FOURTH REPORT OF THE DIRECTOR I907 65 



of glacial geography. The marine and glacial shore lines were 

 visited on the route westward from Mooers, and the party stopped 

 for lunch in *' The Gulf," near the two lakes which show the location 

 of the gorge that represents the ancestor of Niagara. The noon 

 talk, given by J. B, Woodworth, who has worked out the glacial 

 history of this region, was on 



Abandoned shore lines 



At " The Gulf " Professor Woodworth spoke in substance as fol- 

 lows : " The Gulf " and Covey hill north of it constitute a locality 

 of critical importance in the study of water levels in the Champlain 

 and St Lawrence valleys. " The Gulf " pertains to the closing 

 stages of the great ice-dammed lakes which formed in front of the 

 ice in its retreat from the territory of the United States. When 

 *'' The Gulf " was being excavated by a powerful torrent of water, 

 the ice sheet still hugged the northern side of Covey hill, itself the 

 northermost spur of the Adirondacks. 



The waters which entered " The Gulf " came from the west, the 

 region of Lake Iroquois, whose waters would have taken this path 

 after the ice retreat offered a lower outlet than that at Rome. The 

 waters passed from " The Gulf " into Lake Vermont, the preglacial 

 lake occupying the valley of the present Lake Champlain. Lake 

 Vermont could not at this stage of its existence have risen above 

 the surface of the water in the waterfall pools of " The Gulf." The 

 lower lake is now 645 feet above sea level. Tlie sea could not at 

 this latitude have stood higher than the bottom of " The Gulf." 



With the further retreat of the ice from the northern slope of 

 Covey hill the water, which had previously discharged through 

 *' The Gulf " on the south side of the hill, flowed around the north- 

 ern slope of the hill and emptied into the sea. The salt water came 

 in, and the history of the great glacial lake was completed. 



Signs of wave action occur on the Champlain side of the Adiron- 

 dacks as high as 720 feet, but these higher water levels do not 

 continue about the northern side of Covey hill north of '' The Gulf." 

 A good beach is continuous from the Champlain valley about Covey 

 hill into the upper St Lawrence valley with an altitude of 450 feet 

 at Covey hill. Higher signs of probable wave action occur up to 

 570 feet, merging into beaches evidently made by torrential waters 

 confined between the hillside and the retreating ice front. 



" The Gulf " was properly understood by Ebenezer Emmons to 

 have been made by a powerful torrent flowing where now no stream 



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