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 wooden support, below which is a coil of copper wire, which, however, is not connected with any battery or other apparatus, and merely serves to condense the current. Below the needle, inside the glass, there is a circular card divided into degrees to mark the action of the needle. Two of these instruments are placed side by side, but in no way connected, and the experimenter then holds out the fingers of both hands to within about an inch of the glasses. According to the theory, the current enters at the left hand, circulates through the body, and passes out at the right hand, that is to say, there is an indrawing at the left and a giving-out at the right, thus agreeing with Reichenbach's experiments on the polarity of the human body.