Indicates land telegraph cables, submarine cables, ship routes of steam and proposed lines, depths shown by soundings and the prime meridian: Greenwich. Includes: • Two double-column text articles: – Account of the invention and operation of the magnetic telegraph. – Description of the laying of submarine telegraph cables. • Tables of land and submarine telegraphs of the world • Morse telegraphic alphabet. • Portraits of Cyrus W. Field and Samuel FB Morse. • Cross section of the Niagara ship, laying the cable. • lustrations of cables, telegraphs. • Signal key and batteries. • A profile of the Atlantic Ocean on the telegraph plates.