46 



UNITED STATES. 



limestone of the west, and that of these two districts 

 to the east : the first is, that the substance of the cal- 

 careous strata in the east is generally of a pretty- 

 deep blue colour, interspersed with numerous white 

 veins of quartz ; while the substance of the great cal- 

 careous stratum in the west, particularly in Ken- 

 tucky, is of a grey colour, and a homogenous and fo- 

 liated texture, 



The second difference is, that the stratum in the 

 west is nearly horizontal, forming a kind of general 

 table under the whole country : on the contrary in 

 the east, there is in the counties of Botetourt, Rock- 

 bridge, Staunton, Frederick, York, Lancaster, and 

 as far as Nazareth, the limestone generally lies in a 

 state of confusion, and as it were jumbled together 

 by violence : with this singular trait, that in the val- 

 ley between the North Mountain and Blue Ridge the 

 angle is always less, that is below 45 deg. while in 

 the counties of Lancaster, York, and Frederick, the 

 mountains excepted, it is more habitually above 4^ 

 deg. ; which refers also to all the other strata, whe- 

 ther of granite or sandstone, viz. being less inclined 

 in the mountains, than as they approach the sea. At 

 the cascade of the Schuylkill, near Philadelphia, the 

 inclination of the strata of talcky granite is 70 deg. 

 on the Hudson it reaches as far as 90 deg.* 



From these last-mentioned facts we are authorised 

 to conclude, that the whole of the Atlantic coast has 

 been deranged by earthquakes, while the country 

 west of the Alleghanies has not been disturbed. Dr» 



The diiference in the position of the strata on the east and west 

 sides of Alleghany has been often mentioned before Volney, and is 

 particularly noticed in the Columbian Mag, Philad. 1786. 



