IX.] CHEMISTRY OF NATURAL WATERS. 127 



the silica and the organic matters of this river-water will be 

 given further on ( 70, 71). It will be observed that while 

 the contents of all the other waters in this paper are given for 

 1,000 parts, those of the Ottawa are calculated for 10,000 parts. 



Water of the Ottawa River. 



Chloride of potassium . . . 0169 



Sulphate of soda 0188 



" potassium 0122 



Carbonate of soda 0410 



lime , 2680 



" magnesia 0690 



Iron-oxide, alumina, and phosphates traces 



Silica 2060 



In 10,000 parts ^ .6116 



47. It was an interesting question to determine whether the 

 composition of these various waters remains constant. Having 

 collected and analyzed, in September, 1847, the waters of three 

 springs in Caledonia, Ontario, belonging to Class III., and not 

 far from the spring of Class II. in the same town, noticed in 

 42, I again visited and collected for examination the waters 

 of the same springs in January, 1865, after a lapse of more 

 than seventeen years. The results, when compared as below, 

 show that considerable changes have occurred in the compo- 

 sition of each of these springs, and tend to confirm in an 

 unexpected manner the theory which I had long before put 

 forward, that the waters of the second and third classes 

 owe their origin to the mingling of saline waters of the first 

 class with alkaline waters of the fourth class. It will be 

 observed that the three Caledonia waters in 1847 were all 

 alkaline, although the proportions of carbonate of soda were 

 unlike. Sulphates were then present in all of them, but most 

 abundant in the Sulphur Spring, which, although holding the 

 smallest amount of solid matters, was the most alkaline. In 

 January, 1865, however, the first and second of these waters 

 had ceased to be alkaline, and contained, instead of carbonate 

 of soda, small quantities of earthy chloride, causing them to 

 enter into the second class. They no longer contained any 



