16 MICRO-ORGANISMS AND FERMENTATION. 



absolutely no effect on the anthrax cells and spores. In the 

 form of vapour, carbolic acid acts more strongly, although 

 even two hours' action of its vapour at 75 C. proved unable 

 to destroy the vitality of these spores. Sulphurous acid is not 

 able to destroy all germs, even under very favourable con- 

 ditions. On the other hand, chlorine, bromine, and corrosive 

 sublimate are efficient disinfectants. According to Koch, 

 corrosive sublimate in the proportion of 1 in 1000 acts fatally 

 on all germs. According to experiments made by Johan-Olsen, 

 however, mould-fungi are only destroyed by more concentrated 

 solutions ; e.g., Penicillium glaucum only by a solution contain- 

 ing 1 in 400. Several bacteria, the organisms of puerperal fever, 

 abscesses, and putrefaction, likewise germinate and grow, 

 although more slowly than usual, on slices of potato saturated 

 with a solution of sublimate containing 1 part in 500, and 

 their growth is only checked by a concentration of 1 in 300. 

 Gruber found from recent investigations, carried out with all 

 precaution, that anthrax spores, for instance, were only killed 

 by 5 parts of sublimate in 1000, 1 part of sublimate hydro- 

 chloric acid in 1000, 1 part of sublimate tartaric acid in 

 1000. 



For cleansing pipes, coolers, etc., which often contain very 

 considerable deposits of organic matter liable to decomposition 

 through the agency of micro-organisms, a solution of soda is to 

 be recommended ; it acts by dissolving and loosening resinous 

 and albuminoid matters, which can then be removed by means 

 of water. Experiments made by Aubry and Will have proved 

 that chloride of lime, even when strongly diluted (2 5 per 

 cent, of chlorine) is a very efficient disinfectant, owing to its 

 deadly action on fungi. This substance being very cheap is 

 therefore specially suited for cleansing walls, pavements, 

 gutters, etc. Bisulphite of lime is also very efficient (used in 

 solutions containing 2 4 per cent, of sulphurous acid). The 

 filter-bags which, according to the investigations of Will, 

 often contain very considerable accumulations of wild yeasts 

 and bacteria in the very texture of the material, and which 



