Vandermeulen Spirit Indicator

One of various devices invented to facilitate communication with spirits through mechanical means. It consisted of two glass prisms—one plain, the other resinous—fixed face-to-face on a board. Between them hung a very light triangle of wire. The prisms were connected to the positive and negative poles of a dry bell battery.

If the hanging triangle swung out and touched the positive wire, the circuit was closed and the bell rang. The spirits were expected to generate electricity in the prisms. If this was done, the hanging triangle wired to the negative pole would be repelled by the negative prism and attracted to the positive wire. The bell would ring, which was taken as an indication that a spirit desired to communicate, and the observers would rush to the ouija board to obtain the message.

The young inventor died in 1930 before his apparatus could be tested properly, but it was revived by a Mr. Rutot, a Belgian professor and a member of the Royal Academy of Sciences. Rutot claimed that by means of the apparatus he had been able to contact the dead inventor. The apparatus, which came to be known as Rutot's Spirit Indicator, was described in Revue Métapsychique (May-June, 1930, p. 256), and Rutot's own experiences were published in the Bulletin du Conseil de Recherches Métapsychiques de Belgique (July 1930). An English-language description of the apparatus, with detailed instructions for construction, was published by Robert J. Strong in his book Spiritual Engineering (1931).

For a detailed report of tests, with photographs, see the chapter "Rutot's Triangles" in Laboratory Investigations into Psychic Phenomena by Hereward Carrington (n.d.). It was not possible for Carrington to confirm the "instrumental communication with the dead" claimed by Rutot. Mechanical faults were not ruled out, and it was suggested that Rutot's claimed results may have been due to experimenters with mediumistic or tele-kinetic powers.

(See also electronic voice phenomenon )