FEATURES OF THE ITHACA LAKE. 371 



channel is 10 to 15 rods wide, and is the smallest and shortest of the 

 ancient lake outlets so far seen by the writer.* 



The altitude of this outlet is not accurately determined, but is esti- 

 mated, by comparison with the railroad across the valley, at about 1,040 

 feet. 



Southeast of Ithaca, in the valley of Six Mile creek, the moraine is not 

 so well develo})ed as in Inlet valley, and has suffered much erosion. It 

 ends north of the divide, the heavy deposit reaching only to Caroline, 

 and the col being a mile further south in a long stretch of open valley. 



The divide is at the Bell schoolhouse, one mile south of Caroline sta- 

 tion, where the valley is nearly one mile wide between the rock walls, 

 and the swampy bottom is one-fourth of a mile wide. Including the 

 divide, and for considerable distance north and south, the valley bottom 

 is nearly level. The altitude of the Delaware, Lackawanna and AVestern 

 railroad at the crossing of the divide is 985 feet, which is perhaps 10 feet 

 above the low ground. The Beaver and Wilseyville creeks emerge from 

 ravines in the western rock-wall of the valley, and after nearly meeting, 

 part company, the former flowing north to join Six Mile creek, the latter 

 south to join the Cattatonk below Wilseyville. 



The head of the definite stream channel is about a mile below the 

 divide, at White Church station, with a Avidth of about one-eighth of a 

 mile and with walls perhaps 20 feet high. The tracks of the Delaware, 

 Lackawanna and Western and the Elmira, Cortland and Northern rail- 

 roads lie in the channel from White Church to below Wilseyville. At 

 Wilseyville the valley widens, and the channel is bordered by extensive 

 flood-plains (see figure 1, plate 23). 



DELTAS AND \VA TER-LE VE LS. 



Location and Height. — The deltas are not large compared with those of 

 the other glacial lakes and with the size of the valley, both branches of 

 which were lake outlets for a time — the detritus being borne south to the 

 Susquehanna basin. When the fall of the lakes reversed the drainage, the 

 inpouring streams from the cols spread their load over the many miles 

 through which the moraine stretches ; but the side streams have built 

 definite deltas. The most conspicuous near Ithaca are on the steep slopes 

 at Coy Glen (see figure 2, plate 23), Buttermilk, Enfield, and Newfield 

 ravines. The deposits of Fall and Cascadilla creeks are spread out on 

 the ]>lateau al)ove the campus of Cornell University. Other deltas are 

 seen at tlie mouths of streams down the valley or northward. 



In the valley of Six Mile creek are consi)icuous terraces of consi(leral)le 

 extent. There are two of these levels. The upper is above the White 



•The author is indebted to Mr G. K. Gilbert for indicating the location of this channel. 



