yo NEW YORK STATE MUSEUM 



Other conspicuous drainage changes have taken place in the 

 heart of the Adirondacks. Before the Ice Age the basins 

 now occupied by Blue Mountain and Eagle lakes quite cer- 

 tainly drained eastward into the Hudson river by way of Rock river 

 instead of westward as at present through Raquette lake and thence 

 northward into the St Lawrence. Evidence in support of this view 

 is twofold, namely, the rock barrier at the western end of Utowana 

 lake and the loose glacial debris dam at the eastern end of Blue 

 Mountain lake. Loose material only separates Utowana and Eagle 

 lakes. Thirty-four marsh and Rock river come to within a half 

 mile of Blue Mountain lake and they are about 20 feet lower than 

 the lake surface, the intervening space being occupied by loose sands 

 and gravels. It would be a simple matter, by shoveling out a trench 

 not over 20 feet deep, to cause Blue Mountain and Eagle lakes to 

 drain eastward. Years ago such an attempt was made but stopped 

 by law. Thus the movement of water here must have been eastward 

 in preglacial time. 



That the preglacial drainage through the Utowana lake basin 

 passed westward into the basin now occupied by Raquette lake is 

 certain, there being only loose material across the western end of 

 Utowana lake. From the Raquette lake basin the preglacial drain- 

 age was almost certainly southwestward by way of the valleys now 

 occupied by the Fulton chain of lakes. A maximum thickness of 

 less than 100 feet of glacial deposits just north of Eighth lake is 

 all that is necessary to account for the blockade of the southwesterly 

 preglacial channel with resultant ponding of the waters to form 

 Raquette lake. Further evidence for the southwestward course lies 

 in the fact that between Forked lake and Long lake, Raquette river 

 descends more than 100 feet in about 3 miles, mostly by a series of 

 cascades over rock ledges which extend across the narrow channel. 

 Apparently a preglacial divide was situated not far below what 

 is now the outlet of Forked lake, the drift deposits southwest of 

 Raquette lake being sufficient to cause the ponded waters of Raquette 

 and Forked lakes to overflow this divide. 



The depression now occupied by Long lake was certainly a pre- 

 glacial stream channel, and there is also strong evidence that the 

 drainage from this channel passed eastward into the Hudson river 

 rather than northward by way of Raquette river and into the St 

 Lawrence as at present. At Raquette falls, on the river a few miles 

 below the outlet of Long lake, there was a divide with a north- 

 flowing and a south-flowing stream from it. Thus, in preglacial 

 time two streams drained into the depression now occupied by Long 



