156 CHEMISTEY OF NATUKAL WATEES. [IX. 



Calciferous, while two others, at Ste. Martine and Rawdon, 

 appear to have their source in the Potsdam. All the other 

 waters of these two classes issue from the Hudson River shales, 

 with the exception of those of Varennes and Jacques Cartier, 

 which seem to rise from the Utica formation. 



Of the waters of the second class, of which about thirty have 

 been examined, some five or six issue from the shale formations 

 Nos. 5 and 6, but all the others are from the underlying lime- 

 stones. The bitter salines of the first class flow from the lime- 

 stones of the Trenton group, with the exception of one at 

 Ancaster, which is from a well sunk in the Niagara formation, 

 and that of St. Catherine's, from a boring carried through the 

 Medina down into the Hudson River shales. The source of 

 both of these is probably, like that of the other very similar 

 waters, the underlying limestones. 



76. From this distribution of the waters of the first four 

 classes it would appear that the source of the neutral salts, 

 which consist of alkaline and earthy chlorides, is in the lime- 

 stones and other strata from the Potsdam to the Trenton inclu- 

 sive, while the alkaline carbonates are derived from the argilla- 

 ceous sediments which make up the Utica and Hudson River 

 formations. The sediments are never deficient in alkaline sili- 

 cates, whose slow decomposition yields to infiltrating waters 

 (13) the alkaline carbonates which characterize the mineral 

 springs of the fourth class. These, mingling in various propor- 

 tions with the brines which rise from the limestones beneath, 

 produce the waters of the second and third classes in the man- 

 ner already explained. The appearance of several springs of 

 the third class, as those of Caledonia and Fitzroy, from these 

 lower limestones, is not surprising, when it is considered that 

 the Chazy formation in the Ottawa Valley includes a considera- 

 ble thickness of shales, sandstones, and argillaceous limestones, 

 approaching in composition to the sediments of the Hudson 

 River formation. 



77. As an evidence that the different classes of waters 

 have their origin in different strata, may be cited the fact that 

 springs very unlike in composition are often found in close 



