A telegraphic key (b) was connected by wires (a,a) to a battery (d) and to two screws, connecting them with an electro-magnet (e) to the opposite end of which was attached a needle. The point of the needle touched a revolving drum (f), with a smoked surface, driven by two interlacing, cogged wheels. The whole of this registering apparatus was enclosed under a glass bell-jar (g). The telegraphic key itself (b) was covered by a cardboard box (c). The "powers" manifesting were asked to press the telegraphic key without tearing the cardboard box (that is, through it). When the key was depressed, this would be instantly communicated to the electro-magnet, and cause the needle to oscillate,—these oscillations being marked upon the smoked surface of the revolving drum. A number of successful tests were conducted by means of this apparatus.
A variation of this was then employed (Fig. 2). A cylinder filled with water (a) was connected by means of tubing (b) to a U-tube, or manometer (c), filled with mercury. Upon the further side of this tube floated a bent wire (e) inserted into a small cork. The point of this wire, again, was so adjusted as to come into contact with the smoked surface of a revolving drum (f), driven as before. The top of the cylinder (a) was covered with a rubber cap (d), and this whole apparatus was inserted under a wooden box (g) having a cloth top.
Now, if the rubber covering (d) were pressed upon, this would force some of the water, in a, along the tube, b, and the added air-pressure would depress the column of mercury in the manometer, causing the floating needle to rise on the opposite side, and scratch upon the revolving drum. Fig. 3 shows some of the tracings which were obtained in this way—the force acting through the cloth top, g.
The instruments thus recorded a definite physical, intelligent force.
It may interest my readers to know that, at the time of his death, M. Curie,—who had been completely convinced of the reality of these phenomena,—was busy devising an instrument which would register and direct psychic power liberated from the body of a physical medium when in trance.
Dr. Imoda, the assistant of Professor Mosso, has also conducted a number of experiments in the discharge of an electroscope, by means of "rays" issuing from the medium's body. It was found that, if the medium held her fingers at a distance of an inch or so from the knob of the electroscope, some form of energy, apparently radio-active in character, issued from her fingers, and gradually discharged the electroscope. This is the "radiation" or "emanation" issuing from the body, which has been studied extensively by students of the occult. Dr. Imoda concluded—as the result of his experiments—that "the radiations of radium, the cathode radiations of the Crookes' tube, and mediumistic radiations are fundamentally the same."
Some other very interesting facts have been observed by means of the electroscope. For example, Dr. W. J. Crawford (D.Sc), in his experiments, noted that:—
"... In séance rooms where tables are moved without physical contact, I found that after a sitting was well started, I was always unable to charge an electroscope, even though I tried to do so in the corner of the chamber farthest from the medium. In order to charge it I had to take it outside the room. I asked the 'operators' (intelligences 'directing things,' apparently, in the séance-room) if there was any 'power' in the séance-room so far away from the medium, and they answered in raps that there was. By 'power' I understand them to mean particles of matter taken from the medium...."