A result is classed as positive if the magnitude of the string vibrations during imagination clearly and considerably exceeds that during relaxation. In the experiment of imagining the lifting of a 10-pound weight (120 tests on 11 subjects, 8 trained, 3 untrained), the results were positive in 93% of the tests. In imagination of various acts performed with the right arm (4 subjects) results were positive for action-potentials from the right biceps-brach-ial region in 97.5% (159 out of 163) of the tests. In recollection of various muscular acts commonly performed with the right arm (9 subjects, 8 trained to relax, 1 untrained), for 7 out of 9 subjects, the results predominantly showed action potentials from the biceps-brachial region (in 60 out of 90 tests). In 2 of the 9 subjects, lengthened string vibrations occurred during recollection in only 12 of 54 tests. The action-potentials that are here found characteristic of imagination and recollection of muscular acts are readily distinguished from the psychogalvanic reflex because of marked differences in voltage, reaction-time, frequency per sec., wave-form, direction of potential, tissue of origin, and stimulus. Relaxation of the neuromuscular processes characteristic of the occurrence of voluntary conscious activities such as imagination of lifting a 10-pound weight is accomplished within 0.3 to 0.4 sec. on the average in the present experiments. It is confirmed that diminution of conscious activities can be brought about by muscular relaxation (Jacobson, 1925, 1929, 1930).