Rocky Mountains. 299 



tified in finding an extensive bed of native magnet, which 

 seemed to be embraced in the granite. Not far distant the 

 same rock contained large masses of pyrites, and of bluish 

 green mica. In these we readily perceived the blue vitriol, 

 and native copper, mentioned by our host. In some places 

 we found the bed of the brook paved almost exclusively, 

 with detached schorls. We collected also several other in- 

 teresting imbedded minerals. More extensive examinations 

 will hereafter show this spot to be one, among the most in- 

 teresting in America, to a mineralogist. The great depth 

 of soil resting upon this formation of granite, prevented our 

 examining it at as many points as we could wish, also from 

 ascertaining to our satisfaction its extent, and its connexion 

 with the neighbouring rocks. It appears, however, at seve- 

 ral points in an area of fifteen or twenty acres, and always 

 in place. We saw not a single boulder or detached mass at 

 any distance. This may be owing in part to the perishable 

 structure of the granite, and in part to its being surrounded 

 on all sides by more elevated rocks of slate or sandstone. 

 On the summit of the hill a grave had been recently dug. 

 In the granitic soil which lay about it, we saw many frag- 

 ments of pyrites, also uncommonly large and beautiful lami- 

 nae of talc, intermixed with scales of mica. These two mine- 

 rals are, we think rarely found in such intimate connexion, 

 yet retaining so perfectly their distinctive characters, as in 

 the instance under consideration. The talc sometimes forms 

 an integrant part of the granite and we have seen it blended 

 with mica in the same specimen. 



The road leading towards the Little Rock, on the Arkan- 

 sa, passes from the granite of the Cove over a coarse hard 

 sandstone, embracing beds of conglomerate or pudding stone, 

 and in many respects closely resembling some of the varie- 

 ties of the old red sandstone of the Alleghany mountains. 

 Towards the east the surface of the country rises gradually, 

 at\d the sandstone, without giving place to any other stratum. 



