38 



METHOD OF DESTROYING ALG^E IN- WATER SUPPLIES. 



Effect upon Bacillus coli of exposure to colloidal solution of copper at room temperature. 



[Determination made in tubes of bouillon, -f indicates growth after 48 hours' inoculation; indicates 



no growth.] 



a Experiment conducted in test tubes containing 10 cc. each of sterilized water. The copper foil was 

 sterilized and added immediately before inoculating the tubes with the usual 3 mm. loop of a 24-hour 

 culture of B. coli. 



Effect upon Bacillus coli of exposure to colloidal solution of copper at room temperature. a 

 [Determination made in Petri dishes.] 



a Experiment conducted in test tubes, each containing 5 cc. of sterilized water. The copper foil 

 was sterilized and added immediately before inoculating the tubes with the usual 3-mm. loop of a 

 24-hour culture of B. coli. 



Effect upon par acolon of exposure to collodial solution of copper at room temperature. a 



[Determination made in tubes of bouillon. + indicates growth after 48 hours' inoculation; indi- 

 cates no growth.] 



a Experiment conducted in test tubes containing 10 cc. each of sterilized water. The copper foil was 

 sterilized and added immediately before inoculating the tubes with the usual 3mm. loop of a 24-hour 

 culture ot paracolon. This experiment was duplicated upon another form of paracolon with exactly 

 the same results. - 



