42 ELEMENTS OF WATER BACTERIOLOGY. 



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 bac- 

 teria per c.c. in the water of the river, while the reservoir 

 water contained 300 to 900. The abandonment 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. L, experienced an out- 

 break of typhoid fever, and when suspicion was thrown 

 upon the public 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 not at all. 



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 aver- 

 ages of i, 2, 2, 2, and 4 bacteria per c.c.; and taking this 

 in conjunction with the other features of the bacterio- 

 logical analysis, it was possible to report that any pollution 

 introduced upon the gathering ground had at the time of 

 analysis been entirely removed. In such a case the bac- 

 teriological methods give a certainty attainable by no 

 other sanitary process. 



