256 BULLETIN OF THE NEW YORK STATE MUSEUM 



retaining-walls, and where it can be used without much cut- 

 ting or dressing. 



Port Henry, Essex County. — The outcrops of the Potsdam 

 sandstone in the town and west of it afford quarrying sites. 

 The quarry of L. W. Bond is worked for the local market, 

 and the towns on the line of Delaware and Hudson Canal 

 Company's railroad in the Champlain valley. The stone is 

 hard, of a gray shade, excepting the surface beds, which are 

 weathered to a rusty-red c^lor. It is nearly all silica, and 

 is capable of resisting the ordinary atmospheric agents for 

 years, when the blocks are laid on their bedding planes. A 

 serious drawback to its more extensive use is the cost of 

 cutting and dressing. 



Examples of this stone in construction are seen in the 

 Presbyterian church, and in the Sherman Library building, 

 and the railroad depot in the town."^ 



Keeseville. — The Ausable river, the boundary line of Essex 

 and Clinton counties, has at this place, and at the famous 

 chasm below the village, worn its bed down deeply into the 

 sandstone, and along its banks quarries have been opened 

 in both counties for local supply. 



The thin beds make a fairly good flagging-stone. The 

 heavier beds yield good stone for ordinary wall work ; and 

 a great amount of it has been put into buildings in Keese- 

 ville. In color it is gray-white. It is rather more granular 

 and not as hard as the Port Henry sandstone. 



Malone, Franklin County. — The sandstone of the Potsdam 

 horizon is opened by small quarries at this point, and at lo- 

 calities to the west, but they are unimportant, and the next 

 group to be noted is at 



Potsdam, St. Lawrence County. — The formation is so well 

 developed in the valley of the Raquette river, south-east of 

 the village of Potsdam, that it has been named the Potsdam 

 sandstone. 



* This quarry yielded the trails of trilobites upon ripple-marked beds, fine speci- 

 mens of which are in the State Museum, and the American Museum, New York. 

 (See Forty-second Annual Report, New York State Museum, pp. 25-29.) 



