78 Bacteria in Relation to Country Life 



The quality of organic matter. — It has already been 

 noted that the amount of organic matter in river^water 

 is of paramount importance from the bacteriological 

 standpoint. Something should also be said concerning 

 the quaUty of the organic matter. There are streams 

 whose waters are brown or almost black on account of 

 the peaty or other vegetable matters dissolved in them. 

 Many such streams furnish a clear, wholesome drinking- 

 water in spite of the high content of organic matter. 

 This is true of some rivers along the Atlantic seaboard. 



It seems that the organic matter derived from swamps 

 does not decompose as readily as the organic matter 

 derived from sewage. In fact, the organic substances 

 in such waters may exert, to a certain extent, pronounced 

 antiseptic properties, like those of the peat itself. , The 

 development of bacteria in such water must necessarily 

 differ from that in water deriving its organic matter 

 from sewage. The value of the two from the sanitary 

 standpoint must, likewise, be different. However, 

 experts do not entirely agree as to the wholesomeness 

 of peaty water for drinking purposes. Instances are 

 cited when such water has been used for years without 

 ill effects. Instances are likewise cited when the general 

 use of peaty water has led to a markedly increased 

 mortality from intestinal diseases. 



Alkali water. — But little is known of the bacteriology 

 of waters charged with alkali salts. Such waters are 

 used for drinking purposes when the content of alkali 

 is not too high. Apart from their somewhat laxative 

 effects these waters do not appear to be detrimental 

 to health. 



