Hypnotism, Chicago, 1958. 'Model Blanche Kos sits in front of a new do-it-yourself hypnosis machine called a brainwave synchroniser. The machine induces a state of trance or deep relaxation in susceptible individuals by blinking a light. According to its inventor, Sidney A Schneider of Skokie in Illinois, it will hypnotise at least 50 percent of all persons who watch the flickering light for between two and five minutes, and will give others a feeling of tranquillity'.
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