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1836
Electrical Telegraph
John Frederic Daniell (1790–1845), Joseph Henry (1797–1878), Samuel Morse (1791–1872), William Fothergill Cooke (1806–1879), Charles Wheatstone (1802–1875)
“Using electricity to send messages through wires was the subject of much experimentation in Europe and the United States during the early 19th century. The key invention was John Daniell’s wet-cell battery (1836), a reliable source of electricity. Various forms of metal wire had existed since ancient times, and air was a reasonably good insulator, so sending electricity over distance required little more than stringing up a wire, modulating the signal with some kind of code, and having a device at the other end to turn the coded electrical pulses back into something a human could perceive.
American inventor Samuel Morse is credited with inventing, patenting, and promoting the first practical telegraph in 1836. The original Morse system started with a message that was encoded as a series of bumps on small, puzzle-like pieces that were placed into a tray. The operator turned a crank that moved the tray past a switch that completed and broke an electric circuit as it moved up and down. At the other end, an electromagnet moved a fountain pen or pencil up and down as a strip of paper moved underneath. To transmit text, each letter and number needed to be translated into a series of electrical pulses, which we now call dots and dashes, after how they were recorded on the paper strip. To operate over distances, the Morse system relied on Joseph Henry’s amplifying electromechanical relay, which allowed faint electrical signals sent over a long distance to trigger a second circuit.
In England, meanwhile, William Fothergill Cooke and Charles Wheatstone developed their own telegraph system based on the ability of electricity moving through wire to deflect a magnetic compass. The original Cooke–Wheatstone telegraph used five needles arranged in a line on a board, along with a pattern of 20 letters: by sending electricity down a pair of wires, two of the needles would deflect and point at one of the letters.
Cooke and Wheatstone’s system was the first to be commercialized. A few years later, with $30,000 in federal funding, Morse built an experimental telegraph line from Washington, DC, to Baltimore, Maryland. On May 24, 1844, Morse sent his famous message—“What hath God wrought?”—between the two cities.”
SEE ALSO First Electromagnetic Spam Message (1864)
Drawings from Samuel Morse’s sketchbook, illustrating his first conception of the telegraph.
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