110 



About ten years afterwards Dr. Wigner published, in the 

 " Sanitary Record," the results of analyses of the water supplies 

 of various health resorts, that of the Dover water appeared in 

 September, 1877. It was as follows : — 



The next Table to which I shall draw your attention, embodies 

 the results Dr. Glaistcr obtained last year. He states his results 

 in parts per 100,000, but I have reduced them to grains per gallon, 

 for the sake of comparison with the others : — 



Now having had your attention drawn to the results of these 

 analyses you will easily understand the bearing of what follows on 

 this subject. 



When the comparatively pure water falling as rain reaches 

 the ground, it comes in contact with decaying vegetable and 

 animal matter. If there is much of the latter the water takes up 

 the products of its decay and becomes rich in Nitrogen compounds, 

 that is to say. Nitrates, Nitrites and Ammonia. Water, therefore, 

 which contains large quantities of these bodies is, generally speak- 



J 



