E & M ELECTRONIC & MECHANICAL

INSTRUMENTS CONNECTED BY INSTRUCTORS TO ANIMALS AND HUMANS IN LABORATORIES AND BY PHYSICIANS IN HOSPITALS AND PATIENTS' ROOMS, RESPECTIVELY, TO TEACH RECORDING AND TO RECORD BLOOD PRESSURE, ELECTROCARDIOGRAMS, RESPIRATION, ELECTROMYOGRAMS, ELECTROENCEPHALOGRAMS, PULSE CONTOURS, SKIN RESISTANCE, HEART RATES, HEART SOUNDS, TEMPERATURE, OXYGEN TENSION, FLUID DROPS AS IN GLAND SECRETION, NERVE AND MUSCLE CONDUCTION VELOCITIES AND OTHER RELATED PHYSIOLOGICAL EVENTS