It has already been noticed that persons in the hypnotic state seem to have certain of their senses greatly heightened in power. They can remember, see and hear things that ordinary persons would be entirely ignorant of. There is abundant evidence that a supersensory perception is also developed, entirely beyond the most highly developed condition of the ordinary senses, such as being able to tell clearly what some other person is doing at a great distance. In view of the discovery of the X or Roentgen ray, the ability to see through a stone wall does not seem so strange as it did before that discovery. It is on power of supersensory, or extra-sensory perception that what is known as telepathy and clairvoyance are based. That such things really exist, and are not wholly a matter of superstition has been thoroughly demonstrated in a scientific way by the British Society for Psychical Research, and kindred societies in various parts of the world. Strictly speaking, such phenomena as these are not a part of hypnotism, but our study of hypnotism will enable us to understand them to some extent, and the investigation of them is a natural corollary to the study of hypnotism, for the reason that it has been found that these extraordinary powers are often possessed by persons under hypnotic influence. Until the discovery of hypnotism there was little to go on in conducting a scientific investigation, because clairvoyance could not be produced by any artificial means, and so could not be studied under proper restrictive conditions. We will first quote two experiments performed by Dr. Cocke which the writer heard him describe with his own lips. The first case was that of a girl suffering from hysterical tremor. The doctor had hypnotized her for the cure of it, and accidentally stumbled on an example of thought transference. She complained on one occasion of a taste of spice in her mouth. As the doctor had been chewing some spice, he at once guessed that this might be telepathy. Nothing was said at the time, but the next time the girl was hypnotized, the doctor put a quinine tablet in his mouth. The girl at once asked for water, and said she had a very bitter taste in her mouth. The water was given her, and the doctor went behind a screen, where he put cayenne pepper in his mouth, severely burning himself. No one but the doctor knew of the experiment at the time. The girl immediately cried and became so hysterical that she had to be awakened. The burning in her mouth disappeared as soon as she came out of the hypnotic state, but the doctor continued to suffer. Nearly three hundred similar experiments with thirty-six different subjects were tried by Dr. Cocke, and of these sixty-nine were entirely successful. The others were doubtful or complete failures.