﻿Plate 31 



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Upper figure. Hand specimen of faulted Potsdam sandstone, nearly 

 natural size. The rock is red, with white streaks, and the fault plane is 

 filled with white, thoroughly cemented sand. 



Lower figure. Hand specimen of basal, Lowville conglomerate from 

 near Depauville (Clayton quadrangle). The pebbles of fine limestone 

 mud, of dove color, weather prominently white, as compared with the 

 remainder of the rock surface. H. P. Cushing, photo 



