12 Expedition to the 



ble, it is, perhaps, that the inclination of the rocks is towards 

 the most elevated summits in the vicinity. 



Laurel ridge, the next in succession, is separated from the 

 Alleghany by a wide valley. Its geological features are r in 

 general, similar to those of the eastern ranges ; but about its 

 summit the sandstones of the coal formation, begin to ap- 

 pear alternating with narrow beds of bituminous clay slate. 

 Near the summit of this ridge, coal-beds have been explo- 

 red, and, at the time of our visit, coals were sold at the pits, 

 for ten cents per bushel. In actual elevation, the coal strata, 

 at the summit of Laurel-hill, fall but little below the 

 summits of the Alleghany. Thus in traversing from east 

 to west, the state of Pennsylvania, there is a constant but 

 gradual ascent from the gneiss at Philadelphia, the seve- 

 ral rocky strata occurring one above another, in the inverse 

 order of their respective ages, the points most elevated 

 being occupied by rocks of recent origin, abounding in 

 the remains of animal and vegetable life. 



Near the summit of this ridge some change is observed 

 in the aspect of the forest. The deep umbrageous hue of 

 the hemlock spruce, the Weymouth pine, and other trees 

 of the family of the con iferse is exchanged for the livelier 

 verdure of the broad leaved laurel, the rhododendron, and 

 the magnolia acuminata. 



Chesnut ridge, the last of those accessary to the -i.llegha- 

 ny on the west, deserving the name of a mountain, is some- 

 what more abrupt and precipitous, than those before men- 

 tioned. This ridge is divided transversely by the bed of 

 the Loyalhanna, a rapid but beautiful stream, along which 

 the turnpike is built. Few spots in the wild and mountain- 

 ous regions of the Alleghanies, have a more grand and ma- 

 jestic scenery, than this chasm. The sides and summits of 

 the two overhanging mountains, were at the time of our 

 journey brown, and to appearance almost naked; the few 

 trees which inhabit them, being deciduous, while the laurels 



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