242 m:\\ V(»i:k statk museum 



but south of (his latter naiiKHl point tliore is no trace of deposits 

 so ]i\\v as (his stage in the glacial retreat now recognizable above 

 the sum HI it line of the walls of the Hudson gorge. It is to be 

 inferred therefore that Lake Albany had its southern limit some- 

 where in the vicinity of Khinebeck and Koudout and that south 

 of iliat point the surface of the rock terraces wei'e then and have 

 ever since been aibove the level of stiinding water. 



The shore lines of Lake Albany, determined by the hight of 

 marginal deltas, now rise to the north at a somewhat steeper 

 rate then the land on the south of the Highlands, but from New- 

 burg northward for several miles there is great discrepancy in 

 the level of deltas marginal to the gorge, some of the terraced 

 deposits being of a character and elevation to suggest that the 

 water level varied greatly from time to time. On the whole the 

 deltas from Kondout northward to Albany appear to lie in a 

 tilted plane which, if continued southward, passes below that in 

 which the deltas from the Highlands southward lie. This is 

 interpreted to mean that, as time went on, the detritus in the 

 loAver Hudson gorge and about its mouth, in and about the 

 terminal moraine, was swept aAvay by powerful currents loAver- 

 ing the level of the waters about the ice margin. This of course 

 could only take place if the land were far enough above sea level 

 to render the water levels in the Hudson valley- independent of 

 the control which would be exerted by a submergence in the sea. 

 The facts seem to indicate that the land Avas so far tilted down 

 on the north and up on the south that Lake Albany, held in by 

 the ice front on the north, was caused to spread over the rock 

 terraces in the uj^per Hudson valley while an outlet for its waters 

 was found through the gorge on the south of Khinebeck below that 

 at which the sea stands today. 



For a time the wat(M*s of Lake Albany extended northward over 

 the Fort lOdward disliict, covering the lower ])ortion of the 

 j)lateau alH)ut Fort Ann; and thence, connecting through the 

 narrow defile of ^^'()od creek, united with a glacial lake Avhich was 

 extending northward in the valley of Lake (Miamplain ])ari passu 

 w illi the retreat of the ice from that valley. Tlu^ attitude of the 

 hiiid fi'oiii l.aket 'hanij)lain souf liward to the ivgion of Lake Albany 

 was now Ilia I of depression on the north so that the floor of Lake 



