Product Number: 3546
Telephone History Paperback for Sale on Amazon
Telephone Design Amazon Paperback
The complete development of Early Experimental Ideas, Invention & Design from 1830-1930, starting with the old Military and Naval Signal Flags still in use today, each flag spells an alphabetic message, letter by letter.
The next stage was the electric telegraph, the switching of electric current and needles, spelling out a letter-coded message.
Finally, the speaking telephone, now the mini-computer: camera /smartphone we know today, with easy downloads.
1.21 Early Experimental Ideas, Invention & Design: 1830-1930 Harrison Gray Dyar,1829 Dyar erected the first telegraph
line and dispatched its first telegraph message ever sent in America as determined by Levi Woodbury of the
Supreme Court of the United States. Dyar had used over half a mile of bare electrical wire to transmit the message.(1806-1879) and Professor Charles Wheatstone (1802-1875) entered into a partnership, and on 10th June patented a five-needle telegraph for which five wires were necessary. The telegraph worked by deflecting any two of the needles at the same time, to point to any one of 20 letters on the grid behind the needle. Sending and receiving messages was a slow process, as each
word had to be spelt out. With only 20 letters on the grid, the spelling sometimes contained inaccuracies. On
25 July, Wheatstone’s and Cooke’s telegraph was demonstrated to the directors of the London and Birmingham Railway between Euston and Camden Town, a distance of just under a mile. He employed mechanical and electrical means used by Samuel Morse many years later for the telegraph system he patented in 1847. The author Munroe explains that Dyar made his telegraph line at least eighteen years before the actual materialisation of the first practical Morse telegraph line was made between Washington, D.C. and Baltimore, Maryland. William Fothergill Cooke, Charles Wheatstone. In later systems the letter board was dispensed with and the code was read directly from the movement of the needles. This came about because the number of needles was reduced leading to more complex codes. The driver for this was the economic need to
reduce the number of telegraph wires used, which was related to the number of needles. An urgent need arose to do this with some of the early installations, which had deteriorating insulation causing some of the original wires to be unusable.
Cooke and Wheatstone’s most successful system was eventually a one-needle system which continued in service into the 1930s. Cooke and Wheatstone’s two-needle telegraph as used on the Great Western Railway.and Samuel Morse, using diffent methods of experimental and practical switching.Samuel F. B. Morse, the American physicist Joseph Henry, and Alfred Vail developed an electrical telegraph system. This system sent pulses of elect to recording sound 1860 and the Reis Transmitter, (all developed before A.G. Bell invented his telephone).
2.16 Pioneer Amateur & Professional Scientists, Engineers: Alexander Graham Bell, Joseph Henry and Alfred Vail.
3. 5 Examples of Early Telegraph/Telephones, original & modern reproductions.
4.29 Many new Telephone Companies: The Bell Telephone Company 1877, The National & International 1879, The American
Telephone & Telegraph Co.1899 and General Post Office, UK 1878.
5.18 Examples of early Construction & Operation of manual exchanges, Aerial lines and underground, Public kiosks K1-8,
Police boxes, Automobile AA and RAC kiosks. Telephone engineers and transport 1860-1960.
6.18 Europe quickly followed: British L.M.Ericsson Manufacturer Co.1903, G. Maconi, The Wire
less Telegraph & Signal Co.1909, The Plessey Co. 1917. Each country had its own state run public Telephone Systems.
7.28 Telephone History Visual Index with 114 engravings, all originals,
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