ANCIENT WATER LEVELS OP CH A MPLAIN— HUDSON VALLEYS 111 



Peekskill. These clays are probably an extension of the eroded 

 ancient clays seen at Crugers. 



Low lercl terraces. Again in this vicinity there are to be seen 

 small areas of sandy plains stretching between rock outcrops in 

 the dissected margin of the river gorge. One of these plains is 

 well developed about the east shore of Lents cove, from a mile to 

 a mile and a half south of Peekskill, with a surface about 20 

 feet above the sea. Another small deposit at about this level 

 connects Roa Hook with the remnant of a rock terrace on the 

 northwest of it. There is required much more evidence as to the 

 nature of the original margins of these deposits on the river side 

 before it can be asserted that they were or were not deposited in 

 the presence of ice remaining in the gorge. They are evidently 

 later than the high level terraces which overlook them. 



Terraces about West Point and Cold Spring [see pi. 3, West 

 Point quadrangle]. The topographic features of the Hudson at 

 Peekskill are partly duplicated between 8 and 9 miles upstream 

 within the Highlands in the vicinity of West Point. In this 

 bend of the river, West Point with its terrace, takes the place of 

 Jones Point, and Cold Spring on the delta of Foundry brook that 

 of Peekskill. The ancient rock terrace of the Hudson partly 

 masked by glacial deposits both at West Point and Cold Spring 

 somewhat complicates the problem and gives the glacial deposits 

 the appearance of a greater development than they really 

 possess. It is interesting to note that Constitution island, a 

 rocky mass in the middle of the gorge, is practically free oi 

 glacial deposits, for reasons which it is believed will appear w T hen 

 the bordering terraces have been discussed. 



The West Point glacial terrace rises from 160 to 180 feet above- 

 the sea. The original character of the deposit is best shown, 

 north of the West Shore Railroad tunnel from the site of the 

 cemetery to the weak morainal deposits at the base of Crow's 

 Nest mountain. The upper deposits in this portion of the ter- 

 race are coarse cobbles becoming coarser and the deposit really 

 bouldery near the base of the mountain named with a kettle 

 moraine topography of weak relief. The railroad cuts north of 

 the tunnel expose gravels quite to the river level showing that 

 the deposit here is a true glacial terrace and not merely a coat- 

 ing of the ancient rock terrace as is the case near the parade 



