This folder contains correspondence relating to ore mining and milling operations at Bechtelsville, Pennsylvania, and Ogden, New Jersey. Most of the letters are to and from Edison and Harry M. Livor, general manager. The letters deal mainly with equipment, mill capacity, and mining properties. Some items concern the steam plant, dust separator, belt machines with automatic feed, and ore drying. Approximately 50 percent of the documents have been selected. Courtesy of Thomas Edison National Historical Park.