34 BACTERIOLOGY FOE NURSES 



arrest further multiplication. The chemical prod- 

 ucts of the various species may be favorable or in- 

 jurious to each other. 



Chemical Antiseptics and Disinfectants. — An anti- 

 se ptic retards theg nowth but does not k illb acteria . and 

 a dis infectant, or germicide, destrovs tl ]p nrggjiisTng^ 



By sterilization is meant the complete destruction 

 of , all bacteria, and all processes^ which sterilize 

 necessarily disinfect, but all disinfecting processes 

 do not sterilize, the difference being that in steriliza- 

 tion the spores ^re also destroyed. 



An enormous number of proprietary disinfectants 

 are constantly advocated for many purposes, but 

 complete disinfection may be obtained from simple 

 chemical compounds at a very slight comparative 

 expense, whereas the composition, strength, and 

 effectiveness of patented mixtures are unknown and 

 consequently unreliable, while the expense is great. 



^Lme_is__oneof^theoldest_^i^^ 

 mixed with water to the consistency of cream, it 

 is an excellent disinfectant for excreta and privy 

 vaults. By the addition of more water it is known 

 as whitewash, and is the best practical disinfectant 

 for cellars or rough walls of any kind, in houses, 

 barracks, stables, and other outbuildings. 



' Sterilization by steam, etc., is spoken of elsewhere. 



