

OF TJ 







V. 8 3 



THE VITAL PHENOMENA OF BACTERIA 



cate that the property of inhibition and that of 

 disinfection do not always run parallel, just as 

 might be expected from the fact that direct cor- 

 rosive effects differ from phenomena that take 

 place in blood and tissue j uices. Poisonousness 

 is, therefore, only relative. From this point of 

 view the cresols are to be regarded as from 

 two to four times as strongly disinfectant 

 towards some bacteria as carbolic acid, or from 

 two to four times less poisonous than carbolic 

 acid. That is to say, from one-half to one- 

 fourth part of cresol possesses as great disin- 

 fecting power as one part of phenol. Since 

 both bodies are equally poisonous, it is best to 

 use the smaller amount of cresol and thus to 

 minimize the danger from poisoning. Again, 

 the very powerful disinfectant iodine tri-chlo- 

 ride is, according to Behring, relatively harm- 

 less, since at the beginning of the disinfecting 

 process sodium iodide and sodium chloride are 

 formed. As early as 1886 it was discovered 

 also that the ortho-phenol-sulfonic acids have 

 just as strong disinfecting power as the phenols ; 

 they corrode less and are not so poisonous. 



These effects are in the line of specific dis- 

 infection, that is the disinfectant acts more 

 injuriously upon the bacteria than upon the 

 cells of the human body. It is perhaps to be 

 remarked as an advance in the same direction 



