Science, Geology and Physics 



The earliest discussions of the recession of the falls led to 1903 

 apprehension of danger and disaster, because the continuance u P ham 

 of the present gorge erosion must eventually extend to Lake Erie, 

 the reservoir whence the river flows. It was thought, therefore, 

 in the excited imagination of many ignorant readers, when the 

 early geological discussions of the history of Niagara were pub- 

 lished, that a destructive flood would thus be let loose from Erie 

 and the upper lakes to deluge the Ontario basin and the St. 

 Lawrence valley. Professor James Hall, in 1843, endeavored 

 to allay these fears. The increasing southward dip of the rock 

 strata between the present falls and Lake Erie will cause the 

 Niagara to cut into softer and easily eroded beds along that 

 distance, so that its great cataract, which depends on the thick 

 and hard Niagara limestone overlying soft shale, can be no 

 longer maintained. The river will then run, as Hall declared, 

 in a series of rapids along all its course from Lake Erie to Lewis- 

 ton, with perhaps a low fall at the outlet of the lake. He fur- 

 ther wrote : ' The views which have been entertained of the 

 sudden drainage of this or any of the upper lakes, and a deluging 

 of the country on the north and east, are no longer considered as 

 tenable by any one; and even if Lake Erie could be drained 

 suddenly, it would cause no deluge of any importance." 



More recently another anxiety has been raised by computa- 

 tions of a probable tilting of the land, slightly changing its incli- 

 nation on all the region of these great lakes, so that ultimately 

 the mouth of Lake Erie would be lifted higher than the very low 

 water divide close southwest of Chicago. The Niagara cataract 

 would then be left dry, and the outflow of all the lake basins 

 above Ontario would pass, as during the existence of the glacial 

 Lake Warren, to the Des Plaines, Illinois, and Mississippi rivers. 

 Spencer, in 1 894, computed that the land tilting will thus divert 

 the drainage about 5,000 or 6,000 years hence, and that this 

 will take place before the gorge erosion will reach Lake Erie. 



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