PHENOMENA OE BUTTERNUT VALLEY 63 



discussion, it should be remembered that previous to this time all the 

 glacial waters to the west of this meridian, except the primary local lakes 

 and lake Newberry (which lakes flowed south across the divide) were 

 drained westward, ultimately into the Mississippi. But during that time 

 of westward flow lake Warren had crept eastward along the ice-front as 

 far, probably, as the Onondaga valley, with a surface elevation between 

 880 and 900 feet, and the local lakes had one by one been destroyed 

 by lowering into the invading Warren waters. The Mohawk valley was 

 now apparently cleared of ice, at least sufficiently to allow of eastward 

 drainage to the ocean, which then occupied the Hudson valley. The 

 critical locality, where the glacier last dammed the Warren waters from 

 eastern flow, seems to have been east and west of Jamesville. When 

 the ice-front over the Butternut and limestone valleys receded as far as 

 Jamesviile, the Warren waters found their first eastward escape toward 

 the Mohawk, and all the waters of the Finger lakes region were suddenly 

 diverted from westward flow to eastward How. 



The earliest eastern outlet of lake W^arren extinction was possibl}^ the 

 Reservoir channel, the Warren waters standing in the Otisco and Onon- 

 daga valleys. If it was the Greens channel, then the Warren waters were 

 also occupying the Butternut valley. But with the down-cutting of the 

 eastern outlets the waters lowered upon the pass over the Corniferous 

 escarpment west of Marcellus, at the head of the Gulf channel, and this 

 became for considerable time the topmost wasteweir of the series of east- 

 ward-leading channels. 



The later waters held in the Butternut valley, contributed successively 

 by the three gTeat channels leading from the Onondaga on the west, may 

 be called the glacial Jamesville lake. Its level was falling as the eastern 

 outlets changed. 



The east-and-west ice-front was probably so close to the rivers flowing 

 east through the Jamesville channels that the waters were practically 

 forced across the narrow Butternut valley and the land eastward, and 

 we find corresponding channels to Limestone valle}^, which will now be 

 described. 



CHANNELS LEADING EAST FROM BUTTERNUT VALLEY 



The earliest of these waterways has been already described as the 

 Greens channel (page 62). If this carried Warren waters, then it was 

 the first eastward escape, and it was not in continuation of any river 

 flow from the west. The water brought into the valley by the Reservoir 

 channel during the early life of the latter was carried out by a channel 

 one and one-half miles east and northeast of Jamesville. At the second 

 road corners east of the village this may be seen as a broad scourway in 



