Researches in the phenomena of spiritualism (1874)
Crookes, William, 1832-1919 · London : J. Burns · leaf 38
it, is a on Psychic Force. 35 grooved frame carrying a flat box similar to the dark box ofa photographic camera. This box is made to travel by-clock-work horizontally in front of the moving index, andit contains a sheet of plate-glass which has been smokedover a flame. The projecting steel point… … VylV^U end B of the board, the result is a vertical line, whoselength depends on the weight applied. If, whilst the clockdraws the plate along, the weight of the board (or the ten-sion on the balance) varies, the result is a curved line, fromwhich the tension in grains at any moment during the…
Spiritualism · Parapsychology
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