146 Bulletin of Laboratories of Denison University. Vol. XIII] 



while rather plain-Hke in surface, is contiguous to morainic to- 

 pography. 



From the vicinity of Boston Corners to the easternmost reach 

 of the ice-tongue we have a recessional period of drift accumula- 

 tion during which the ratio of the supply to the melting factor 

 was a little less than unity; but in the neighborhood of the 316- 

 foot well (Fig. 3) there is evidence of a stationary condition of the 

 ice. Through this whole distance, kettles are quite common, some 

 of which are designated on the topographic map. Extending 

 eastward from this deep well there is a marked morainic ridge, 

 for a ways simulating in its form an esker, but gradually broaden- 

 ing into the mass of very irregular drift in which the loop ter- 

 minates (Fig. 5), reaching about one mile into Muskingum 

 County where glacial drift in situ has not been previously re- 

 ported. 



To account for this ridge ithere are two suggestions : The ice- 

 front drainage in the direction of Black Run. which lies just ofP 

 the northeast corner of the map, may have been sufficiently vigor- 

 ous to remove most of the debris collected from the melting ice ; 

 it will appear in later discussion that there was active drainage 

 in this direction. Or the load of rubbish carried by this valley 

 dependency may have been much greater on its southern side ; the 

 rock spur on either side of Hanover offered ample obstruction to 

 the progress of the ice to encourage acquiring a load. 



An analogous arrangement of rock spurs is noted on the op- 

 posite side of the valley ; here, however, it is apparent that the 

 tributary valleys were occupied by laterals from the ice-tongue, 

 thus lessening its power of erosion. The low area in which Han- 

 over lies was not similarly filled with ice for the reason that its 

 approach from the north is an almost continuous wall of rock 

 '(Fig. 8), save where the Rocky Fork has incised it. This wall was 

 doubtless considerably lowered by ice-erosion as there is but lit- 

 tle Logan sandstone capping it, and apparently some of the Black 

 Hand in places was also carried away. So it seems that the condi- 

 tions for acquiring a greater load of rubbish were in favor of the 

 south side of the tongue of ice that fed eastward through this 

 valley. 



