wAuoiT.] NIAGARA FALLS TO NEW YORK CITY. 463 



the crystalline schists of the Highlands occupy the western shore until 

 the trap ridge of the Palisades is encountered. At Weehawken the 

 characters of the trap are finely shown in the quarries. 



The drift features, from Niagara Falls to Schenectady, include at first 

 ground moraine with undulating surface, and afterward, between Roch- 

 ester and Syracuse, a tract of drumlins of the more elongated type. 

 At Little Falls the Mohawk River appears to have cut a postglacial 

 channel, and tine river terraces occur above the gorge through which 

 the river passes. Below the falls the river silt and gravels nearly till 

 the valley from side to side. 



The most important Pleistocene deposit of the Hudson Valley is a 

 great bed of laminated clay referred to the Champlain epoch and 

 known locally as the Albany clay. It is the sedimentary record of a large 

 estuary occupying the Hudson Valley after its abandonment by the 

 ice, and it appears originally to have stretched from side to side of the 

 valley, filling the river channel and masking the rugosity of the base- 

 level plain. Xear Schenectady its upper surface bears a heavy layer 

 of sand. After its deposition the land rose temporarily to a height 

 greater than the present, permitting the river to carve its channel to 

 such depth that it has not since been refilled with alluvium. The 

 so-called river is still an estuary for 150 miles (2-40 km.) from its mouth, 

 transmitting ocean tides as far as Albany. 



From the terminus of the West Shore Railway at Weehawken trav- 

 elers are transferred to New York City by terry. 



