This folder contains correspondence and other documents relating primarily to the Stewartsville works, legal matters, and market conditions. Most of the letters are addressed to Edison. Among the other correspondents are Walter S. Mallory, Herman E. Kiefer, William H. Mason, and Harry F. Miller. There are numerous letters pertaining to product quality and testing. Included are references to tests on cement briquettes, experiments with mixtures of sugar and cement, and work with an experimental humidor. Some of the letters contain evaluations of materials for packaging cement, including waterproof and paper-lined bags. Others discuss the burning of buckwheat and gas coal in the kilns. There are also letters regarding limestone, cement sales, and the operations of other cement companies, including the federal antitrust suit involving the North American Portland Cement Co. Additional documents relate to an abandoned patent for waterproofed belting; agreements governing the use of Edison's long-kiln patent and his crushing technologies; and the receivership of the New Jersey and Pennsylvania Concentrating Works. A few letters concern Edison's schedule and visitors to the laboratory.

Approximately 50 percent of the documents have been selected. The unselected material includes monthly statements of cement sales and items concerning crushing roll contracts, royalties, and expenses.