LIME AND CEMENT INDUSTRIES 833 



One of the most accessible localities in Westchester county is 

 Yerplanck, where a large quarry of these pre-Cambrian limestones 



exists. 



Yates county 1 



No beds of limestone of importance are known in this county, 

 but marl may be found perhaps at the northern extremities of 

 Crooked lake. 



THE CEMENT INDUSTKY IN NEW YORK STATE 



Two types of cement are made in New York, viz Rosendale, or 

 natural rock cement, and Portland cement. 



The former industry was the earlier established, but the latter 

 is expanding rapidly. 



Natural rock cement 



The geologic position of the cement beds and their occur- 

 rence has been mentioned under " Geology of New York lime- 

 stones ", and in the descriptions of Ulster, Onondaga and Erie 

 counties, specially, and the statistics have also been given. It, 

 therefore, remains to give a brief description of the technology 

 of the industry as carried out in this state. The general process 

 of manufacture of natural rock cement has already been referred 

 to (p. 678). 



The localities at which the greatest development in the methods 

 of manufacture have occurred are E-osendale, Akrou and Buffalo, 



Bosendale region 



The cement quarries are located at Rosendale, Lawrenceville, 

 Binnewater, Rondout and East Kingston. Owing to the great 

 amount of rock overlying the cement bed, and its variable dips 

 (seldom less than 25° and sometimes as much as 75° or 80°), the 



l Hall, James. Yates county, (see Geol. 4th dist. N. Y. p. 458) 

 Wright, B. H. Notes on geology of Yates county, N. Y. {see 35th an. rep't 

 N. Y. state mus. p. 195) 



