THE MINING AND QUARRY INDUSTRY 53 



limitation of natural resources. In these respects the Hudson river 

 region and the central and western counties along the main trunk 

 lines and the Erie canal possess the greatest advantages. The 

 Hudson river region comprises Ulster county, the largest center 

 of the natural cement industry, and Greene, Columbia, Schoharie 

 and Warren counties which manufacture Portland cement. Among 

 the other counties, Onondaga and Erie have the greater number of 

 plants and their products include both Portland and natural cements. 

 Livingston, Steuben and Tompkins counties, which make Portland 

 cement, complete the list. 



Natural cement. New York has long been the leading producer 

 of natural rock cement. The first manufacturing plants were estab- 

 lished in Ulster and Onondaga counties soon after 1820. The growth 

 of the industry from the beginning was rapid. By 1840 there were 

 16 plants in Ulster county in the vicinity of Kingston, Rosendale, 

 Lawrenceville and High Falls, with a total of 60 kilns. The annual 

 production at that time is stated by Mather to have been 600,000 

 barrels. Owing to its excellent quality, Rosendale cement (the 

 trade name for the product of Ulster county) has been accepted as 

 the standard in all parts of the country. The industry reached its 

 highest point in the period from 1890 to 1900 with an average 

 annual output of 4,000,000 barrels. During the past few years the 

 industry has declined in importance owing to competition with 

 Portland cement. 



The rock employed in making natural cement in this State is an 

 impure limestone occurring near the top of the Siluric. In the 

 Rosendale district the cement series includes the Salina, Cobleskill 

 and Rondout beds. At Rondout, according to Van Ingen, there are 

 nine distinct layers or strata aggregating a little more than 30 feet 

 in thickness. The strata have been sharply folded and the methods 

 adopted in their excavation resemble those used in coal mining. In 

 Onondaga county there are two beds of cement rock belonging to 

 the Upper Manlius. The upper layer attains a thickness of 4 feet 

 at the eastern border of the county and is separated from the lower 

 layer which is over 4 feet thick by about 3 feet of blue limestone. 

 The principal quarries are near Manlius, Fayetteville and James- 

 ville. The cement rock in Erie county is the Bertie waterlime, 

 occurring at the top of the Salina, and has a thickness of 5 to 8 

 feet. The quarries are located at Akron, Falkirk and Buffalo. 



The cement rock varies considerably in chemical composition, but 

 in general it may be described as an impure dolomite or magnesian 

 limestone. The Rosendale rock contains 20 per cent or more of 



