Includes letters and memoirs relating to the telegraph: 1) letter in English, dated 1846, Samuel F. B. Morse to Alexander Humbolt concerning the telegraph invented by Morse (Morse 1); 2)letters, written by Wilhelm Eduard Weber (1804-1891), inventor of the first electromagnetic telegraph, as follows: an open letter, dated 1833, printed as a poster, to the Municipal Council (or local authority) about the electrotelegraph and the reply (Weber 1); copies of letters, dated 1833, concerning experiments of the electrical telegraph (Weber 2); personally written letter, dated 1833, to H. Von Stephan thanking him for his letter, in which he honors [Dr. Weber] for his 50 years work in the field of telegraphy and sends him a world map of telegraph transmission (Weber 3); 3) letter from Max Wein (1866-1938) to his cousin Wilhelm Wien about the wireless telegraphy at the front (Wien 1); 4) autograph letter in French dated 1868 by David Edward Hughes (1831-1890), English technician and inventor of the typeprint-telegraph and carbon microphone, to manufacturer Scheffler or Schaeffler) concerning the production of single parts of the Hughes-telegraph apparatus and introduction of it in Austria, Hungary, Bavaria, and Wurttemburg. Sketches included. (Hughes 1); 5) letters written by Franz August (Etzel) O'Etzel (1785-1850), dated 1846, with other materials; envelope contains letters with construction details of the electromagnetic telegraph of Steinhill and Wheatstone, as well as a print model of the Faraday-telegraph, and Morse tapes from the earliest time (E 51) as well as a bound handwritten memoir of telegraphy in France with diagrams and sketches.