The combined internal and external use of tinct. ferri perchloridi is advised by Ricord (Medical Times, i., 1859). Roget adduced instances of it curing chancre when applied early, and he maintained that the local use of an acid solution directly after exposure would prevent gonorrhoeal, and even syphilitic contagion ("Traite sur le Perchlorure de Fer," 1860, Paris). Rabuteau speaks favorably of the remedy - substituting only citric acid for the more irritant hydrochloric. He adopts the following formula - R. Tinct. ferri perchloridi (30° Beaume, = 0.879 sp. gr.), 12 grammes; acidi citrici, 4 grammes; aquae, 24 grammes: solve f. lotio.