258 JESSE E. HYDE 



In the area under immediate consideration, central and southern 

 Ohio, the Bedford is from 90 to 100 feet thick, the Berea from 

 5 to 40 feet thick. In Scioto County on the Ohio large amounts 

 of sandstone are found in the Bedford, but this diminishes to the 

 northward so that there is much more shale in Pike and Ross 

 counties, while in Franklin County there is practically no sand- 

 stone, except in the upper 10 feet where very thin layers appear 

 in profusion. In Pike and Ross counties the sandstones are 

 frequently limy. When present, the sandstones are in beds from 

 a few inches to two or three feet thick, but the "shale" beds 

 intervening between such beds, often several feet thick, are largely 

 made up of very thin, hard, platy sandstones of which there may 

 be 12 or 18 in a foot. 



Exactly the same type of sandstone is found in the Berea of 

 central and southern Ohio as in the Bedford, except that the lime 

 disappears. In fact the Berea is distinguished from the Bedford 

 of the region almost solely by the rather abrupt diminution in the 

 amount of "shale." These shale beds are found to some extent in 

 the lower part of the Berea and, just as in the Bedford, they carry 

 the numerous, thin, platy sandstones. In other words, the litho- 

 logical change from the Bedford to the -Berea was almost wholly 

 one of amount and not of kind of material. 



THE OCCURRENCE OF THE RIPPLES 



Ripples are seldom noted in the lower part of the Bedford. 

 In southern Ohio they appear rather gradually near the middle, 

 and throughout the upper half of the Bedford and most of the 

 Berea they are present, sometimes in astonishing abundance. 

 The surface of each of the very thin lamellae of sandstone is rip- 

 pled, as well as of the thicker beds. In central Ohio they appear 

 first in the thin sandstones at the top of the Bedford, but are 

 confined almost wholly to the Berea. In central Ohio and as far 

 south as Pike County, the ripples gradually disappear in the 

 upper part of the Berea and they may be absent entirely in the 

 upper 10 or 15 feet, which also may become slightly coarser. 



Many localities can be found, especially in Pike County, where 

 the streams have cut into the Berea grit or the upper part of the 



