64 



nute cells, containing hematitic oxide of iron. Nearly the whole of 

 the principal peak of the mountain is made up of this beautiful rock, 

 which, rising in the form of a wedge to the height of several hun- 

 dred feet, presents a narrow wall of nearly vertical strata along the 

 summit. The dip is west, and the fragments which have tumbled 

 to the eastern base have rendered this the easiest direction of ascent. 

 From its hardness, and the indestructible nature of its materials, 

 this gneiss will some day possess a value independent of that found- 

 ed upon its colour, which will bring it into use as an article for 

 building. At the base of the mountain schorl occurs in great abun- 

 dance, crystallized in long prisms in quartz. Asbestus and kyanite 

 are also found together, with several other minerals chieily inte- 

 resting in a scientific point of view. 



Westward of this belt of gneiss the rocks assume various inter- 

 mediate characters, until at length the truly crystalline structure is 

 lost, and numerous forms of slate of very peculiar and equivocal 

 features make their appearance. At what precise points the rocks 

 of unequivocally primary character terminate, future researches 

 must ascertain. 



In pursuing the line selected for the accompanying profile, the 

 gneiss, which is found dipping east for some distance beyond the 

 western edge of the bituminous coal formation, assumes a western 

 dip which it again changes for an eastern one, after which another 

 change occurs, and the western dip now continues to the neigh- 

 bourhood of Columbia. Between this point and Brcmo, the rocks 

 become vertical, and further west, the dip continues with scarcely 

 any exception, easterly, but very steep as far as the South-west 

 mountain, and even in many lines almost without alteration, to the 

 western base of the Blue Ridge. 



The soils of the primary region, except were the rocks accompa- 

 nying the coal exist, are remarked for the quantity of clay, often of 

 a very ferruginous character, which they contain. The felspar, 

 which, as already remarked, enters largely into the composition of 

 our gneiss and granite, is in some of its forms peculiarly liable to 

 undergo a decomposition by exposure to the atmosphere. The 

 alkali contained in it is gradually dissolved out, and the clay and 

 silica, its other constituents, fall to powder, and thus furnish the 

 materials for soil. At the same time, the quartz and mica, no longer 

 cemented by the interposed felspar, also separate and mingle with 

 the general mass of clay or sand. The Hornblende possessing 



