AMERICAN GEOLOGY DECADE OF 1840-1849. 



385 



survey until 186! 

 p. 540). During 



when he resigned, to be succeeded by Selwyn (sec 

 this period he submitted sixteen reports, dealing- 

 main ly with stratigraphic and 



Issachar Cozzens's 

 Geology of New 

 York, 1843. 



;% 



economic subjects, and in 1863 

 a summation of his results un- 

 der the caption of The Geology 

 of Canada (p. 517). 



Among the earl} T members of 

 the New York Lyceum was one 

 Issachar Cozzens, a chemist and 

 geologist, who has left as his 

 main claim to recognition here 

 an octavo volume of 111 pages 

 and 9 plates, entitled A Geo- 

 logical History 

 of Manhattan 

 or New York 

 Island, together with a map of 

 the Island and a suite of Sec- 

 tions, Tables, and Columns for 

 the Study of Geology, particu- 

 larly adapted to the American 

 Student. This was published 

 in 1843. The map and sections 

 were all hand-colored, the latter 

 somewhat gorgeously, and in- 

 cluded, aside from those relat- 

 ing to New York Island proper, 

 sections of Staten Island; one 

 across the Palisades on the west 

 side of the Hudson River; one 

 from Stony Point, on the Hud- 

 son River, through Dunderberg 

 Mountain in New York; one 

 from Brenton Reef to Ports- 

 mouth, Rhode Island, and one of 

 Niagara Falls, the latter show- 

 ing the origin of the falls 

 through the gradual undermin- 

 ing of the softer shales and the 

 breaking down of the harder 

 limestones above. 



The rocks of Manhattan Island proper were classed as (1) granite, 

 (2) syenite, (3) gneiss, (4) hornblende slate, (5) quartz rock, (6) serpen- 

 tine, (7) primitive limestone, and (8) diluvion, 

 nat mus 1904 25 



%, 



