This letterbook covers the period March 1881-January 1882. Most of the correspondence is by Edison. There is also correspondence by Samuel Insull. Most of Edison's letters are in the hand of Insull, acting as Edison's secretary. The correspondence relates primarily to electric lighting. Included are letters concerning the construction of the Holborn Viaduct central station in London, the use of batteries for electric lighting, and the development of dynamos and lamps. There are also letters pertaining to electric railway patent interferences, the periodical Science, and the Paris Electrical Exhibition of 1881. Among the recipients are Joshua F. Bailey, Charles Batchelor, the Edison Electric Lamp Co., George E. Gouraud, Edward H. Johnson, and Theodore Puskas. The front cover is marked "1881." The spine is stamped "Letters." The book contains 497 numbered pages and an index. Approximately 30 percent of the book has been selected. Courtesy of Thomas Edison National Historical Park.