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NEW YORK STATE MUSEUM 



with huge boulders of hmestone. The cHff which Hmits Winter- 

 green flat on the northern or downstream side is the highest and 

 most precipitous, and from its base a weU marked, dry channel 

 leads northward for a third of a mile to the river's edge. This chan- 

 nel is separated from the present river channel on the right by a 

 ridge which appears to consist of huge limestone blocks, though its 

 base is probably formed by undisturbed remnants of the lower 

 strata of the region. The floor of this old channel is strewn with 

 huge limestone boulders, such as are found at the foot of the 

 American falls today, and its left bank is the precipitous west wall 

 of the Niagara gorge. (Fig. 17) 



Fig. 17 View of Niagara glen or Foster's flats, looking south. Forests omitted. (After Gilbert) 



These various features have been well explained by Mr Gilbert,^ 

 who holds that a narrow island comparable to Goat island, divided 

 the fall in two, when it had receded to the northern end of Fosters 

 flats. The foundations of this island, which has since crumbled 

 away, are seen in the ridge which divides the old dry channel on 

 the left from the main bed of the river. The eastern or American 

 fall at that time was the larger of the two, and it receded more 



^Nat. geog. monographs. Niagara falls and their history. 



