664 H. L. ALLING GLACIAL LAKES OP CENTRAL ADIRONDACK^ 







which the Ausable Branch of the Delaware and Hudson Railroad has 

 made a deep cut. Here the level is like a table, and beautifully shown 

 by the contouring on the map. This plain very probably represents the 

 summit marine level of Professor Fairchild. The figure he has secured 

 for this locality is 650 feet, which is 30 feet lower than the writer's. This 

 discrepancy in elevation may be due to a grading up of the plain from a 

 lower base level farther down the valley. 



Keeseville water level (altitude, 500 feet). — On the junction corners 

 of the Ausable, Willsboro, Plattsburg, and Daimemora quadrangles an 

 extensive delta plain exists with an altitude of 500 feet. Beaches of Hi is 

 delta have been noted and mapped by Woodworth. 16 It seems fairly cer- 

 tain that this Keeseville level is marine in origin. 



ELIZABETHTOWN GROUP 



General observations. — Although the Elizabethtown group of glacial 

 lakes is, perhaps, just as interesting as those in Keene Valley, it has not 

 received the attention that it deserves. Several of the lakes have been 

 observed and described by others, notably Dr. Heinrich Ries and Dr. 

 William J. Miller, but the higher levels, the writer believes, are new io 

 geological science. 



Rhododendron Lair (altitude, 1,G30 to 3,650 feet). — The highest glacial 

 lake terraces so far discovered are situated in the Elizabethtown sheet in 

 the Chapel Pond pass (Keene Township), in the neighborhood of Rho- 

 dodendron Pond. Several destructive forest fires have swept through 

 this fault valley in the past few years, rendering the region forbidding, 

 but at the same time revealing the splendidly developed terraces lying at 

 the altitudes of 1,630 to 1,650 feet. They are, as a rule, exceedingly 

 bouldery and rough. They give the impression that they are morainal 

 ridges modified by standing waters. 



Bouquet Lake (altitude, 1,530 to 1,550 feet). — In the same region 100 

 feet lower we find another group of terraces of similar character. The 

 extent of the lake is somewhat problematical, but it is supposed to have 

 been considerable, in view of some indistinct terraces observed 2 miles 

 northwest of Lewis (in the Ausable sheet) at 1,670 to 1,690 feet, which, 

 if they belonged to this same lake, would indicate a deformation of some- 

 thing like 3 feet per mile. 



Branch Lake (altitude, 1,300 to 1,340 feet).— Four miles west of Eliza- 

 bethtown, in the Valley of the Branch, which is a continuation of the 

 Spruce Hill Pass, there is exhibited a sandy plain of definite character at 

 1,300 to 1,340 feet in height. 



16 Woodworth : N, Y. State Mus. Bull., No. 84, p. 170, and pi. 21. 



