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N E W YORK STATE MUSEUM 



northwestward to the 720 foot line at Armstrong's bush are 

 believed to have been formed at this time. 



Gradually the waters at the outlet cleared out the main gorge 

 of the Hudson and finally came to a lower level with an outlet 

 just north of Fort Edward, establishing a level over the lake 

 about 100 feet low 7 er than that of the Coveville stage. At this 

 time the shore line stood somewhere near 550 feet at the 

 southern end of the Mooers quadrangle and at about 620 feet 

 at the northern end of the area. 



This glacial lake, which it is proposed to call Lake Vermont, 

 endured for some time longer when the ice sheet melted out along 

 the northern border of the Green mountains and allowed the 

 waters to fall to the level of the sea. On account of the then low 

 stand of the land the sea at once came in and spread as far south 

 as Whitehall. 



Before the sea came in, however, there appears to have been a 

 stage in which the lake w T aters gradually fell below the Fort 

 Edward outlet, presumably by reason of the weakening of the ice 

 barrier on the north allowing the more or less gradual escape of 

 the lake waters. The crowded beaches in the northern part of 

 the quadrangle from 540 feet down to the upper marine limit near 

 the 450 foot contour line are referred to this stage. I have 

 described their correlation with what appear to be stream-cut 

 terraces on the northern side of Covey hill in another paper on 

 the ancient wmter levels of the Hudson and Champlain valleys. 



It has been suggested by Mr Warren Upham that the ice front 

 receded from the Champlain valley in such a manner as to allow 

 a connection between the glacial lake in this field and one extend- 

 ing over the upper St Lawrence valley into Lake Ontario, previous 

 to the invasion of the district by the sea. These beaches and 

 possibly some of the lower ones referred to the marine stage would 

 be thus explained but not so the cut terraces at Covey hill and 

 the occurrence of marine shells on Mt Royal at an elevation of 

 about 550 feet. 1 



The average inclination of these old water levels to the south 

 is assumed to be parallel to the upper marine limit. An attempt 

 to trace some one line of beaches proved unavailing as a test of 



1 Sir William Dawson gives both 540 and 560 feet far the elevation. 



