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No, I.] GEOGNOSTICAL OBSERVATIONS. 521 



universally formed of naked smooth rock, and generally of a species of 

 durable red granite that has been more than once mentioned as composed of 

 well crystallized reddish felspar and grey quartz. Large irregular, but some- 

 what cubical, fragments of this rock are scattered over the surface of the 

 hills, or rest upon their very summits, by two or three angular points, as if 

 left exposed there by the decay of the less durable material that enclosed 

 them. A remarkable instance of this occurs about a mile and a half to the 

 southward of Fort Enterprise, on a hill which is thence termed the Big Stone 

 Bill. This hill, which is the highest for many miles, rises from six to eight 

 hundred feet above Winter River. The acclivities of the hills, generally speak- 

 ing, consist of gneiss wrapped in a mantle form round the granite, These accli- 

 vities are more or less thickly covered with a coarse gravelly soil, and very 

 often exhibit accumulations of large cubical fragments of gneiss, which fall 

 from small mural precipices. In the upper parts of the inclined valleys, at the 

 base of the hills, there is commonly a very thin layer of mountain peat, but 

 the bottom of almost every valley is occupied by a lake. Most of these lakes 

 communicate with each other only when flooded by the melting snow, and 

 many of the smaller ones are entirely land-locked ; they all contain fish. On 

 the borders of the formation, where a few trees exist, the white spruce is 

 confined to the sandy soil that is partially accumulated on the banks of the 

 streams. A few birches sometimes grow amongst the large stones on the 

 banks of a rapid, and two or three stunted black spruces now and then occur 

 on the peaty spots. 



It may be proper to mention the localities of some of the rocks about Fort 

 Enterprise, where we had the best opportunity of examining this formation. 



The strata at the base, and on the acclivities of the Big Stone Hili already 

 mentioned, consist of granitic gneiss, its summit of red granite. A hill about 

 a mile to the S. S. W. of this, composed of gneiss, dipping S. E. b. E. at an 

 angle of 70°, presents a mural precipice of red granite traversed by a thick 

 vein of augite green-stone ; one portion of the vein may be termed basaltic 

 augite green-stone. Half a mile further, in the same direction, there is a 

 mural precipice, the loftiest in the neighbourhood, being one hundred and 

 twenty feet high, which is formed of red granite, alternating with granitic 

 gneiss. In a dilatation of Winter River, termed by the Indians the Lake of 



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