Note 146 — Chapter XV

It should perhaps be said that there is nothing in the experience of the many persons who have so far tried crystal gazing, at the instance of the S.P.R., to indicate risk of injury to health. It is no doubt not advisable for an invalid, or for any one suffering from headache, or undue fatigue, to try the experiment. Indeed, the experience of Mrs. Verrall and others is that success under such conditions is unattainable. But with ordinary care to avoid straining the eyes, no evil effect, it is thought, need be apprehended; and there is probably no form of experiment which at the cost of so little trouble may be expected to yield results of so great interest and value. There is of course no magic in the crystal; a glass paper-weight, a mirror, or a glass of water will serve the purpose equally well. Records of experiments will be welcomed by Mr. F. W. H. Myers, from whose suggestive article many of the illustrations quoted in the text are taken. (See Proc., vol. viii., p. 436, etc.)