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PROCEEDINGS OF PHILADELPHIA MEETING. 



Potomac Formation 



Professor Tuome}' described in considerable detail many of the more prominent 

 outcrops of this formation in the southern portion of the state, but, as explained 

 above, regarded it as the lower member of the Eocene. It outcrops in a belt four 

 or five miles in width which extends from Augusta, Georgia ; through Aiken ; south 



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of Lexington ; through Columbia, and, I find, continuously into Xoi-th Carolina 

 via Camden and Cheraw. The basal beds are mainly coarse sands, with pebbles, 

 which to the southward are sometimes consolidated to a soft sandrock. Finer 

 sands and clays occur higher up in the formation, and it is these that are usually 



