THE PREGLACIAL DRAINAGE OF OHIO. 29' 



Morgan county line and the Meigs Creek col. These latter waters 

 crossed into the Wolf Creek valley through the gap south of Rox- 

 bury and thence southward through the old valley at Layman 

 into the Little Hocking. 



Below the mouth of the Little Hocking the old stream 

 passed through the old valley floor at Torch, crossed the Hock- 

 ing at Coolville and thence through the old valley at Tupper's 

 Plains into the basin of Shade River. At Coolville it receives a 

 short tributary, along the line of the Hocking which headed at 

 the col below the mouth of Federal Creek. 



Along the line of the present Middle Fork of Shade River the 

 old stream received the waters from the section of the Hocking 

 blow the Athens col, including also those of the Federal Creek 

 basin. These waters crossed the ridge through the gap south 

 of Guysville. Concerning the further course of this old river it 

 may be stated that since the work was completed which forms 

 the basis of this report, much more field work has been done and 

 it is known that the old river passed westward across southern 

 Ohio and found its way into the Scioto. A more detailed report 

 is now in preparation covering the entire history of this old 

 valley. The normal characters of this old system are shown on 

 the map Plate VI, which presents the old drainage separated 

 from the present. It is noticeable that this old normal drainage 

 conforms very closely to the slopes of the old upland surface. 



THEORETICAL CONSIDERATIONS. 



Within the limits of this paper it is not possible to discuss 

 at length the probable factors involved in the production of the 

 modifications of drainage from this old restored system to the 

 new or present form. However, it may not be out of place to 

 offer a few suggestions of a theoretical nature with the 

 hope that they may be helpful in the further study of 

 the phenomena themselves. The first and most natural 

 question that arises is, if the restoration, as worked out, 

 truly represents the conditions of drainage prior to the pres- 

 ent, what produced the change? The answer to this question 

 may not be found in the study of so limited a field and the phe- 

 nomena therein presented. From the work previously done in 



