3. About twenty-five years ago, when the old phenomena of the oscillations of suspended buttons, developed by Dr. H. Mayo into a pseudo-scientific theory of od-force, were strongly exciting public attention, a medical friend of great intelligence, then residing in the south of France, wrote me long letters giving the results of his surprising experiences, and asking what I regarded as their rationale. My reply was simply, "Shut your eyes, and let some one else observe the oscillations." In a short time I heard from him again, to the effect that his reinvestigation of the matter under this condition had satisfied him that there was no other agency concerned than his own involuntary muscular movement, directed by his mental expectancy of the results which would ensue.
In the foregoing cases, the honest beliefs of the agents themselves brought about the results; in the following these beliefs were taken up by the witnesses to the performances of others, in spite of all common-sense probability to the contrary, under the influence of their own strong "prepossessions."
4. At a spiritualistic séance at which I was present, at an early stage of the present epidemic, the "medium" pressed down one side of a large loo table supported on a pedestal springing from three spreading feet, and left it resting on only two of its feet, with its surface at an angle of about 45°. Having been admitted to this séance under a promise of non-interference, I waited until its conclusion; and then, going over to the table, set it up and left it in the same position. For I had observed, when this was done by the "medium," that the edge of the broad claw of each foot, and the edge of its castor, bore on the ground together, so as to afford a base which, though narrow, was sufficient for the table to rest on, its weight happening to be balanced when thus tilted half over. Several persons of great intelligence who were present at this séance (Mr. Robert Chambers among the rest) assured me that, if it had not been for my exposure of this trick, they should have gone away in the belief that the table was sustained by "spiritual" influence, as in no other way could they suppose it to have kept its position against the force of gravity.