"At the time of her last sojourn in Paris (1906), I was able to obtain from Eusapia three séances at my house. I besought one of the keenest observers that I know, M. Dastre,—a member of the Academy of Science and professor of physiology at the Sorbonne,—to be kind enough to be present at our experiments. There were present also my assistant, M. Michaux, and the lady to whose kind offices I owe the presence of Eusapia.
"Besides the levitation of the table, we several times, and almost in full light, saw a hand appear. At first it was about two inches and a half above Eusapia's head, then at the side of the curtain which partly covered her, about twenty inches from her shoulder.
"We then organized, for the second séance, our methods of control. They were altogether decisive. Thanks to the possibility of producing behind Eusapia an illumination which she did not suspect, we were able to see one of her arms, very skilfully withdrawn from our control, move along horizontally behind the curtain and touch the arm of M. Dastre, and another time give me a slap on the hand.
"We concluded from our observations that the phenomena observed had nothing supernatural about them.
"As to the levitation of the table,—an extremely light one, placed before Eusapia, and which her hands scarcely left,—we have not been able to formulate any decisive explanation. I will only observe that Eusapia admitted that it was impossible for her to displace the slightest one of the very light objects placed upon that table."
After writing this note, M. G. Le Bon said to me verbally that, in his opinion, everything in these experiments is fraud.
[28] To these eight séances I might add a ninth, which took place on the succeeding December 5, in the study of Prof. Richet. Nothing remarkable occurred, unless it was the inflation, in full light, of a window curtain, which was about twenty-four inches from Eusapia's foot, my foot and leg being between it and her. The observation was absolutely accurate.
[29] To what cause may we attribute the levitation of the table? We have undoubtedly not yet discovered the secret. The action of gravity may be counterbalanced by movement.
You can amuse yourself, while at breakfast or dinner, by toying with a knife. If you hold it vertically in your tightly closed hand, its weight is counterbalanced by the pressure of the hand and it does not fall. Open your hand, still holding the knife grasped by the thumb and index finger, and it will slide as if it were in a too large tube. But move the hand by a rapid see-saw movement, from left to right, from right to left: you will thus create a centrifugal force which holds the object in vertical suspension, and which may even toss it above your hand and project it into the air, if the movement is rapid enough.
What, then, sustains the knife, annihilates its weight? Force. Might it not be that the influence of the experimenters seated around the table puts in special movement the molecules of the wood? They are already set in vibration by variations of temperature. These molecules are particles infinitely small which do not touch each other. Might not a molecular movement counterbalance the effect of gravity? I do not present this as an explanation, but as an illustrative suggestion (comme une image).