176 The Ottawa Naturalist. [March 



not very palatable. If stored in vats or tanks these should be 

 of cement and frequently examined and cleaned. The water 

 for use should be passed through an efficient filter and boiling 

 would be an additional safeguard, though the presence of disease 

 germs would not naturally be expected. 



Upland Surface Waters. These constitute the waters of our 

 lakes and streams and are formed by the run-off from the lands, 

 though to some extent , of course, these sources are fed by springs. 

 By far the larger number of supplies of Canadian cities and towns 

 are drawn from lakes and rivers and hence the importance of 

 immediate and efficient legislation that will protect these natural 

 bodies of water from sewage and other pollution. The fact 

 should be emphasized that these natural waters are, almost 

 without exception, eminently suited without anv preliminary 

 treatment for drinking and domestic use. But as our popula- 

 tion increases and especially as cities and towns build up on the 

 margins of lakes and the banks of streams, the necessity of 

 adequate filtration becomes apparent. It will therefore be the 

 part of wisdom from this on, not only to protect these waters 

 from pollution as effectively as possible, but, also for those 

 communities drawing upon them for their supply to establish 

 filtration plants. Experience in other countries has shown that 

 despite the most vigilant protective measures such waters may 

 at any time, through accident or otherwise, receive excretal 

 waste and become a source of danger, a menace to good health. 

 It is now generally recognized by the highest authorities that 

 filtration is imperative a sine qua non if the supply is at all 

 seasons to be relied on as free from injurious bacterial life. 



The nature of the country and the composition of the 

 rocks of the catchment area will largely determine the character 

 of these waters. Thus a limestone district gives rise to a hard 

 water, a Laurentian area, with gneiss, granite and similar rocks, 

 result in a comparatively soft water. Again the colour 'of 

 these waters is largelv determined by the presence or absence 

 of swamps in the country from which they draw their supply. 

 A colored water, that is, one brown or yellowish-brown, through 

 the presence of dissolved peaty matter, though offending the 

 aesthetic sense (for we all prefer a colorless water), may be per- 

 fectly wholesome and especially so when such is from a large 

 body of quickly flowing water, as for instance the Ottawa river. 

 There are very few cases of illness or indisposition on record 

 if indeed any that can be definitely traced to the consumption 

 of these peaty waters from large, actively flowing waters, pro- 

 vided of course such have proven to be free from excretal 

 pollution. These so-called peaty waters and from sources such 

 as I have described, have shown themselves almost universally 



