914 NEW YORK STATE MUSEUM 



gained wide prominence for the quality of its cement. By 1840 

 the production of Rosendale and vicinity amounted to 600,000 

 barrels annually, and for a long time the district has been the 

 largest center of natural cement manufacture in this country. 

 According to F. H. Lewis,' the output in 1897 was approximately 

 3,500,000 barrels or 42% of the total reported for the United 

 States in that year. The natural rock of Erie county was first 

 used in 1839 when a mill was built at Akron. In 1870 a plant 

 was erected at Howes Cave, and in 1874 at Buffalo. 



The manufacture^bf Portland cement has been a development 

 of the last 25 years. ^^Its"^ growth at first was retarded, no doubt, 

 by the natural 'cement industry which commanded an extensive 

 market, but recently it has made rapid progress. Portland cement 

 was manufactured in 1881 by the Wallkill Portland Cement Co. 

 near South Rondout, the first plant (other than experimental) to 

 be erected in the State. The Empire Portland Cement Co. began 

 operations at Warner in 1886 and has been active almost con- 

 tinuously since that time. Among other localities which were 

 early identified with^he industry are Wayland, Glens Falls and 

 Montezuma. 



Crude materials adapted for cement manufacture are quite widely 

 distributed in New York, and are found at various geologic hor- 

 izons. In the Rosendale district the natural cement rock occurs in 

 the Cayugan series. Its thickness at Rondout is over 30 feet. 

 The rock is an impure magnesian limestone, containing 20% 

 or more of silica and alumina and 15 to 25% of magnesia. In 

 the central and western parts of the State, the cement beds are 

 mostl}^ of Salina age. At Buffalo and Akron they measure seven 

 or eight feet thick. 



For Portland cement the materials used include limestones, 

 marls, clays and shale. At one or two localities, limestone has 

 been found that can be ground and burned directly, yielding 

 a "natural Portland" cement, but generally a mixture of two 

 materials is necessary to secure the proper chemical composition. 

 The greater number of plants in the State employ a mixture of 

 limestone and clay. The limestones are from the Trenton, Helder- 

 berg and Tully formations, while the clays belong to the Quaternary. 

 A single plant owned by the Cayuga Cement Co. of Ithaca, employs 

 shale from the Hamilton series in place of clay. A mixture of 

 Quaternary marls and clays is used by four companies. 



The production of cement is carried on at present in 10 coimties 

 of the State: Columbia, Erie, Greene, Livingston, Onondaga, 



, i The Mineral Industry. 1898. v. 6. 



