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DESCRIPTION OF THE COUNTRY 



At the point opposite the foot of the rapids, the range is two hundred and forty- 

 four feet high ; and at a point on the southern side of the range, measured by Colonel 

 Whittlesey, he found it to rise one hundred and seventy-four feet above the level of 

 the lake. At the "fall" spoken of, the rock (No. 522) is bedded, the beds in- 

 clining 46° west-southwest, while the bearing of the range is northeast and south- 

 west. The beds are from ten inches to three feet thick, and are traversed by joints 

 having all the regularity and appearance of cleavage planes. Between some of the 

 beds are thin seams of mica slate, and a few thin seams of quartz were noticed, but 

 no veins of any description were seen. Some of the beds are very decomposable, 

 being made up principally of felspar, which is in large crystals, which cohere but 

 slightly. No. 523 occurs about two hundred and fifty yards below the " fall ;" No. 

 524 is from the middle ridge, and shows the general character of the rock; No. 525 

 is from the top of the high ridge at the foot of the rapids. 



Soon after leaving the rapids the shores of the river were found lined with the 

 rice plant ; and the clay-beds, which made their appearance on the northwest side 

 of the last granite range, were occasionally exposed above the water. Between the 

 range, and the mouth of Crane River, there are frequent hills and low ridges, in all 

 of which granitic and metamorphic rocks were seen. About a mile and a half 

 above Crane River, is a ridge of gneiss and mica slate (Nos. 526 and 527), tra- 

 versed by veins of granite ; and a short distance below that stream is a ridge of mica 

 slate (No. 528), which rock is seen occasionally for the next two miles, when we 

 came to rapids, about three hundred yards long, between perpendicular walls of rock 

 of considerable height. On the north side of this ridge is a heavy deposit of dark, 

 yellow, tenacious clay. 



As far down as the " Falls of Vermilion," the rocky exposures are frequent, and 

 consist of schistose and granitic rocks, like those already described. The tops of 

 some of the higher ridges are bare, and display most beautifully the ramifications of 

 the granitic veins through the mica slate. The veins are from half an inch to 

 twenty feet in width, and composed sometimes of quartz alone, or of felspar alone, 

 or of a mixture of quartz and felspar, very few being true granite. In some places 

 the mica slate and granitic rocks are so intermingled, that it would be difficult to 

 determine which predominates. No. 529 shows the general character of the mica 

 slate, and No. 530 of the veins which traverse it. At several points there are dome- 

 like intrusions, of a granitic character. 



The river bottoms bear soft maple, elms, and oaks, the hills and ridges being 

 covered with yellow pine, cypress, spruce, and poplar. In the expansions of the 

 river wild rice grows. 



September 5. The fall which we reached last night, is said to be the highest on 

 this river. It was measured by Colonel Whittlesey, and found to be thirty-one and 

 a half feet, including the rapids above and below. The principal fall is between 

 vertical walls of mica slate, about six feet apart. At the upper chute, the highest 

 perpendicular cascade is eleven feet. After leaving the falls, the rocks, which are 

 rather more thinly laminated than usual, dip south-southeast, at an angle of 35°. 

 Half a mile below, the river is contracted to twenty-five feet in width, and runs be- 

 tween vertical walls of mica slate for the distance of one hundred and twenty yards. 



