THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES.] 



Art. I. — The Submarine Great Canyon of the Hudson River ; 

 by J. W. Spencer, A.M., Ph.D.* 



Contents : 

 An Account of what has been done before this date. 

 The Hudsonian Canyon. 

 Surface Channels of the Continental shelf, and the Deep one of the 



Connecticut. 

 Constitution of the Continental shelf. 

 Origin of the Canyon. 



The Magnitude and the Time of the Great Elevation. 

 Summary and Conclusions. 



An Account of what has been done before this date. 

 The early work of the Coast Survey brought to light a 

 depression extending from near New York to the border of 

 the Continental shelf. Prof. J. D. Dana was the first to recog- 

 nize this feature as the submerged channel of the Hudson 

 River, formed when the continent stood at a greater altitude 

 above the sea than it does now. So much importance did he 

 attach to it, as evidence of terrestrial oscillations, that a map of 

 it appeared in all the editions of his Manual of Geology, since 

 1863, but only in the latest edition (1895) was it shown to 

 reach to a greater depth than 720 feet. In the last revision 

 the upper channel and the canyon sections are distinguished, 

 the latter to a depth of over 2000 feet. But the discovery of 

 the canyon was first announced by Prof. A. Lindenkohl in 

 1885f and further discussed in 18914 He found that it 

 reached to a depth of 2844 feet where the adjacent continental 

 shelf was submerged to only 420 feet — a gorge of 2400 feet in 



* This paper will simultaneously appear in the Geographical Journal of 

 London. 



f This Journal (3), vol. xxix, pp. 475-480, 1885. 

 | lb., vol. xli, pp. 489-499, 1891. 



Am. Jour. Sci. — Fourth Series, Yol. XIX, No. 109.— January, 1905. 



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