290 PURIFICATIOlSr OF PUBLIC WATER SUPPLIES. 



bacteriological examinations made daily, as have the 

 Germans. The first reliable examinations of this kind 

 were made by Prof. Drown, of Boston, in November, 

 1891. The samples were collected by myself in sterilized 

 bottles, which were placed, each, in an air-tight metallic 

 case, and these in a tin pail with sufficient ice to keep 

 cool without freezing. In freezing weather no ice was 

 used. They were, except the first, collected in the after- 

 noon and forwarded by express, so that they were 

 received by Prof. Drown early the next morning. 

 The results were as follows : 



Bacteria per Cubic Centimeter. Per Cent. 



The past year we have made a decided advance, and 

 since April 17th ten examinations were made. These 

 were made by D. B. Ward, M. D., the President of this 

 section. The samples were collected in sterilized bottles, 

 and taken to Dr. Ward generally within an hour of 

 collection. 



The dates and results are as follows : 



Date. Bacteria per Cubic Centimeter. Per Cent. 



22S 



