That such a connection must exist is proved by metaphysical argument in
answer to the question, "How did anything ever come into existence at all?"
And the whole creation, ourselves included, stands as evidence to this
great truth. But to many minds merely abstract argument is not completely
convincing, or at any rate it becomes more convincing if it is supported by
something of a more concrete nature; and for such readers I would give a
few hints as to the correspondence between the physical and the mental. The
subject covers a very wide area, and the limited space at my disposal will
only allow me to touch on a few suggestive points, still these may be
sufficient to show that the abstract argument has some corresponding facts
at the back of it.

One of the most convincing proofs I have seen is that afforded by the
"biometre," a little instrument invented by an eminent French scientist,
the late Dr. Hippolyte Baraduc, which shows the action of what he calls the
"vital current." His theory is that this force, whatever its actual nature
may be, is universally present, and operates as a current of physical
vitality perpetually, flowing with more or less energy through every
physical organism, and which can, at any rate to some extent, be controlled
by the power of the human will. The theory in all its minutiae is
exceedingly elaborate, and has been described in detail in Dr. Baraduc's
published works. In a conversation I had with him about a year ago, he told
me he was writing another book which would throw further light on the
subject, but a few months later he passed over before it was presented to
the world. The fact, however, which I wish to put before the reader, is the
ocular demonstration of the connection between mind and matter, which an
experiment with the biometre affords.

The instrument consists of a bell glass, from the inside of which is
suspended a copper needle by a fine silken thread. The glass stands on a