“The doctor was convinced, saying that it was contrary to reason, but he must believe. I then proposed that the doctor should mark; and directed Bishop to look in his mother’s house, in Lancaster, Pa., (where he had never been) for a clock; he said there was one, and told the time by it; one of the officers calculated the difference in time for the longitudes of Lancaster and Genoa, and the clock was found to agree within five minutes of the watch time.” Such clairvoyance is very rare; in fact, it is difficult, at first thought, to believe in its existence. Nor should its alleged possession be credited in any instance until all possibility of deception has been excluded. The example just related seems to be, in this respect, one of the best, for the reason of its occurrence in a little group of men whose isolation and thorough acquaintance with each other must have reduced the chances of simulation to the lowest degree. When carefully considered, moreover, it is apparent that the exaltation of the functions of sight and of hearing in this case was not different in kind or in degree from that that has already been recorded in connection with certain cases of natural somnambulism and of dreaming. The condition of the brain is probably identical in all such instances; it is the mode of its induction that is subject to variation. The remarkable feature of the hypnotic state consists in its production at the pleasure of either the subject or of the agent under whose control he has passed; whereas the phenomena of natural somnambulism and of the clairvoyant dream occur only during sleep, and independently of the will of the patient.