720 GENEEAL THERAPEUTIC MEASURES 



powerful agency for disinfection at our command. Dry 

 heat, to be efficacious, must be applied at a' tem perature of 

 140° C. (284° F.) for three hours to' kill all bacteria aud 

 spores ; but this degree of heat scorches most fabrics and 

 destroys many materials. Boiling water quickly kills all 

 non-spore-bearing pathogenic bacteria, and these include 

 most of the organisms causing the common contagious and 

 infectious diseases (tuberculosis and anthrax excepted). 

 Two hours of continuous boiling will not destroy the most 

 resistant of micro-organisms — the spores of the hay ba- 

 cillus — but moist or saturated steam, at 230° F., will infallibly 

 kill any spores whatsoever within a few minutes. Fire is 

 the most complete disinfectant, because it not only destroys 

 germs, but their food and products. Water, like air, dilutes 

 germs and aids oxidation and destruction of organic matter ; 

 but, again like air, drinking water may be the source of in- 

 fection when sufficiently contaminated. 



MECHANICAL MEANS OF PEOCURING ASEPSIS. 



The placing of sole reliance upon chemical agents for 

 surgical antisepsis, in relation to the body, is a common 

 error. These agents may damage denuded tissue, and. do not 

 reach the micro-organism buried in the tissues. Therefore, 

 it is impossible to render infected, living tissue absolutely 

 aseptic, or sterile, by merely bathing it with chemical solu- 

 tions. Far more efficacious is mechanical cleansing of the 

 skin with soap, water and the scrubbing brush, and even of 

 infected raw surfaces with gauze and corrosive sublimate 

 solution,* supplemented, if necessary, by the knife, caustic 

 and drainage, to remove necrosed tissue and septic material. 



CHEMICAL AGENTS. 



Mercuric bichloride, carbolic acid, quicklime, chlori- 

 nated lime, sulphurous acirl, and chlorine, are more fre- 

 quently employed as disinfectants. Corrosive sublimate 



* Harrington's solution, see p. 216. 



Digitized by Microsoft® 



