London, New York, Bombay, Calcutta, Madras: Longmans, Green & Co. 1915. , x, 558 pages. Green cloth. A well worn exlibrary copy, with blue/green taped spine and portions of original spine laid down. Hinges loosening. Title page with perforated institutional label; label and remnants of labels on endpapers. Otherwise generally clean internally. A good working copy of a scarce title. Many illustrations throughout. Good. Cloth. 
Sterling/Shiers gives this work three stars (especially important or useful), noting it as "An important and detailed technical history, with emphasis on British and European developments. Photos, diagrams, tables, references, appendices, index"
Origins of Cyberspace #170.; Sterling/Shiers (History of Telecommunications Technology, An Annotated Bibliography: Scarecrow Press, 2000) #7-053.