Originally published in 1899, this account of recent investigations regarding hypnotism, automatism, dreams, phantasms, and related phenomena is accurate enough for scientists and simple enough for lovers of "ghost stories." On a thread of theory and discussion Dr. Mason links many startling examples from his own professional experience and from The Proceedings of the Society for Psychical Research. He includes a copy of a portrait made while in a trance by a person who had never painted before. R. Osgood Mason, M.D., was a Fellow of the New York Academy of Medicine.

Boston Transcript: "He repudiates the idea of the supernatural altogether, and in this he is in accord with the best thought of the day.Interesting and logical." Hartford Courant: "The work of a scientist and not of a crank.Fascinating reading." New York Times: "The curious matter he treats about, he presents in an interesting manner." Nation: "A popularly written book . A not inconsiderable contribution to psychical research." Chicago Tribune: "Certain to attract wide attention .

Thoroughly interesting . The spirit of his work is such as to deserve respectful attention from every scientific mind.".