Niagara Falls 



1908 Spencer, Joseph William Winthrop. Side issues bearing on 



Spencer the age of Niagara Falls. (Sci., Nov. 27, 1908. 28(n. s.) :754- 



759.) 



Spencer's answer to Gilbert's review of Spencer's " Evolution of Niagara 

 Falls" in Science, July 31, 1908. 



Spencer, Joseph William Winthrop. Soundings in Niagara 

 gorge and under the falls. (Sci. Am., Aug. 1, 1908. 99:76-77.) 



The results obtained were made by the special application of sounding 

 methods " to determine what work the Falls of Niagara had accomplished 

 at each point in their recession." 



These results show that the narrow channel was formed when 

 the level of Lake Ontario was about 180 feet lower than now, 

 at the time when the Niagara was draining only the Erie basin 

 and not the four upper Great Lakes. They show that the Falls 

 were once very much higher than now, and that the last cataract 

 of the three which composed them was alone over 300 feet high, 

 and the whole aggregated over 500 feet. 



The soundings also complete the proof that the Falls were 

 located just above Foster Flats, or about three miles within the 

 end of the gorge, when the volume of the Niagara was vastly 

 augmented, owing to the addition of the waters from the three 

 highest lakes, which now took place. Again the soundings at 

 the Falls bring to light the fact that the modern cataract is not 

 so high as it was a few hundred years ago, before the completion 

 of the Whirlpool Rapids. 



Spencer, Joseph William Winthrop. Soundings under Niagara 

 Falls and in the gorge. (Science n. s., April 10, 1908. 27:587-589.) 



A resume of a paper read at the Philosophical Society of Washington, 

 March 1 4, 1 908. It gives a description of the application of sounding 

 methods to an unusual subject, by which the physical features of the gorge 

 were brought to light, thus determining what work the Falls of Niagara 

 had accomplished at each point in their recession. " The soundings also 

 complete the proof that the falls were located just above Foster Flats, or 

 about three miles within the end of the gorge, when the volume of the 



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