M.B., 22, had suffered from trench feet in January, 1916, for which he had been in hospital for six months. He applied for treatment last summer on account of pain in his feet describing his condition as if he were “walking on hot plates.” The pain would generally last for half an hour to four hours, though occasionally it might be present for a whole day. After a few séances of percussion of the seventh cervical spine, complete freedom from discomfort ensued.