12 C. M. BROOMALL : THE LOCAL \VA'rp:R SUPPLY. 



of September 17, 1904, and March 11, 1905, give valuable 

 data. In the latter two analyses there is shown an increase of 

 free ammonia. This may be due to the fact that the analyses 

 are not actually of identical portions of the water, since the 

 samples, being drawn at the same time both outside and inside 

 the filter, differ in age by the time required for the water to 

 pass through the settling basin and filter. Or, the increase of 

 free ammonia may be due to the fact that an actual decompo- 

 sition of organic matter had taken place in passing through 

 the filter. 



The analyses of May 27, 1905, give a comparison of the 

 raw waters of Ridley and Crum Creeks. This shows Ciiim 

 Creek slightly the better, although the analyses of the filtered 

 waters, November 8, 1904, shows the Media water a trifle 

 better. If this were the permanent state of affairs, it would 

 indicate that the Media filtration plant was acting more effici- 

 ently than that of the Springfield Water Company. It is more 

 probable, however, that we -are merely dealing with the natural 

 variations of the streams. It seems fair to assume that the 

 two creeks are about on a par, since they are practically the 

 same size, ran through the same kind of territory, and appar- 

 ently have about equal chances of pollution. 



Another point of interest that may be mentioned is the 

 increase of chlorides and nitrates in the Hardcastle Well. This 

 well is situated on the edge of the town, and in a fairly well 

 built-up section. Having but one old analysis, however, with 

 which to make comparison, it is impossible to tell whether the 

 water has really deteriorated. The low required oxygen and 

 the high nitrates and chlorides in the water apparently indicate 

 a considerable previous pollution by sewage, subsequenth', 

 however, almost entirely oxidized before reaching the well. 

 The well is 50 feet deep, the lower 42 feet being through rotten 

 rock, which probably acts as a ver}^ efficient filter. There are 

 a number of cess-pools in the neighborhood, the nearest being 

 about 35 feet distant. The water is quite hard, containing 

 considerable calcium. C. M. Broo.mall. 



