An instrument said to have been constructed under spirit
guidance by the Dutch physicists Dr. J. L. W. P. Matla and Dr.
G. J. Zaalberg Van Zelst of The Hague to obtain direct communication
with the spirit world without using a medium. The device
consisted of a cylinder into which the spirit influence was
supposed to enter, a table isolated by a sheet of glass and
charged with an electric current, a pair of scales, and a writing
apparatus arranged on the Morse system. Enclosed in a room,
the action of the instrument was observed through a small glass
window. Long communications were allegedly spelled out by
spiritual intelligences using a lettered dial at the top of the machine.
The result of these investigations was detailed by the inventors
in their work Het Geheim van den Dood (5 vols., ca. 1911).
A one-volume version was issued in French under the title La
Solution du Mystère de la Mort (1930). A report of the Dutch Physical
Society objected that no sufficient allowance was made for
possible earth tremors and other normal causes. Nevertheless,
such objections do not give satisfactory explanation for the curious
communications received from the deceased father of
Zaalberg Van Zelst.
For a discussion of the work and apparatus of Matla and Van
Zelst, see Hereward Carrington, Laboratory Investigations into
Psychic Phenomena (1939). (See also Ashkir-Jobson Trianion;
Communigraph; Reflectograph)