GEOLOGICAL POSITION AND GEOGRAPHICAL DISTRIBUTION 219 



It Is recognized In the Bellevale and Skunnemunk moun- 

 tains, also In Orange county. In the central part of the 

 state It Is traced westward In a narrow belt from Herkimer 

 county Into Oneida county. The prevailing rocks are gray 

 and reddish-gray, siliceous conglomerates and sandstones, 

 which are noted for their hardness and durability. The 

 cementing material Is siliceous. The jagged edges and 

 angular blocks and the polished and grooved surfaces of 

 the glaciated ledges, so common on the Shawangunk range, 

 afford the best proof of the durable nature of these rocks. 

 The bottom beds, near the slate, contain some pyrlte. No 

 attempt has been made to open quarries for stone, excepting 

 at a few localities for occasional use In common wall work. 

 The grit rock was formerly quarried near the Esopus creek 

 In Ulster county for millstones.^'* 



The accessibility of the outcrops to the New York, Lake 

 Erie and Western R. R., the N. Y., Ontario & Western R. 

 R., the West Shore R. R., and the Del. & Hud. Canal lines 

 Is an advantage, as well as the comparative nearness to New 

 York. And no other formation in the state exhibits in Its 

 outcrops better evidence of ability to resist weathering 

 agents. 



Medina Sandstone 



The Medina sandstone Is next above the Oneida conglom- 

 erate. It is recognized in the red and gray sandstones 

 and the red and mottled (red and green) shales of the 

 Shawangunk and Skunnemunk mountains in Orange county. 

 A large amount of the red sandstone has been quarried on 

 the north end of the Skunnemunk range, In the town of 

 Cornwall, for bridge work on the railroads which cross the 

 range near the quarry. 



The red sandstone is seen exposed in the cuts of the Erie 

 Railway northeast of Port Jervls. This formation reappears 

 in Oswego county, and thence west to the Niagara river In 

 a belt bordering Lake Ontario. 



*Wm. W. Mather. Geology of the First Geological District, Albany, 1843, p. 357. 



