810 Is^EW YOEK STATE MUSEUM 



Carbonic acid 40 . 99 



Alumina 1.93 



Ferric oxid , 1.8 



Silica ,. 10.46 



100.58 



This stone is used to a small degree for lime-maldng. 



Wliile swampy tracts are abundant in Orange county, the 

 writer has not been able to prove the existence of marl under any 

 of them. 



The Lower Helderberg limestones, though known to occur 

 along Schunemunk mountain in the eastern part of Orange 

 county, are not important there, but do form a prominent strip 

 along the western side of Shawangunk mountain. The Pen- 

 tamerus is exposed in a quarry about 4 miles southwest of Otis- 

 ville and was at one time burned for lime (pi. 59). A much bet- 

 ter section is exposed in Bennett's quarry east of Port Jervis, 

 and adjoining the road to Middletown at a point about 1 mile 

 east of TriStates. This stone would be available for Portland 

 cement manufacture. 



The Corniferous or Upper Helderberg forms a low ridge east 

 of Port Jervis, and also underlies TriStates point. It is full of 

 chert nodules. 



Orleans county^ 



This county, like several of the others bordering on Lake 

 Ontario, contains a broad band of the I^iagara limestones. The 

 material utilized in every case for the manufacture of lime is the 

 upper member. Quarries are in operation at Barre Center, south 

 of Albion, (pi. 60) Clarendon and Shelby. 



At the first named locality, the material used is chiefly disinte- 

 grated surface blocks. At this point one of the quarrymen, 

 B. Johnson, recognizes three types of stone, viz, the porous, or 



iHall, James. Geol. 4th dist. N. Y. p. 433. 



