Science, Geology and Physics 



of the lapse of time necessary to accomplish all this. But the 1850 

 greatness of the lapse is felt when we see before us the pro- J°^ n8ton 

 tracted effect, and the still living and acting cause. The foam 

 of the cataract becomes, to the imagination, the hoary hair of 

 thousands of years, and its perpetual rainbow a halo round the 

 head of the sleepless spirit which has seen these changes and 

 survived them all. 



The fresh-water shells which occur in the deep bed of mixed 

 slaty gravel and red clay drift, which covers the limestone rocks 

 at the edge of the waterfall upon Goat Island, are now well 

 known. The minute, almost microscopic species, I found very 

 abundant in the clay. Besides the shells usually collected, I 

 picked up a fragment of a fresh-water crustacean. 



1851 



Smith, William Henry. Canada: past; present and future; being i 85i 

 a historical, geographical, geological and statistical account of Canada Smith 

 west. Toronto: (1851.) 1:198-204. 



A short account by one evidently familiar with the literature of the 

 subject and particularly interested in the geology of the Falls. 



1853 



DESOR, E . (Ueber Niagara Falls.) (Geologische gesell- 1853 



schaft. Seitschrift. Sept. 1853. Ed. 5. Pp. 643-644.) (Abstract.) Desor 



This paper deals with the recession of the Falls, which the author esti- 

 mates to be less than it is estimated by either Bakewell or Lyell. 



1854 



Variations in the level of the lakes. (Can. jour., Jan. 1854. 2:129.) 1854 

 Gives the volume of the Falls as estimated by Barrett at Black Rock. 



1855 



Desor, E. The falls of Niagara and their retrograde movement. 1855 

 tr. by J. D. Meredith. (Pottsville scientific association. Potts- Desor 

 ville, Penn.: Bulletin, Jan. & Feb. 1855. Pp. 5-10.) 



565 



