“…Levaditi andVaisman (1946, 1950) and Kolmer andRule (1947, 1948) have shown in rabbit syphilis a synergistic effect from the association of penicillin and bismuth. We asked Dr. Cosar (Durel, Rayroux, Siboulet, and Daguet, 1949) to investigate the possible inhibiting action of bismuth upon penicillin in experimental pneumonia in mice, and no such action was noted.…”