Edison Portland Cement Company
This company was incorporated on June 7, 1899, in New Jersey, to acquire Edison's process and patents for manufacturing cement in the United States and Canada. The company had a mill at Stewartsville, New Jersey, and sales offices in New York City, Boston and Philadelphia, as well as several southern states. During 1908 its patents were combined in a manufacturers' pool headed by the North American Portland Cement Company. The company was dissolved in December 1931. It was succeeded by the Edison Cement Corporation, which continued to manufacture cement until June 1942.