Science, Geology and Physics 



1907 



CORNISH, VauGHAN. The travels of Ellen Cornish: being the memoir 1907 

 of a pilgrim of science, with sixty-five plates from photographs by the Cornish 

 author, maps and plans. Lond. : W. J. Ham-Smith. 1913. Pp. 1 05- 

 138.) 



The author and his wife spent three weeks at Niagara in 1907. In the 

 account of their visit, there is given a full and complete description of the 

 Falls from all points of view with special attention paid to the physical 

 phenomena of the cataract, viz: the channel, its depth, width, etc., and 

 the formation of the whirlpool and lower rapids. There is a description 

 of the " standing waves " above the cataract, as well as of the steady and 

 continuous motion of the water at the foot of the fall. There is a reference 

 to Captain Basil Hall's theory of the effect of surface friction of the air 

 on these masses of water. An account is given of the trip on the Maid 

 of the Mist. In the description of the rapids and gorge close attention is 

 given to all details of the water effects, the color, formation, currents, etc. 



G. A. G. C. Erosion at Niagara; [Review of Gilbert's "Recession 1907 

 of Niagara Falls " and Report of Carvel Hall in Bull. U. S. geol. surv. G. A. G. C. 

 No. 306. 1907.] (Nature. 1907. 75:607.) 



GILBERT, Grove Karl. Rate of recession of Niagara Falls. 1907 

 Accompanied by a Report of survey of crest line of Niagara Falls, by Gilbert 

 W. Carvel Hall. U. S. Geol. survey, Bull. 306. 1907. (Ann. 

 rep'ts of the com'rs of the state reserv. at Niagara. Albany: J. B. Lyon. 

 1907. 23:39-73.) 



A discussion of data for estimating recession and the reasons for dis- 

 crepancy among the various data. Contains maps, views and diagrams. 



Introduction. 



The erosive work of the cataract of Niagara is exceptionally 

 rapid. This depends primarily on the great power of the falling 

 water, but in part on the character of the local geologic structure. 

 The rocks are stratified and lie nearly level. The upper layers 

 are of limestone, strong and resistant ; the lower, consisting chiefly 

 of shale, are comparatively weak and yielding. As the shales 

 are worn away below the limestone beds are undermined, so 

 that their edges project like a cornice and are deprived of 

 support. From time to time they yield to the force of their own 



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