This folder contains correspondence and other documents relating to the operations of the West Orange laboratory. Included are letters concerning the testing of coal tar and oil for use in Edison's ore milling process, the return of patent materials to his library, and the search for a picture of the original phonograph for exhibit at the World's Columbian Exposition in Chicago. There is also a list of dynamo motors at the laboratory and the Edison Phonograph Works, compiled by Arthur E. Kennelly.
All of the documents have been selected. Courtesy of Thomas Edison National Historical Park.