NE-SAW-JE-WON 



New York, outlet of Lake Iroquois and caused the water to 

 be ponded back on the southern shores, but it was not high 

 enough to cause a reversal of flow back into Lake Erie. At 

 this stage Lake Iroquois made its strongest beach. 



More Work of Niagara River 



The early increase in volume in the rejuvenated Lake Erie 

 increased the activity of Niagara River: a greater volume of 

 water flowed over the falls, and a wider gorge was cut — that 

 part of the gorge extending from the bend north of Niagara 

 University up-stream as far as the head of Foster Rapids. 

 When the Chicago outlet was abandoned and all the water 

 of the upper lakes poured over Niagara, the wide gorge from 

 the head of Foster Rapids to the upper edge of the Eddy 

 Basin above the Whirlpool was made. Together these parts 

 of the gorge are known as the Lower Great Gorge. (Figure 

 12.) Curiously, the Whirlpool is not a part of the gorge 

 proper. Its story is actually older than that of the gorge in 

 which it now lies. At some time before the last ice invasion, 

 a river flowing from southeast to northwest had plunged over 

 the Niagaran escarpment at the site of the little Canadian 

 town of St. David. Like the Niagara, this river, which has 

 been named St. David, cut a gorge back from the escarpment 

 as far as the Eddy Basin just above the Whirlpool. The on- 

 coming glacier destroyed the river and filled its gorge with 

 rock debris (drift) , which then became considerably cement- 

 ed together although not as solid as rock. Later, when the 

 Niagara had cut back to the old buried gorge, the northeast 

 wall of the gorge supporting the falls became thin and 

 crumbled, giving the waters access to the less-resistant ma- 

 terial filling the old channel. The waters of Niagara, plunging 

 with great force and volume, soon scoured away the glacial 

 debris, swirled and hurled its heavy tools northwest into the 

 buried gorge until it had made the Whirlpool. The depth of 

 the Whirlpool is due in part to the depth of the buried gorge 



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