This folder contains correspondence and other documents relating to quadruplex telegraphy. Much of this material deals with litigation involving Edison, Western Union, and the Atlantic & Pacific Telegraph Co. A few of the documents relate to acoustic telegraphy and some concern a law allowing railroad companies to own telegraph companies. Much of the correspondence is by Edison's associates, Josiah C. Reiff and George B. Prescott.

All the documents have been selected except for duplicate copies of correspondence.