Niagara Falls 



1901 the geological world) , it seems very certain that thereafter Lake 

 Erie, Lake Huron and Lake Superior sent their waters to the 

 sea through an outlet which Lake Michigan then had into the 

 Mississippi. A barrier not greater than fifty feet in height would 

 suffice, even to-day, to reverse the current of Lake Erie and Lake 

 Huron and compel the discharge of their contents into the 

 Mississippi, either by reopening the old, abandoned channel at 

 the head of Lake Michigan or by forming a new one. The 

 barrier, which was broken down at the time, when in fact the 

 physical history of the Niagara River began, may be pointed 

 out with reasonable certainty to-day. A ridge near the foot of 

 Lake Erie, which at one time extended in an eastward and west- 

 ward course, crossing the present channel of the Niagara River, 

 was that barrier. On either side of the river it attains a height 

 of sixty or seventy feet above the present level of Lake Erie. 

 It is almost unnecessary to say that this barrier was of glacial 

 origin — an immense moraine. From its base, on the northerly 

 side, to the verge of the cliff at Lewiston and Queenston, where 

 the cataract began its work of erosion, the surface of the under- 

 lying rock rises steadily. At the summit of the cliff at Lewiston 

 and Queenston, it has an elevation of thirty-two feet above the 

 present level of Lake Erie. 



It is fair to assume that although the lake (or river) , after its 

 irruption through this barrier, spread widely, yet that the begin- 

 ning of the excavation of the chasm at Lewiston was not long 

 delayed. 



Along the entire length of the river from Lake Erie to Lewis- 

 ton and Queenston, the terraces left by the river, as from time 

 to time it deepened and narrowed its channel, may be easily 

 recognized. Often they show evidence that they were formed 

 at the bottom of the river before the chasm had been excavated, 

 being very largely composed of water-worn stones and materials, 

 brought and deposited by the river itself from more southerly 

 localities. 



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