1. What are the causes of hemiplegia and confusion or unconsciousness? We must consider epilepsy, brain tumor, cerebral thrombosis, cerebral hemorrhage, multiple sclerosis, cerebral spinal syphilis, and general paresis. =MILD TREATMENT, often thought “adequate,” MAY FAIL, WHEN INTENSIVE TREATMENT PROVES SUCCESSFUL.= =Case 121.= Arthur Bright, a printer, had acquired syphilis in his 49th year, some six months before examination. He had been treated during these six months by three injections of salvarsan, injections of mercury, and mercury by mouth. He had been apparently cured until about a month before admission. He had fallen without warning from his chair in a convulsion accompanied by unconsciousness, which lasted about two hours. The patient had since been feeling rather peculiar. For instance, time seemed to flow too rapidly. Sometimes the patient had had difficulty in talking. =Physically=, nothing abnormal could be found either in general condition or =neurologically=. The patient was, however, incontinent. =Mentally=, he was apathetic and unalert, even paying no attention to his outside physician when he came to visit him. The =diagnosis= of cerebrospinal syphilis already suggested by his history was confirmed by the laboratory tests, which showed a positive serum and spinal fluid W. R., paretic gold sol reaction, 41 cells per cmm., an excess of albumin, and a positive globulin test. 1. What is the prognosis in cerebrospinal syphilis in the early secondary stage? The prognosis appears very good provided that intensive treatment be given and provided that no vascular insult or other focal destructive lesion occurs before treatment has had time to do its work. 2. Why did not the “effective” (?) treatment for the syphilis, dating from the primary lesion, succeed in staving off the cerebrospinal syphilis? It remains a question whether the treatment by three injections of salvarsan was efficient in this particular case. Of course, it may prove true that no treatment whatever in the present stage of knowledge will stave off cerebrospinal symptoms in certain cases. =Treatment=: Bright was given intravenous injections of diarsenol twice a week, with occasional injections of mercury salicylate. After two weeks, the patient seemed markedly improved, and continued to improve rapidly. He was symptomatically well at six weeks. The spinal fluid had then become negative, although the serum W. R. had remained positive. After discharge from the hospital, Bright returned to his work, but continued to take the diarsenol treatment weekly, and two months later the serum W. R. became negative.