Theoretically, then, we find that the most perfect condition either for the conveyance or the reception of telepathic impressions or communications is that of natural sleep. The only question that remains to be settled is whether it is possible for the agent or operator so to control his own subjective mind during his bodily sleep as to compel or induce it to convey the desired message to the sub-consciousness of the patient. To settle this question, we must again have recourse to the record of the labors and researches of the London Society for Psychical Research. It might well be inferred that this power must necessarily be possessed, when we take into consideration the general law of suggestion, coupled with the fact that the subjective mind is perfectly amenable to control by auto-suggestion. If the law of suggestion is valid and universal, the conclusion is irresistible that this power is inherent in man, even without one experimental fact to sustain it. Fortunately, we are not left to conjecture in regard to this important question. The literature of psychical experiment is full of facts which are demonstrative. Some of the experiments recorded in "Phantasms of the Living" show that a vastly greater power exists in this direction than would be required to convey a simple therapeutic suggestion to a sleeping patient. The following experiments are recorded in "Phantasms of the Living."[33] In the first case, the Rev. W. Stainton Moses was the percipient, and he corroborates the following account, written by the agent:-- "One evening I resolved to appear to Z at some miles' distance. I did not inform him beforehand of the intended experiment, but retired to rest shortly before midnight with thoughts intently fixed on Z, with whose room and surroundings I was quite unacquainted. I soon fell asleep, and awoke next morning unconscious of anything having taken place. On seeing Z, a few days afterwards, I inquired, 'Did anything happen at your rooms on Saturday night?' 'Yes,' replied he, 'a great deal happened. I had been sitting over the fire with M, smoking and chatting. About 12.30 he rose to leave, and I let him out myself. I returned to the fire to finish my pipe, when I saw you sitting in the chair just vacated by him. I looked intently at you, and then took up a newspaper to assure myself I was not dreaming; but on laying it down I saw you still there. While I gazed, without speaking, you faded away.'" The next case was recorded by the agent, Mr. S.H.B., at the time of the occurrence, and his account of it is duly verified by the percipients. It is as follows:--