It appears that the patient led a normal life and had had six children, the last of whom was born about four months before her coming to the hospital. The first symptoms appeared about a month after the birth of the child, when, one afternoon, Mrs. Rivers suddenly fell unconscious while ironing. She remained unconscious for nearly three hours. During this attack there were no convulsive movements or tongue-biting; and after the spell, she felt neither lame nor sore, but merely tired. This was Mrs. Rivers’ statement; but her daughter stated that the patient really did have convulsive movements. A week later came a second convulsion, followed by daze and stupor. This second attack lasted two hours. About a week before entrance, the patient had remained in bed on account of dull grinding pain in the left side of the head, below the ear, and upon this day the patient vomited twice. In addition to the dull grinding pain, there were pains referred to the ear itself and to the left side of the head, especially over the left eye; there were no pains on the right side of the head. The next day the patient was better, but the day thereafter again remained in bed. The only other symptoms were cold feelings at times and bright spots in the field of vision. No =mental symptoms= were observed in Mrs. Rivers except a bit of depression after her hasty retreat from the hospital the first time. Upon her second admission, however, after a week or ten days’ residence, apathy developed together with considerable amnesia for the same facts she had quite readily remembered a few days previously. Along with the apathy and amnesia developed considerable headache; and there were attacks of vomiting. =UNTOWARD SYMPTOMS OF THERAPEUTIC AGENTS= =A. SALVARSAN= CYANOSIS MALAISE RAPID PULSE PERSPIRATION RESPIRATORY DIFFICULTIES FEVER NAUSEA, VOMITING, DIARRHOEA DERMATOSES EDEMA KIDNEY IRRITATION LIVER IRRITATION INTENSIFICATION OF SYMPTOMS COLLAPSE =B. MERCURY= SALIVATION FETID BREATH EXCESS FLOW OF SALIVA TENDERNESS OF TEETH—LOOSENING AND FALLING OUT SPONGY GUMS—EROSION METALLIC TASTE NECROSIS OF BONES OF JAW SORENESS OF PARETIC AND MAXILLARY GLANDS SWELLING AND EROSION OF TONGUE AND MUCOUS MEMBRANES GASTRO-INTESTINAL SYMPTOMS ANEMIA PAIN IN JOINTS NEPHRITIS =C. IODINE=