LIME AND CEMENT INDUSTRIES 809 



layers in tlie same quarry, one perliaps containing only 2^, while 

 the others may have 16fo 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 IsTew Jersey. It possesses the same character as the 

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

 the railroad' between JSTeelytown 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 IRewburgh. 



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 ISTewburgh indicates the rather constant character of the stone. 

 It runs: 



Lime , , 27 . 75 



Magnesia 17 . 65 



