QUALITATIVE BACTERIOLOGICAL ANALYSIS. 25,> 



Koch^s vibrio was introduced into these three waters, and the 



following results were obtained : 



These results showed that Koch's vibrio could not be detected 

 forty-eight hours after inoculation, although No. II. specimen 

 contained large quantities of nitrates, and No. III. specimen 

 contained a good deal of organic matter. In these experiments 

 special methods were not used to isolate the vibrios, so the 

 results must be accepted with considerable reservation. 



Nicati and Rietsch found cholera vibrios in 



Sterilised distilled water after 

 Marseilles canal-water after 

 Sea- water after 

 Harbour-water 

 Bilge- water . 



20 days. 



38 ,", 

 64 

 81 

 32 



De Giaxa found cholera vibrios in unsterilised sea-water after 

 two to four days ; in sterilised sea-water the vibrios appeared to 

 multiply, and he detected them after several weeks. Koch 

 found vibrios alive after thirty days existence in well-water ; 

 but in a canal-water at Berlin he only found them up to six or 

 seven days; and when the water was mixed with faeces, the vibrios 

 seemed to disappear after twenty-seven hours. Babes found 

 that cholera vibrios lived for seven days in Berlin tap- water. 

 Wolff hugel and Riedel stated that cholera spirilla did not mul- 

 tiply in sterilised water kept at 16 to 20 C. ; and in un- 

 sterilised water kept at the same temperature they found the 

 vibrios disappeared in a few days. Hueppe, working with 

 sterile distilled water containing common salt, found the spirilla 



