206 ACTION OF COAL-TAR PRODUCTS, 
Alpha-naphthol and beta-naphthol have about the same antiseptic and 
germicidal value. In the proportion of 1: 16,000 both prevent the develop- 
ment of the cholera spirillum in peptonized beef-tea, while 1 : 24,000 fails to 
prevent development. In the proportion of 1 : 3,000 both destroy the vital- 
ity of the cholera spirillum in bouillon cultures, twenty-four hours old, 
after two hours’ contact, while 1: 4,000 fails to destroy this microdrganism 
in the time mentioned—two hours. 
In experiments made with a solution of 1:1,000, added to an equal 
quantity of a twenty-four hours old bouillon culture—making 1 : 2,000 after 
mixture—and in which the time of contact varied from five to thirty minutes, 
alpha-, beta-, and hydronaphthol were found to destroy the cholera germ by 
fifteen minutes’ exposure, but to fail after ten minutes’ contact, so that the 
germicidal value of each of these is similar, or nearly so. : 
In all these experiments the line was sharply drawn between success and 
failure. No development occurred and the bouillon remained transparent 
in those experiments in which the germicidal action was complete, and a 
characteristic development occurred within twenty-four hours in those ex- 
periments in which there was a failure to destroy the spirillum. 
Benzo-naphthol has no germicidal power, probably because it is insoluble 
in water. At least this is my inference from the experiments made. One 
gamme was added to one thousand cubic centimetres of distilled water, and 
after vigorous shaking was placed in the steam sterilizer for half an hour. 
At the end of this time the greater portion, at least, of the benzo-naphthol re- 
mained undissolved at the bottom of the flask. The saturated solution (?) 
was then filtered and added to recent bouillon cultures of the cholera spiril- 
lum in the proportion of 1:1, 1: 2,1:4,and 2:1. At the end of two hours 
sterile bouillon in test tubes was inoculated from each of these and placed in 
the incubating oven. At the end of forty-eight hours a characteristic devel- 
opment of the cholera spirillum had occurred in all of the tubes. 
Olive Ovl.—Anthrax spores germinate after having been im- 
mersed for ninety days in pure olive oil (Koch). 
Owl of Mustard.—Koch found that the development of anthrax 
spores is prevented by 1:33,000. 
Owl of Peppermint.—A five-per-cent solution in alcohol failed in 
twelve days to destroy anthrax spores, but the development of these 
spores is restrained by 1: 33,000 (Koch). 
Oul of Turpentine destroys anthrax spores in five days, but failed 
to do so in one day (Koch). The development of anthrax spores is 
prevented by 1: 75,000 (Koch). The addition of 1: 200 to nutrient 
gelatin prevents the development of bacteria (Riedlin). An excess 
of oil of turpentine added to a liquefied gelatin culture of Staphylo- 
coccus aureus does not destroy this micrococcus in five hours (v. 
Christmas-Dirckinck-Holmfeld). 
Saprol.—Laser (1892) recommends this agent for the disinfection 
of the excreta of cholera and typhoid patients. He reports that in the 
proportion of 1: 100 it sterilizes liquid feeces in twenty-four hours. 
Skatol in excess in water has no germicidal power, as tested upon 
anthrax spores (Koch). 
Smoke.—The researches of Beu show that meats which have been 
preserved by smoking commonly contain living bacteria capable of 
growing in culture media; and Petri has shown that pork which has 
