Many articles regarding the efficiency of silver arsphenamin have appeared in the literature since Kolle,1 in 1918, published the first of his series of reports. This much is established: it is an efficient spirocheticide; it is reasonably free from reactions, and it can be as conveniently administered as any other arsenical preparation.
The twenty-one cases reported were Wassermann fast. The patients, previous to the administration of the silver preparation, had had from four to thirty-four injections of arsphenamin and from thirteen to sixty-seven intramuscular injections of an insoluble mercury salt. The presence of a persistently positive Wassermann reaction in cases of intensive treatment is conceivably due to the continued activity of nests or foci of spirochetes resistant to medication. These foci are usually present in the cardiovascular and nervous systems. Detailed reexamination of these patients revealed evidence of activity that was unsuspected before treatment was instituted. These data are