662 II. L. ALLING— GLACIAL LAKES OF CENTRAL ADIRONDACKS 



these features — the Grcnvillc, the granite intrusive, the trap dikes, the 

 faulting, and, lastly, the Pleistocene river channel ! 



Upper Jay Lake (altitude, 1,000 feet). — Eeturning to the description 

 of the glacial lakes that existed in the valley of the East Branch, we find 

 that the lake succeeding Wilmington left terraces at the present height 

 of 1,000 feet. This has been called "Upper Jay Lake," and, like its 

 predecessor, is very clearly defined. A wave-built spit at the foot of the 

 Spruce Hill road near Norton Cemetery is exactly 1,000 feet in altitude, 

 while a beach with a height of 1,030 feet, situated 1 : >4 miles ' southwest 

 of North Jay, furnishes a basis for calculating the amount of warp, the 

 figure being 2.79 feet per mile. The outlet of the lake is not definitely 

 known, but a pass half a mile directly south of Haystack Mountain, in 

 the Ausable quadrangle (not the mountain of the same name in the 

 Marcy Bange), lias an altitude that gives us the proper figure when the 

 deformation is computed. When visited, however, this pass did not show 

 evidences of stream-work. The area is entirely fine sand, while farther to 

 the northeast remains of crescent-shaped moraines stretch part way across 

 the. valley. A possible channel iy 2 miles north of Bald Mountain is sug- 

 gested as an alternative outlet. 



The lakes .following the Upper Jay Lake are very numerous and close 

 together. Those described below, with their attached names, probably 

 represent only part of the series, for the territory is rough and progress 

 in the field is slow. Nevertheless they illustrate the fascinating Pleisto- 

 cene history of this unusual country. They descend from 980 to 500 feet 

 in altitude through the following steps: 980, 960, 935, 870, 840, 760, 680, 

 and 500 feet. They will be treated briefly. 



Haselton Lake (altitude, 960 feet).— A lake with the altitude of 960 

 feet around the town of Keene has left terraces, wave-cut cliffs, and 

 beaches. The amount of warp based on beaches 1% miles southwest of 

 North Jay and faint terrace cuttings on a hill near Keene is calculated 

 at 2.63 feet per mile. Relatively small sand plains of this period are 

 well shown about the town of Haselton Village in the Lake Placid sheet. 

 ■ The controlling outlet is unknown, but the writer offers the suggestion 

 that it may have been a one-bank channel on the north side of Haystack 

 Mountain (Ausable' sheet) carrying the waters east to the ice-tongue. 



Lower Jay Lake (altitude, 935 feet). — This lake is very definite and 

 splendidly exhibited about Keene by several beaches situated at the lake 

 level and by wave-cut terraces at 931, 935, 933% feet, as determined by 

 spirit-leveling. Farther north: it becomes faint and no terraces or beaches 

 have been found on Avhich deformation can be based. There is, however, 

 a fine sandy plain of this lake on the western edge of the Lake Placid 



