Since October, 1934, we have treated 40 cases of psychoses by somnifaine narcosis in the Glasgow Royal Mental Hospital. The technique employed by us was that recommended by Ström-Olsen. The patients were isolated in a quiet room, in partial darkness, and a nurse was constantly in attendance by night and day. As a preliminary to the treatment, insulin and glucose were given for a few days beforehand, while the patient received daily bowel wash-outs. The amount of glucose given was 1 oz. to 1½ oz. three times a day, along with 10 units of insulin. This insulin and glucose routine was continued during the treatment, and for some days after the administration of the somnifaine was discontinued. The somnifaine was injected intra-muscularly in 2-c.c. doses. The degree of narcosis one wished to produce was that approximating as nearly as possible to natural sleep. Throughout, one tried to keep the patient in such a state that they were able to be roused from time to time for feeding. The amount of somnifaine necessary to produce this state varied with each patient, but as a rule we found that 6 c.c. of somnifaine given in 2-c.c. doses in the 24 hours was the average amount required. The treatment was continued for 10 to 14 days.