BACTERIA, DESTRUCTIVE INFLUENCES 39 



poisonous and sensitive to albuminoids. Moreover, 

 these emulsions have the disadvantage of being opaque. 

 Lysol is mainly a solution of the cresols in fat or linseed 

 oil saponified with addition of alkali. It gives a clear 

 solution with water, having marked germicidal powers 

 and considerable solvency for grease. It is extensively 

 used in the form of a 1 per cent, solution in gynecologic 

 and obstetric practice. Tricresol, a refined mixture of the 

 three cresols, is soluble in water to the extent of 2.5 per 

 cent. It is about three times the strength of carbolic 

 acid. 



Quicklime, used in the form of freshly slaked lime 

 suspended in water, is a powerful disinfectant. A 1 per 

 cent, watery solution of the freshly slaked lime kills 

 bacteria which are not in the spore form within a few 

 hours. A 3 per cent, solution kills typhoid bacilli in one 

 hour, while a 20 per cent, solution, added to equal parts 

 of feces or other filth and thoroughly mixed, will com- 

 pletely sterilize them within one hour. 



Chlorid of lime, so called (really chlorinated lime), 

 depends for its efficacy on the chlorin it contains, and, 

 as this is readily lost on exposure to the air, it is im- 

 portant that chlorid of lime be kept in tight containers. 

 A solution in water containing 0.5 to 1 per cent, of 

 chlorid of lime will kill most bacteria in one to five 

 minutes. A 5 per cent, solution usually destroys spores 

 within one hour. Chlorid of lime is particularly useful 

 in the disinfection of stools. Together with washing-soda 

 it is also extensively used as a hand disinfectant by 

 surgeons. 



In recent years chlorinated lime is used extensively 

 in disinfecting municipal water-supplies. When so used 



