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The electromagnetic telegraph is a device that can send coded text messages over wire. In 1831, an American scientist, Joseph Henry, made an important discovery in electric induction which became the established underlying principles of the electric telegraph. Joseph Henry strung a mile of fine wire, placed an “intensity” battery at one end, and made the armature strike a bell at the other. This was the first discovery of the fact that a galvanic current could be transmitted to a great distance with so little a diminution of force as to produce mechanical effects, and of the means by which the underlying principle of transmission could be accomplished. In 1836, Dr. David Alter invented the world’s first practical electric telegraph, in Elderton, Pennsylvania, one year before the more popular Wheatstone and Morse telegraphs were invented. Alter demonstrated it to witnesses. Samuel F. B. Morse independently conceived the idea of electrical telegraphy beginning in 1832 when in 1835, an experimental electrical telegraph would soon follow. By October 3, 1837, an alternative design by Morse that he later filed a patent caveat for, was fully capable of transmitting over long distances of wire. An electrical telegraph came to refer to a signaling telegram, where an operator makes and breaks an electrical contact with a telegraph key, resulting in an audible signal at the other end produced by a telegraph sounder which is interpreted and transcribed by an operator. Beginning in 1832, Alfred Vail in collaboration with Samuel Morse, began the process of developing the Morse code signalling alphabet. The short and long elements can be formed by sounds, marks, or pulses, in on off keying and are commonly known as “dots” and “dashes” or “dits” and “dahs”. After some minor changes and exactly 134 years of use, Morse Code was standardized in 1865 at the International Telegraphy congress in Paris and later made the norm by the International Telecommunication Union as International Morse code. On January 31, 1999, international regulations no longer required ships at sea to call for help in an emergency using Morse code and the well-known SOS signal.
