In this case it will be observed that P. alone was in possession of the knowledge, without which all the efforts of those at the table could have produced only a meaningless sequence of letters. In some other experiments of the series the procedure was more complicated. M. Richet, standing apart from both tables, asked a question, the answer to which was given by the percipients with a certain approximation to correctness. The results, though less striking than those already quoted, are yet such as to suggest that they were not due to chance.[55]
Production of Local Anæsthesia.
We now pass to experiments of another kind, resembling those last quoted, inasmuch as the effects were produced without the consciousness of the percipient, but differing in the important particular that no deliberate and conscious effort on his part could have enabled him to produce them. In experiments carried on with various subjects at intervals through the years 1883-87, at some of which the present writer assisted, Mr. Edmund Gurney had shown that it was possible by means of the unexpressed will of the agent to produce local anæsthesia in certain persons. (S.P.R., vol. i. pp. 257-260; ii. 201-205; iii. 453-459; v. 14-17.) In these experiments the subject was placed at a table, and his hands were passed through holes in a large brown paper screen, so that they were completely concealed from his view. Mr. G. A. Smith then held his hand at a distance of two or three inches from the finger indicated by Mr. Gurney, at the same time willing that it should become rigid and insensible. On subsequently applying appropriate tests it was found, as a rule, that the finger selected had actually become rigid and was insensible to pain. In the last series of 160 experiments Mr. Gurney, as well as Mr. Smith, held his hand over a particular finger. In 124 cases the finger over which Mr. Smith's hand had been held was alone affected; in 16 cases Mr. Gurney and Mr. Smith were both successful; in 13 cases Mr. Gurney was successful and Mr. Smith failed. In the remaining 7 cases no effect at all was produced. It is noteworthy that in a series of 41 similar trials, in which Mr. Smith, while holding his hand in the same position, willed that no effect should be produced, there was actually no effect in 36 cases; in 4 cases the finger over which his hand was held, and in the remaining case another finger, were affected. The rigidity was tested by asking the subject, at the end of the experiment, to close his hands. When he complied with the request the finger operated on—if the experiment had succeeded—would remain rigid. The insensibility was proved by pricking, burning, or by a current from an induction coil. In the majority of the successful trials the insensibility was shown to be proof against all assaults, however severe.
In these earlier experiments it seemed essential to success that Mr. Smith's hand should be in close proximity to that of the subject, without any intervening barrier. These conditions made it difficult to exclude the possibility of the subject learning by variations in temperature, or by air currents, which finger was actually being operated on; though it is hard to conceive that the percipient could by any such means have discriminated between Mr. Gurney's hand and Mr. Smith's. On the other hand, even if this source of error was held to be excluded, the interpretation of the results remained ambiguous. As a matter of fact, Mr. Gurney himself was inclined to attribute the effects produced, not to telepathy, as ordinarily understood, but to a specific vital effluence, or, as he phrased it, a kind of nervous induction, operating directly on the affected part of the percipient's organism. (Proc. S.P.R., vol. v. pp. 254-259.)
With a view to test this hypothesis further experiments of the same kind were made by Mrs. Sidgwick during the years 1890 and 1892, the subjects being P. and Miss B. already mentioned. The percipient was throughout in a normal condition. As before, he sat at a table with his hands passed through holes in a large screen, which extended sufficiently far in all directions to prevent him from seeing either the operator or his own hands. Mr. Smith, as before, willed to produce the desired effect in the finger which had been intimated to him, either by signs or writing, by one of the experimenters. Passing over the trials, very generally successful, made under the same conditions as Mr. Gurney's experiments—i.e., with the agent's hand held at a short distance without any intervening screen from the finger selected—we will quote Mrs. Sidgwick's account of the later series performed under varied conditions. (Proc. S.P.R., vol. viii. pp. 577-596.)
No. 28.—By MRS. H. SIDGWICK.
In the second division, (b), of our experiments come those in which a glass screen was placed over the subject's hands. For the first four of these we used a framed window pane which happened to be handy. Then we obtained and used a sheet of 32 oz. glass, measuring 22 by 10 inches and 1⁄6 inch in thickness. This was supported on two large books placed beyond the subject's hands on each side, and in this position the upper surface of the glass was 2¼ inches above the surface of the table, so that there was ample room for the hands to rest underneath without touching the glass. Mr. Smith held his hand in the usual position over the selected finger, above the glass and not touching it. Under these conditions we tried 21 experiments with P., of which 18 were successful, and 6 with Miss B., all successful. In the case of the 3 failures with P., no effect was produced on any finger. In one successful case, the time taken was long, and we interrupted the experiment by premature testing in the way explained above.
Division (c) includes those experiments in which Mr. Smith did not approximate his hand to that of the subject at all, but merely looked at the selected finger from some place in the same room as the subject, but out of his sight. The distances between him and the subject varied from about 2½ to about 12 feet. Under these conditions we tried 37 experiments with P., 18 in 1890, of which 6 were failures, and 2 only partially successful, and 19 in 1892, of which 10 were failures. The proportion of success was, it thus appears, much less than under the previously described conditions, but still much beyond what chance would produce. Of the 6 failures in 1890, one was a case in which Mr. Smith made a mistake as to which finger we had selected, but succeeded with the one he thought of. In another case the left thumb instead of the right thumb became insensitive. In the other 4 cases no finger at all was affected.
Of the 10 failures in 1892, no effect was produced in 4 cases; in another the right (viz., the little) finger of the wrong hand became insensitive;[56] in 4 cases an adjoining finger was affected—once only slightly—instead of that selected, and in the remaining case a finger distant from the selected one was slightly affected.
Six experiments were made with Mr. Smith looking at the finger through the opera-glass at a distance of from 22 to 25 feet; in three cases the experiment succeeded, in three another finger was affected instead of that selected. Fourteen experiments were made with a closed door intervening between percipient and agent; 2 only succeeded, and in 8 a wrong finger was affected, no effect at all being produced in the remaining 4 cases. In a further series of 4 trials Mr. Smith held his hand near the percipient, and willed to produce no effect. The trials were successful. In all these experiments P. was the percipient.
The rigidity was tested, as before, by asking the subject to close his hands; the anæsthesia, as a rule, by touches or the induction coil. Tested by the latter means it was found, as the current was gradually increased to the maximum, that the insensibility was not always complete. Flexibility and sensation were usually restored, for economy of time, by means of upward passes; but a few trials made later in the series served to show that the finger could be restored to its normal condition by a mere effort of will on the part of the agent. In some cases when their attention was specially directed to their sensations the subjects were able to indicate beforehand the finger operated on, by reason of the feeling of cold in it. But as a rule they appeared to be unaware which finger was affected. It is perhaps needless to point out that no conscious effort on their part could have produced the results described.