4# 



UNITED STATES 



regular strata of these rocks : 3dly, fossil shells un- 

 known in these seas, the clam and scallop excepted, 

 and found on their summits in 2^1 argUiaceous or in 

 a siliceous bed. -iHNHP^ 



Out of the granitic region, softrre exceptions exist, 

 the most remarkable of which are: 1st, the moun- 

 tains between Harrisburgh and Sunbury on the Sus- 

 quehannah, composed in great part of granite ; 2dly, 

 a vein of talky granite,| or Muscovy glass; Sdly, 

 numerous blocks at the foot of the south-west 

 chain in Virginia, particularly near Milton on theRi-. 

 vannah. 



2« Region of Sandstone* 



The sandstone of Kaats Kill forms the distinguish* 

 ing character of the second region or diversity of 

 soil, ifhich comprises all the mountainous country of 

 Blue Ridge, Alleghany, and Laurel Hill, the sources 

 of the great Kanhaway, the knot or arch of the Al- 

 leghanies, and in general all their chain to the south 

 as far as the angle of Georgia and the Apalachians. 

 The traces of it are lost to the west in the state of 

 Tenessee, and the chain of Cumberland, audits con- 

 tiguity to the calcareous region cannot be assigned 

 Avith precision. In the north and north-east its 

 limits appear to be the sources of the Susquehannah, 

 even those of the lakes of Genessee, and in general 

 the right banks of the Mohawk and Hudson. Dr. 

 Barton, who on his return from a journey to Niaga- 

 ra, in 1797, CT'ossed the whole of upper Pennsylva- 

 iQiia, never lost sight of sandstone from Tioga to withia- 



