296 THE CANADIAN NATURALIST. [Aug. 



Silurian limestones is not surprising, when it is considered that the 

 Chazy formation in the Ottawa valley includes a considerable thick- 

 ness 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 proximity, and 

 apparently rising from a common fissure or dislocation. Thus in 

 the seigniories of Nicolet and Labaie du Febvre, I have examined 

 six springs, all of which rise through the Utica formation along a 

 line, in a distance of about eight miles. Of these springs two be- 

 long to the second, two to the third, and two to the fourth class ; 

 these last being probably derived entirely from the shales, while 

 the others have their source in the underlying limestones, and are 

 more or less modified in their ascent. Again, at Sabrevois, within a 

 few feet are two springs of the second class, of which one contains 

 salts of baryta and strontia, and the other soluble sulphates. In 

 like manner at Ste. Anne, in the Quebec group, a spring of the 

 second class and one of the fourth are found not far apart. The 

 springs of Caledonia offer another and not less remarkable example. 

 In 1847 there were to be seen, not far from a spring of the second 

 class, three others of the third class very near together, one of them 

 sulphurous, but all sulpbated, and differing in the proportions of 

 carbonate of soda present. In 1865, while one of these still re- 

 tained its character of a sulphurous sulphated water of the third 

 class, the others were changed to waters of the second class, and 

 held salts of baryta in solution. These relations, which we have 

 already pointed out (§ 47), not only show waters holding incom- 

 patible salts issuing from different strata along the same fissure, 

 but mingling in such varying proportions as to produce from time 

 to time changes in the constitution of the resulting springs. 



§ 78. The temperature of none of the springs which we have here 

 described exceeds 53°, which has been observed for two springs at 

 Chambly, about twelve miles from Montreal. Inasmuch as the 

 mean temperature of this city, as deduced from the observations of 

 twenty-seven years, is 44°. 67, the Chambly waters are to be 

 regarded as slightly thermal. No other springs in Canada are known 

 to present so high temperature, unless possibly the acid waters 

 of the fifth class, for which we have pointed out the importance 

 of farther observations (§ 48). The St. Leon spring was found 

 to be 46°, and that of Caxton, 49° F. 



