NORTHWEST SHORE OF LAKE SUPERIOR. 



371 



The general course of Cariboo River is south, and, as far as explored, is a succes- 

 sion of cascades, with perpendicular walls of rock on each side. The chasm through 

 which it flows is from eight to twenty-five feet in width, and from sixty to eighty 

 feet in depth. The bearing of the range is from northeast to southwest. After 

 ascending the bluff at the mouth of the river, there is a very gradual rise for three- 

 quarters of a mile, to the height of one hundred and forty-eight feet, where the first 

 ridge begins, the summit of which is three hundred and thirty-four feet above the 

 level of the Lake. Following up the stream, which flows in a gorge cut through 

 this ridge and a spur of the succeeding one, for a mile and a quarter, No. 189 ap- 

 pears in the bed of the stream, at an elevation of three hundred and four feet. This 

 rock, of which there is one hundred and twenty feet exposed at the falls, does not 

 differ from similar beds at other places, except in being highly charged with car- 

 bonate of lime in some of the beds. The conglomerate exposure at the same place 

 is eighty feet thick, with beds of siliceous shale intercalated, and resembles, in this 

 respect, the conglomerates seen on Kagitshiwaninawak and Black Rivers, already 

 described. The contained pebbles are, some of them, very large ; and although 

 many of them are angular, and give to the rock somewhat of a brecciated appear- 

 ance, they are mostly rounded, and have a weathered aspect. Among them I 

 noticed amygdaloid, slate, greenstone, and jasper. The paste in which they are 

 embedded is calcareo-ferruginous, effervesces freely with acids, and contains a large 

 percentage of iron. 



Beneath the conglomerate is an altered clay-slate, the upper part of a steel-gray 

 colour, and much indurated, but breaking in the lines of deposition as well as 

 cleavage with facility. This rock gradually changes as it descends, and finally be- 

 comes metamorphosed into a dark reddish-coloured, jaspoid rock, extremely hard, 

 with an irregular sharp fracture, and containing many small nodules of blood-red 

 jasper. At the point where this section occurs, which is about two miles from the 

 Lake, is a fall of one hundred and twenty feet, in three cascades, which exposes the 

 contact of the different rocks in the most satisfactory manner. The wood engraving 

 that forms the frontispiece to this Report, on page 208, from the pencil of Major 

 R. Owen, represents the fall and escarpment of two hundred feet, through which 

 Cariboo River descends to the Lake. 



The principal rock on the lake-shore, between the mouths of Cariboo and Two 

 Island Rivers, is No. 630 ; associated, however, at many points, with other beds. 

 The bay into which Cariboo River empties has a shingle beach, covered with large 

 boulders, except toward the west end, where there is an exposure of from five to 

 six feet of amygdaloid ; and then, for one hundred yards, an escarpment thirty feet 

 high, where the amygdaloid is overlaid by No. 630. The same rocks are seen at 

 the point between this and the next bay below, twenty feet in height. The second 

 bay has a shingle beach, without any rock exposure. At the point below, however, 

 the same rocks occur in an escarpment thirty feet high, and dipping to the south- 

 east, at an angle varying from 17° to 28°. In the third bay there is an exposure 

 of five feet of rock, and at one point there seems to be a basaltic bed underlying the 

 amygdaloid. Back of this bay, at the distance of about three-quarters of a mile, 

 the ridge through which the gorge on Cariboo River is cut, passes in its northeast- 



