206-23, I have described these fraudulent methods in considerable
detail; and have also published an account of a case in which trickery
was actually detected in the process of operation. (See _Proceedings of
the American S.P.R._, 1908, vol. ii., pp. 10-13.) But there seem to be
certain cases on record that are most difficult to account for by any
theory of trickery--partly because of the excellence of the conditions,
and partly because of the character