ANTISEPTICS AND DISINFECTANTS. 153 



from twelve to sixteen grammes. The retarding 

 influence, however, of certain substances when 

 diluted, and the fact that disinfectants are some- 

 times equally efficacious in a diluted form when 

 their application is prolonged, seem to indicate 

 measures which may be adopted, in some cases, 

 with chances of success, such as the inhalation of 

 antiseptic vapours in phthisis. For the most part 

 the physician must look rather to combating the 

 effects of micro-organisms by restoring to its 

 normal standard the lowered vitality which enabled 

 the bacteria to get a footing. 



There is no wider field for research than the 

 determination of the real effect of disinfectants 

 and antiseptics. Painstaking and laborious as 

 the researches are which have been hitherto 

 made, the subject is so beset with fallacies, 

 leading, in some cases, to totally erroneous conclu- 

 sions, that it is not surprising that one meets on 

 all sides with conflicting statements. The author 

 has no intention of analysing these results, but a 

 general idea will be given of the methods which 

 have been employed, and for further details 

 reference must be made to the original papers 

 mentioned in the bibliography. 



Chemical substances. It was customary to judge 

 of the power of a disinfectant or antiseptic by 

 adding it to some putrescent liquid. A small por- 

 tion of the latter was, after a time, transferred to 

 some suitable nourishing medium, and the efficacy 



