LIME AND CEMENT INDUSTRIES 779 



Since dolomitic limestones tend rather to disintegrate than to 

 decompose, their outcrops are often surrounded by a white granu- 

 lar sand, and are easily discernible for some distance. The west- 

 ern belt has been quarried in large quantities at Clinton point 

 (pi. 35), 2 miles north of New Hamburg. Its silicious nature 

 restricts its use to road metal. 



An analysis of this stone gave: 



Lime . 29.07 



Magnesia 16 . 29 



Carbonic acid 40 . 76 



Alumina 2 . 33 



Ferric oxid 47 



Silica 10.17 



99.09 



Erie county * 



The only limestone formations represented in this county are 

 the hydraulic or waterlime, the Onondaga and the Corniferous. 



According to Bishop, " the northern edge of the Corniferous 

 limestone, together with the Onondaga limestone and the upper 

 part of the hydraulic limestone, forms a well denned escarpment, 

 which runs in a general southwest direction on the Genesee 

 county line to Buffalo. Most of this distance the escarpment is 

 nearly parallel to the Bloomingdale and TVilliamsville road. The 

 hydraulic limestone is generally visible at the base of the escarp- 

 ment, where it forms a layer of variable thickness in the face of 

 the cliff. Sometimes it forms a terrace from a few feet to 200 

 yards in width which runs parallel to the escarpment. This is 

 specially well marked between the Williamsville and Buffalo 



if Bishop, I. P. Structural and economic, geology of Erie county, {see loth 

 an. rep't X. Y. state geol. p. 305) 



Hall, James. Geol. 4th dist. N. Y. p. 4G9. 



Pohlman, J.' Cement rock and gypsum deposits in Buffalo, {see Trans. 

 Am. inst. min. eng. Oct. 1888) 



