214 GERMICIDES AND ANTISEPTICS. 



crepancies arise from the following circumstances : 

 (a) The different bacteria which have been used 

 as test-organisms differ within certain limits as 

 regards vital resistance to the action of germicide 

 agents. A like difference may occur in a particu- 

 lar species (b) as the result of the presence or 

 absence of reproductive spores ; (c) because of dif- 

 ferent conditions relating to the physical character 

 of the material containing the germs; e.g., solid 

 or fluid, coagulated masses, etc; (d) from a differ- 

 ence in the reaction of the media in which they 

 are contained ; (e) from a difference in the time of 

 exposure to the action of the reagent. 



The list which follows is arranged, for con- 

 venience, in alphabetical order. The writer has 

 given his own results the precedence ; and, as his 

 experiments were made -with special care by a 

 method which offers the greatest possible security 

 against error, he believes that they will be found, 

 in the main, to be trustworthy. The letter S, 

 enclosed in brackets, will be used to designate 

 these ; while results obtained from other sources 

 will be followed by the name of the experimenter 

 who has reported them. 



In the author's experiments, unless otherwise 

 stated in the text, the time of exposure to the 

 action of the germicide agent was two hours. The 

 septic micrococcus, frequently referred to below 

 as one of the test-organisms employed, is from 

 the blood of a rabbit recently dead, as the result 

 of inoculation with human saliva ; and, when 



