OF DENISON UNIVERSITY. 49 



tions to its upper sources with probably a vast river from the 

 ice sheet itself, found an outlet to the south through the gaps 

 between the rocky islands represented on Plate IV down the re- 

 versed lower Licking and Muskingum. As the valley of the 

 Muskingum was larger than that of the Licking it carried the 

 main volume of the stream and attained the greatest depth. 

 On account of the wall of drift at the Hanover dam, D, and the 

 stratified deposit filling the valley it has been suggested that 

 a lobe of the ice extended into the valley to this point and the 

 material was deposited from the water flowing from the ice and 

 as it was partially back water it formed a delta-like deposit 

 which only extended to the marshy area, M, back of this dam. 

 Where there was a current between the gaps this deposit was 

 not so deep, as is indicated by the lighter shaded portion. 



As already stated the watershed between the South Fork 

 of the Licking and the Scioto basin which extends west along 

 the county line, Plate III, is composed of morainic material. 

 After the retreat of the ice the Licking basin was closed and as 

 the waters rose in Lake Licking before they reached the level of 

 the top of the Reservoir dam or of the Hanover dam, they 

 reached a low col in the divide a little south of Hanover. The 

 position of this col is represented by the present Licking Nar- 

 rows. Its exact position was probably at the point represented 

 by c at the extreme left of Plates I and II. 



On each side of this low divide there was a ravine cut into 

 the Waverly conglomerate. As the water rose over the divide 

 and began to cut it down, the gorge produced by this cutting 

 to the west of the point c conformed exactly to the pre-exist- 

 ing ravine running in that direction as this ravine would repre- 

 sent continuously the lowest point in the divide ; hence we find 

 the upper part of the present gorge showing no marked changes 

 in its position. 



The ravine on the down slope towards the east, how- 

 ever, whose outline is represented on Plate I by the dotted line 

 and on Plate II by the crossed line, fared quite differently. A 



