This folder contains correspondence and other documents relating to the business of the Edison Crushing Roll Co., which licensed and installed Edison's crushing rolls and collected royalties for their use. Included are reports pertaining to the operations and output of licensees, along with correspondence concerning the collection of royalties. Also included is a letter bearing marginalia by Edison, in which he declines an invitation to visit the Dunbar Stone Co. in River Rouge, Michigan. Courtesy of Thomas Edison National Historical Park.