For the same way, if we were dealing with telepathy, it is to be supposed that the communicators would be the persons whom the sitters expect. Now this is far from being the case. In the fifteen years during which Mrs Piper's mediumship has been studied, a great number of communicators have appeared about whom nobody was thinking. Professor Hyslop, among others, says that he has met with several communicators whom he did not in the least expect. Others whom he expected did not appear. It is a fact worthy of remark that in Professor Hyslop's sittings only those persons appeared who were capable of telling something of a nature to prove their identity; the others seem to have been systematically put aside by Imperator, even when information concerning them was abundant in the consciousness and subconsciousness of the sitter. It would seem that, if we were dealing with telepathy, the self-styled communicators would most easily utter the least remote ideas of the sitters' minds; the nearest, most vivid ideas ought to appear first. Now this is far from being the case. It seems to make no difference to the communicator whether the idea is familiar or otherwise to the minds of the living. When it is a question of facts entirely unknown to the sitters and known only to persons living at a great distance, this distance might be expected to affect telepathic mind-reading; nothing in nature authorises us to neglect this law of distance. We can only conceive the telepathic process as a propulsion of waves through space; these waves should decrease with distance; the contrary is absolutely inconceivable. Now this does not happen; if the fact exists only in the consciousness of a person who is at the time at the far ends of the earth, it makes no difference in the precision of the details. If an analogy should be made between telepathy--as we must conceive it, to explain the phenomena--and wireless telegraphy, Mrs Piper entranced must be regarded as a mere coherer of the telepathic waves. But this analogy is non-existent; wireless telegraphy is far from being unaffected by distance, and besides, when the coherer functions, it is because another instrument is emitting particular waves. When a fact known only to a distant person is reported, as in Mrs Piper's phenomena, it rarely happens that the distant person was actively thinking of the fact, which was lying unnoticed in the lowest strata of his consciousness. When the experimenter makes his inquiries at the conclusion of the sitting, it is often found that a definite effort on the part of the absent person is required before the fact is recalled to memory. It would be well to reflect before we grant to telepathy a power of omniscience, independent of all known laws.