A BACTERIOLOGICAL EXAMINATION OF THE 

 DELAWARE RIVER WATER. 



BY HOWARD WALKER FIKLDS AND PKRCV KLWOOD MKBUS. ''' 



In interpreting the results of bacteriological examinations 

 as regards the purity of the Delaware River at Easton consid- 

 erable difficulty is experienced. 



In a case of gross pollution, such as is seen by examining 

 the results of the Martin's Creek samples at Bangor and at 

 Martin's Creek, there is no difficulty. We know that the 

 creek is highly polluted at both places, and hence the water 

 can safely be condemned. The same can be said of the 

 Pequest Creek at Belvidere. But with the water of the Dela- 

 ware River at Easton, Pa., it is a different and more difficult 

 problem. The water is not highly polluted, neither is it in 

 good sanitary condition. 



In judging whether the water of the Delaware River is 

 safe or not several factors are involved : — 



(i) Self purification of the stream. 



(2) Longevity of pathogenic bacteria. 



(3) Number of bacteria in the water. 



(i) Under self purification there are five heads to be con- 

 sidered. They are, dilution, sedimentation, sunlight, aera- 

 tion and oxidation and antagonism to the bacteria. 



First, we note the effect of dilution. The two creeks 

 mentioned above are considerably smaller than the Delaware 

 River, and hence all the highly polluted water from these 

 creeks is diluted. This is not a purification, but a sort of 

 means of minimizing the danger, without removing it. 



Next may i)e mentioned sedimentation. In the ri\er there 



■■■■ Abstract from thesis, Ivat'ayette College, Easton, I'a., 1909. Tliroiitili 

 the kindness of one of the authors, Mr. Fields, a resident of Media, the 

 Institute is enabled to pul)lish this abstract. It is of especial interest a-^ 

 showing the factors to be considered m the exauiinatioii of ]nib]ic 

 water sui)])lie-. 



