MODERN SLEEP-LEARNING: Page 109

specific mental picture, with cumulative and powerful effects. Devices employ two techniques: one utilizes a tape machine; the other employs a record player or phonograph. In the case of the latter, the record player should have all four speeds, 78, 45, 33/2 and 16 RPM—because the available records come in these different speeds. The record player must also be able to repeat the records over and over automatically; if it is the type record changer that automatically shuts itself off, the shut off lever must be taped down. Tape machines are preferred to record players. The magnetic tape equipment of today allows the student to record and play back his study material immediately on the same instrument. Tape allows the absolute minimum of undesirable noise. Whereas a record can become worn and scratchy, the tape has an unlimited noise-free life. Anything available on records is easily transferred to tape, and, since tape operates on a principle of organization and reorganization of magnetic particles on the tape ribbon, when there is no further need for the study material presently recorded, tape can be easily erased by recording over the original material. An endless tape cartridge of varying time lengths, depending on the study time of the material to be learned, allows continuous repetition of the material. These nocturnal messages are heard through a "pillow speaker" which rests under the pillow and, by controlling the volume, will repeat the message for your ears only. For those who toss in bed, or who are slightly hard of hearing, a speaker of the bone conduction type