Theosophists and
certain Mystics and Occultists, _that_ is a question which we cannot at
present answer, and for which we may have to wait for several hundred
years before one can be satisfactorily given.

But, granting the reality of the phenomena, they themselves demand
solution, solely from the point of view of physics and physiology, and
quite aside from the nature of the intelligence with which they are at
times associated. The facts themselves still need elucidation.

Some years ago a gentleman of my acquaintance started out with the
intention of constructing a telephone by means of which it would be
possible to speak directly to the spirit world! He had in mind great
delicacy of apparatus, a system of "relays," by means of which it would
be possible to augment an initial stimulus, however slight, a magnifying
apparatus which would greatly increase the volume of sound, on the lines
of the ampliphone and the microphone, etc. I do not believe that very
definite results were ever achieved, and he is still at work upon the
problem. Needless to say, this idea of his was ridiculed in all
quarters; but I myself do not see any valid reason why some such device
should not succeed--provided, of course, that a spiritual world exists
at all. If such a world exists, if the intelligences which reside
therein can at times produce physical phenomena, then it is certainly
conceivable that some energy may be set into operation which may produce
the desired results--some energy which we, too, can utilize and which
the spiritual entity can also manipulate; in other words, _an energy
common to the two worlds_. Were such a common medium or mediator found,
communication would certainly be established, and it only remains for us
to discover the common energy. Personally, I believe that this
intermediary is most probably _vitality_--the life-force, without the
presence of which such manifestations would be impossible. A living,
human being is necessary, upon whose presence these phenomena depend,
and without whom they could not occur. It is thus obvious that there is
a definite connection between these phenomena and _life_, which can
hardly be due to chance; it must stand in some intimate and causal
relation.[9]

14. Many students of psychical phenomena believe that, in the case of
Eusapia Palladino, e.g., this connection is clearly discernible, and
that it is upon the externalization of her vital force that many of
these phenomena de