LIME AND CEMENT INDUSTKIES 809 



layers in the same quarry, one perhaps containing only 2$, while 

 the others may have 15$ or 18$. 



An area of white limestone extends from Florida through Pine 

 Island and Amity into New Jersey. This is a highly crystalline, 

 metamorphosed limestone, which also occurs in a broad belt that 

 extends southwest from Florida through Big Island and Gardiner- 

 ville into New Jersey. It possesses the same character as the 

 other belt. A small area of Trenton limestone is found along 

 the railroad between Neelytown and Campbell Hall. This has 

 been used to a small extent for lime. The Cambro-Silurian 

 limestones also outcrop both southwest, west and north of the 

 city of Newburgh. 



The character of these Cambro-Silurian rocks of the Orange 

 and Rockland county belt may be judged from the following 

 analyses made of samples collected from different parts of the 

 quarry, the analyses in each case representing the average of the 

 quarry. 



The first one of the magnesian limestone from Tompkins Cove, 

 (pi. 58) is as follows: 



Lime 26.34 



Magnesia , 16 . 74 



Carbonic acid 39.1 



Alumina , 4.13 



Ferric oxid 1.05 



Silica , 12 



99.36 



This analysis shows that the stone is both magnesian and 

 highly silicious. The following analysis of the Cambro-Silurian 

 limestone from Miller Bros.' quarry on the southwestern edge 

 of Newburgh indicates the rather constant character of the stone. 

 It runs: 



Lime 27.75 



Magnesia 17 . 65 



