Niagara Falls 



1901 



Hitchcock 



1901 

 Letson 



1902 



Wright 



1903 



Clarke 



1903 



Upham 



of long duration. Nothing about Niagara gives us any clue to 

 the duration of the Labrador ice-sheet. The time of the wear- 

 ing of the whirlpool basin, 475 years, is not included in the 

 estimate of the age of the general gorge. 



Hitchcock, Charles H. Story of Niagara. (Am. antiq., Jan. 

 and Feb., 1901. 23:1-24.) 



LETSON, ELIZABETH J. Post-pliocene fossils of the Niagara river 

 gravels. (Bull, of the N. Y. state museum. No. 45. 9:238-252.) 



1902 



Wright, George Frederick. The rate of lateral erosion at 

 Niagara. (Am. geol., March, 1902. 29:140-143.) 



Definite results of observations made in 1 899 to determine the rate of 

 lateral erosion at Niagara. The investigations were undertaken at the 

 commission of the New York Central R. R. after the publication of the 

 author's article on " Lateral Erosion " in the Popular Science Monthly 

 for June, 1899. 



1903 



CLARKE, John M. Scientist's view of Niagara. (Harp, w., Nov. 

 21, 1903. 47 (part 2):1866.) 



The New York State Paleontologist foretells the death of Niagara 

 Falls from natural causes 3,500 years hence. He thinks that the escarp- 

 ment will be left dry " at a point not very far south of Goat Island with a 

 height of one hundred feet." 



Upham, Warren. The past and future of Niagara Falls. (Ann. 

 rep'ts of the com'rs of the state reserv. at Niagara. Albany: 1903. 

 19:229-254.) 



The greater part of this paper was first published in The American 

 Geologist for October, 1901, volume 28, pp. 235-244, to which were 

 added introductory paragraphs and the discussion of the future changes 

 of Niagara lakes. The author estimates the time required for the erosion 

 of the gorge as about 7,000 years, considerably less than the estimate of 

 many geologists who preceeded him. 



The chief interest of geologists in their studies of the Niagara 

 gorge and falls, which have been set forth in many essays, pub- 

 lished mostly within the last fifteen years, arises from the fact, 

 admitted by all, that the gorge erosion began at the end of the 



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