Science, Geology and Physics 



Chapter 20, on the " Date of the Glacial Period," discusses the Niagara 1911 

 River at some length and in an interesting manner. In other parts of the wnghl 

 book there is also material on the geology of the Great Lakes region. 



1912 



Ontario-New York. Topographic map of the Niagara gorge. (U. S. 1912 

 geol. surv., G. O. Smith, Dir. and Geol. surv. of Can., R. W. Brock, 

 Dir. 1913. 1:12,000.) 



"(Admirable large scale map of the whole Niagara gorge from above 

 Niagara Falls to below Lewiston. The Falls themselves, the rapids above 

 and the Whirlpool Rapids below are graphically rendered by means of 

 hachures and fine lines in blue to represent eddies, supplemented by white 

 areas in the general blue tint for water to represent foam and spray. The 

 other elements are represented in the usual manner of the survey topographic 

 sheets; but here again due to the large scale, the delineation of city areas 

 (Niagara Falls, N. Y., and Ont., are both shown on the map) is especially 

 valuable.)" This survey was made in 1912. 



43° 11.0'; 43° 3.5' N; 79° 5.5'— 79° 1.8'W. Interval 10 feet. 



1913 



Notice of map of Niagara gorge. (Am. Geog. Soc. N. Y. Bull. 1913 

 45:849. Nov. 1913.) 



"A map of the Niagara River (1:12,000) from Lewiston to the 

 mouth of the Welland River has heen issued by the United States 

 Geological Survey to accompany the recently published Niagara folio. 

 This map was surveyed in co-operation by the United States and Canadian 

 Geological Surveys. It was compiled originally to accompany Guide Book 

 No. 4, entitled ' Excursions in south-western Ontario,' prepared by the 

 Executive Committee of the Twelfth International Geological Congress." 



Spencer, Joseph William Winthrop. Outline of the evolution 1913 



of the Falls of Niagara; contrast with the falls of Zambesi; . . .Spencer 

 Wash.: Press of Judd and Detweiler, inc. 1913. 



This brief paper which was written for the " International Geological 

 Congress," after discussing nature's work at the Falls says. . . . "In 

 the future the Falls are destined to be destroyed by man." 



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