Dr. Puharich, an able student of the phenomena of extra-sensory perception, investigated the properties of the mushroom in an earlier book, The Sacred Mushroom. Now he has gone a step further, and correlates the facts of ESP, precognition and the alleged ability of the personality to free itself from the physical body, with the latest findings of modern physics, chemistry, biology, medicine and neurology. The first seven chapters describing now fairly familiar ESP subjects are relatively simple reading. Chapters 8 and 9 deal respectively with the methods of the Siberian Shaman and the Tibetan Yogi to free the personality from the body in what calls ""the ritual of the irrational"". In later chapters he tries to explain these strange mental states in terms of modern medical and physical discoveries. These chapters are very difficult reading and can only be evaluated by scientists trained in these fields. The book contains, in an appendix, a complete account of the tests made on the sensitize, Mrs. Elleen Garrett, in a Faraday copper to determine the connections between ESP and electromagnetism. This material has been long awaited in the ESP field in spite of a sometimes subtle frivolity in Puharich's approach, and on occasion a haphazard organization of his very complex material (which may throw some doubt on his scientific thoroughness), this will have a definite appeal in certain among researchers and the readers for whom this subject has always held a certain fascination.