60 ELEMENTS OF WATER BACTERIOLOGY 



may prove of great significance, as a few practical 

 examples may make clear (Winslow, 1901). 



In the spring of 1900 the city of Hartford, Conn., 

 was using a double supply, from the Connecticut River 

 and from a series of impounding reservoirs among the 

 hills. A single series of plates showed from 4000 to 

 7000 bacteria per c.c. in the water of the river, while 

 the reservoir water contained 300 to 900. The abandon- 

 ment of the river supply followed, and at once the 

 excessive amount of typhoid fever in the city was 

 curtailed. 



In the fall of 1900, Newport, R. I., experienced an 

 outbreak of typhoid fever, and when suspicion was 

 thrown upon the surface water-supply, chemical analysis 

 of the latter was not wholly reassuring; but there were 

 only 334 bacteria per c.c. in the water from the taps, 

 while a well in the infected district gave 6100. It was 

 no surprise to find, on a further study of the epidemic, 

 that the well was largely at fault and the public supply 

 was not. 



In the case of ground-water the evidence is usually 

 even more distinct. At Framingham, Mass., in 1903, 

 high chlorin content in the public supply, drawn from a 

 filter gallery beside a lake, had led to public anxiety. 

 Five samples from different parts of the system showed 

 averages of i, 2, 2, 2, and 4 bacteria per c.c; and 

 taking this in conjunction with the other features of 

 the bacteriological analysis, it was possible to report 

 that any pollution introduced upon the gathering 

 ground had at the time of examination been entirely 

 removed. 



