PLUM, William R. The Military Telegraph during the Civil War in the United States, with an Exposition of Ancient and Modern Means of Communication, and of the Federal and Confederate Cipher Systems; also a Running Account of the War between the States. Chicago: Jansen, McClurg & Company, 1882. 1st ed. 2 Vols. xii,-377;390pp. Portrait frontises., illus., portraits, maps. A very good copy in later 3/4 leather and marbled boards. "Stresses the role of the telegraph in each campaign; includes much information on operators, plus a section on cryptography" Nevins I, p.13.