140 FIELDS AND MKBUS : DELAWARK RIVER WATER. 



Easton, Pa. This was clearly shown several years ago (1900) 

 when there was a typhoid epidemic in Behndere, N. J. It 

 was only a few days later that cases appeared in Phillipsburg, 

 just opposite Easton, Pa., and the origin of the cases was 

 traced to the Delaware River. This proves conclusively that 

 the bacteria can travel this distance and thus be able to pro- 

 duce an epidemic. 



(3) The next and last consideration is that of the number 

 of bacteria in the water. There have been many attempts 

 made to set standards by which the sanitary quality of the 

 water would be fixed by the number of bacteria present. 

 Many of these have been unsatisfactory, but of late many 

 conservative sanitarians have agreed that a water having 

 " less than 100 bacteria per c. c. is unpolluted, one with 500 

 bacteria per c. c. or over as being open to suspicion, and one 

 over 1000 bacteria per c. c. as being contaminated by sewage." 



Another authority gives us the following: "If the water 

 contains over 500 bacteria per c. c. at 20° C, and over 50 

 bacteria per c. c. at 37° C, and shows B. coli in i c. c. 

 samples, it shall be condemned." 



As a result of careful consideration of all the factors con- 

 cerned, the authors come to the conclusion that the water of 

 the Delaware River at Easton, taken as a whole, without fil- 

 tration, is unfit for potable purposes. 



