between the hallucination and the stimulus which has generated it. It is frequently very close, any change in the stimulus either destroying the hallucination or making in it a corresponding change. In the case of crystal gazing, for example, if one looks at the image through a magnifying glass or prism, it is sometimes destroyed and sometimes magnified or doubled. Very often hallucinations originated independently appear to attach themselves in much the same way to some contiguous percept and become practically a part of it. The element to which it is attached is what the French investigators have termed the point de repère, and M. Binet has endeavored to show that without such a point de repère no hallucination can exist. The matter is still under discussion, and must be set aside with this brief allusion.
If we once admit that subconscious states exist, we are tempted in many cases of hallucination to make use of the conception to explain the facts. In the case of Mrs. Beasant's ghost, for example, it may be that the memory was revived before the apparition was seen, but remained subconscious until externalized by some obscure agencies which one can not precisely specify. An analogous experience—in this case a crystal vision—is given by Miss X[1]
:"I find in my notebook a memorandum of August 3d as to a vision of a corner of a room, with a red carpet and walls decorated in stripes of pink, white, and green, for which for many months I was unable to account. Only a few days ago (May 10, 1889, is the date of writing) I called on a friend whom I had not visited since July, and whose house had, I observed, been newly and handsomely decorated. A letter which she had written to me before leaving town in the summer was by chance referred to, and on returning home I sought it, to settle a disputed point, and found that it was dated August 2d and contained the information that her staircase had been painted and 'looked at present like a Neapolitan ice.' This, I doubt not, supplied the coloring of my picture."
Here the development of the vision was influenced by an allusion contained in a letter read the preceding day which was no longer in mind. Now, one must suppose either that that allusion still existed in some way and was capable of influencing the vision, or that the vision had been suggested subconsciously, had existed subconsciously, and had been brought to light by the crystal, or that it had been suggested by the letter, forgotten, and then revived. Of these three suppositions the last is the most plausible, but it is difficult in other cases to resort to it. Take another case of Miss X
's: "On March 9th I saw in the crystal- ↑ Proceedings of the Society for Psychical Research, vol. v, p. 512.