292 THE AMERICAN MONTHLY [Oct 



was seen to be igneous, and melted by volcanic heat, then 

 cooled to rock. Fossils, (organic remains) were not look- 

 ed for. 



I have studied the rocks of the Palisades, which come 

 up on the right bank of the Hudson river. They appear 

 as a perpendicular crest two hundred feet high and make 

 a very striking feature to the accompanying scene when 

 viewed from vessels on the river. This ridge runs from 

 below Stoney Point, N. Y., to a point near Jersey City, 

 N. J. Farther south, it appears again on Staten Island 

 (where the Rahway river empties) and disappears. This 

 forms a first range of mountains. The second range is 

 the Wahchung or Orange mountains. The third range is 

 parallel to it but has not assumed a local name. They ap- 

 pear to be of the same rock notwithstanding. 



The Palisades are known to be intrusive ^raps, that is 

 to say were thrust into the Newark sandstone. The 

 others are extrusive, being poured out UPON the Newark 

 sandstone. They were both forced up from below in a 

 melted state and I doubt their being formed in the same 

 period as the Newark sandstone. 



In boyhood I went with Charles M. Wheatly for min- 

 erals to where they were driving the old Harlem Rail- 

 road tunnel through the granite and the Erie Railroad 

 through the Palisades. Besides gathering minerals I saw 

 the trap rock in the Palisades was polished and grooved 

 by ice most likely, and the grooves came from the north- 

 west. The volcano trap was marked by big haxagonal 

 crystals often more than three or four feet across and 

 stood up perpendicular. This can be seen on the Hudson 

 River, and better still at O'Rourke's quarry in Orange, 

 N. J. On the side of the gray trap ridge is the green 

 serpentine as seen at the old Elysian Fields and on the 

 west side is the red Newark sandstone. Then 1 went to 

 dwell upon the red sandstone, the Juro-triassic of Dana, 

 f he Newark of Russell. I was near the trap and could 



