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BOARD OF AGRICULTURE. [Pub. Doc. 



high in a surface water they point to continuous pollution. 

 When, however, the chlorine is not much above the normal 

 in waters which show high free ammonia and nitrites, the 

 inference to be drawn from these products of decomposi- 

 tion is that we have to do with pollution from farm-yards 

 or from manured fields, — a distinction which it w, fre- 

 quently very important to make. 



Deductions drawn by the chemist are based upon the fact 

 that, in waters where the chlorine is due to organic contam- 

 ination, he finds present at the same time free ammonia as 

 well as nitrites ; or, in other words, where all three are 

 found present in any water in a degree much in excess of 

 the normal, it is an indication at once that it is from a con- 

 taminated source, and not fit for consumption. In our 

 work upon the investigation into the sanitary condition of 

 our farm buildings we have made analyses of some twenty- 

 five samples of water, taken from a large number of towns. 

 The results of these analyses show as follows : — 



Water Analysis. 



