GLACIAL WATERS IN BLACK AND MOHAWK VALLEYS 35 



a few of the highest, ranging above 1200 feet, probably represent the 

 Forestport level, while those from 1200 down to about 900 feet 

 belong to the Schoharie lake, which seems to have entered the basin 

 through the Steuben valley northwest of Trenton. Below 900 feet 

 the terraces must correlate with the Amsterdam waters, or below 

 830 feet (the Steuben col) with the local lake. 



The ice seems to have lingered on the southwest flanks of Quaker 

 and South hills while the Schoharie lake fell to the Amsterdam lake, 

 and then the Lansing kill river extended itself through the Steuben 

 valley. 



When the ice weakened on the flank of Quaker hill the ponded 

 waters of Fish creek and tributaries found their outflow through 

 the splendid series of strong channels west and east of Lee Center-; 

 and at the same time, the ice waning on the western slope of South 

 hill, the waters found their ultimate escape by channels at Delta, 

 Floyd and Marcy, at 600 to 500 feet, into Mohawk waters of late 

 Amsterdam stage. These features are shown in plate 2. 



As the Port Ley den lake (Copenhagen outlet, see page 13), 

 following the suppression of the Boonville river, was probably as 

 late as early Iroquois time, and as the initiation of Lake Iroquois 

 was in the Rome-Oneida district, it follows that the Lansing kill 

 and upper Mohawk valleys held glacial waters from at le-^st the 

 time of Forestport lake down to initiation of Iroquois. The ice 

 here made its most determined stand, at the head of the Mohawk 

 valley; and the consequent production of channels and deltas make 

 it the critical locality for correlation with similar effects of the 

 ice barrier at the east end of the Mohawk valley.. 



Of the many marginal lakes, mostly small, which the ice held on 

 the north and the south slopes of the Mohawk valley only one will 

 be described here, though a close study will discover many interest- 

 ing details of the history. 



Sacandaga lake. A large lake tributary to the Mohawk waters 

 was held in the Sacandaga and upper Hudson valleys. From its 

 sources in the southeastern Adirondacks this river enters a broad 

 valley at Northville and at Northampton turns northeast and joins 

 the Hudson at Luzerne. During all the time covered by this history 

 the Hudson drainage was blocked by the Hudsonian ice lobe and 

 the waters of all the Adirondacks were forced into tribute to the 

 Mohawk lakes. During the life of the Schoharie lake the ice lay 

 across the upper Hudson somewhere in the district of Corinth, 

 covering the area of Saratoga and Ballston, and the Schoharie 

 Vv^aters must have flooded the territory of Johnstown, Gloversville, 



