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CHARLES S. PROSSER 



ing publication of reports by the Ohio Geological Survey, led 

 the state geologist, Professor Edward Orton, Jr., to request a 

 revision of the geological scale of the state for these reports. 

 In compliance with the above request, the following scale has 

 been prepared, which in its preliminary form is now submitted 

 for discussion. The writer will be pleased if geologists familiar 

 with the Ohio formations will communicate to him their opinions 

 in regard to this classification or any part of it. Such communica- 

 tions will be retained, duly considered, and credited in an extended 

 discussion of this subject which the writer has in preparation. 



GEOLOGICAL SCALE OF OHIO. 



