To the Editor of the Popular Science Monthly.
IT is interesting to contemplate that curious phase of credulity, closely allied to superstition, which seems to be innate in the human mind, predisposing many intelligent people to attribute to supernatural agencies certain phenomena which are purely subjective. This quality has, doubtless, contributed to the growth of faith in spiritualism, odylism, auras, psychic force, and what not.
One would suppose that the recent exposure in the law-courts of the juggleries of some of the more notorious mediums would have served to convince the most ardent believers that the so-called spirit-manifestations are wholly mundane. This good result, however, does not appear to have been accomplished as yet.
When "Professor" Brown, the mind-reader, performed his clever experiments a few years since, many well-educated people maintained that his discoveries could not be explained by any of the known laws of Nature; he was indorsed by several distinguished scientists, at least one of whom stated that he was a firm believer in Brown, and that he regarded "the theory of unconscious muscular action as entirely opposed to the facts observed."
Since that time quite a number of articles have appeared in this and other scientific journals upon the subject; they have all been devoted to elaborating theories, and I propose, therefore, to confine myself to a few practical hints as to the precise methods of observation, hoping thereby to enable persons interested to perform all of Mr. Brown's experiments successfully, as well as others of a more complex and astonishing character, and, at the same time, to answer numerous queries that I have from time to time received.
The main difficulty that the novice in the art of interpreting "ideo-motor movements" encounters is, that he does not know exactly what indications to look for, and often mistakes an accidental or intentional movement of the "subject" for an involuntary one. He also imagines that the indications are confined to muscular contractions in the arm or hand of the subject. This is a fatal mistake, as I have already shown in a letter to Dr. Beard, which he communicated to your journal in the July number, 1877. In that letter I stated that it is quite possible for the mind-reader to select objects hidden or thought of, walk over any route desired, or to perform any similar experiment, without any connection between his subject and himself, even while he is blindfolded. I also referred to several other novelties, and shall now content myself with a simple explanation of the modus operandi upon which the whole principle depends; leaving it to the ingenuity of experimenters to complicate the tests according to their ability.
Let us suppose that the mind-reader has been escorted out of the parlor by a committee appointed by the guests to see that all is fair. A "subject" is then selected who will hide a small article, perhaps a pin, under the carpet in the corner of the room. The mind-reader is led in blindfolded, he takes the left hand of the subject in his left (à la Brown), grasping the subject's elbow with his right; he tells the subject to fix his mind intently upon the object hidden and the locality; he then makes a feint to move away, watching closely to see whether the subject shows any reluctance to follow him; if so, he tries another direction; presently he will find one point toward which the subject will show a disposition to accompany him very readily. This, then, is the first clew; he follows it up, occasionally feigning to diverge, in order to satisfy himself that he is on the right track. In this way he will be guided (not led) past all obstructions to the locality; then he will notice that the subject shows no partiality toward any particular direction. The mind-reader thus infers that he is, in juvenile parlance, very hot, and he now, for the first time, directs his attention exclusively to the involuntary movements in the arm of the subject, in order to obtain the indication as to the exact locality of the object hidden. This he accomplishes by moving the subject's arm about until he discovers the direction in which the arm unconsciously prefers to go. Should the subject suspect that he may be involuntarily giving the indications, it is a capital ruse for the performer, first, to satisfy himself of the position of the object, and, before producing it, to move away from the spot, then suddenly pounce upon it with great show of certainty. The "bull-dozed" subject will at once become the strongest opponent of the involuntary muscular-movement theory!
Apart from the amusement which these performances invariably afford at a social gathering, the subject of the "ideo-motor movements" is one of the highest physio-