Baudot Code – 1874 A.D.

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Baudot Code

Jean-Maurice-Émile Baudot (1845–1903), Donald Murray (1865–1945)

“Early telegraph systems relied on human operators to encode and transmit the sender’s message, and then to perceive, decode, and transcribe the message on paper upon receipt. Relying on human operators limited the maximum speed at which a message could be sent and required operator skills that were not easily available.

Émile Baudot developed a better approach. A trained French telegraph operator, Baudot devised a system that used a special keyboard with five keys (two for the left hand and three for the right) to send each character. Thirty-one different combinations arise from pressing one or more of the five keys together; Baudot assigned each code to a different letter of the alphabet. To send a message, the operator would type the codes in sequence as the machine clicked, roughly four times a second. With each click, a rotating part that Baudot called the distributor would read the position of each key in order and, if the key was pressed, send a corresponding pulse down the telegraph wire. At the other end, a remote printer would translate the codes back into a printed character on a piece of paper tape.

Baudot was one of the first people to combine key inventions by others into one working system. He patented his invention in 1874, started selling devices to the French Telegraph Administration in 1875, and was awarded the gold medal at the Paris Exposition Universelle in 1878. Baudot’s code was adopted as the International Telegraph Alphabet No. 1 (ITA1), one of the original international telecommunications standards. In recognition of his contribution, the baud, a unit of data transmission speed equal to the number of signal changes per second, is named after him.

In 1897, the Baudot system expanded to incorporate punched paper tape. The keyboard was disconnected from the telegraph line and connected to a new device that could punch holes across a strip of paper tape, with one hole corresponding to each key. Once punched, the tape could be loaded into a reader and the message sent down the telegraph wire faster than a human could type. In 1901, the inventor Donald Murray developed an easier-to-use punch that was based on a typewriter keyboard. Murray also made changes to Baudot’s code; the resulting code was known as the Baudot-Murray code (ITA2) and remained in use for more than 50 years.”

SEE ALSO ASCII (1963), Unicode (1992)

“Paper tape punched with the five-level Baudot code. The large holes correspond to the 5 bits of the code, while a rotating toothed tractor wheel fit into the small holes and used them to pull the tape through the machine.”

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First Electromagnetic Spam Message – 1864 A.D.

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First Electromagnetic Spam Message

“William Fothergill Cooke and Charles Wheatstone’s electromagnetic telegraph took England by storm shortly after commercial service began in 1837. By 1868, there were more than 10,000 miles of telegraph wire in the United Kingdom supporting 1,300 telegraph stations; four years later, there were 5,179 stations, serviced by more than 87,000 miles of wire.

With a capability to reach large numbers of people quickly and easily, the world’s first unsolicited, electrically enabled advertisement was sent in London late in the evening of May 29, 1864, according to historian Matthew Sweet. The message was from Messrs. Gabriel, a group of unregistered dentists, who sold a variety of false teeth, gums, toothpaste, and tooth powder.

The message, sent to current and former members of Parliament, read as follows:

Messrs. Gabriel, dentists, Harley-street, Cavendish-square. Until October Messrs. Gabriel’s professional attendance at 27, Harley-street, will be 10 till 5.

In 1864 there were no telegraphs in private residences; the message appeared on the swinging needles of the Cooke-Wheatstone electromagnetic telegraph, where it was transcribed by operators, carried by a boy sent from the London District Telegraph Company, and placed into the hand of a member of Parliament.

That M.P. wrote about his annoyance in a letter to the editor of the local paper: “I have never had any dealings with Messrs. Gabriel, and beg to know by what right do they disrupt me by a telegram which is simply the medium of advertisement? A word from you would, I feel sure, put a stop to this intolerable nuisance.”

But it wasn’t shame that put a halt to spam sent by telegram: it was the cost. Advertising by telegraph just wasn’t cost effective, due to the high price of sending the messages. That price plummeted with the birth of email, which was used to send a bulk, unsolicited advertisement for the first time in 1978.

SEE ALSO First Internet Spam Message (1978)

On May 29, 1864, Messrs. Gabriel, a group of unregistered dentists, sent members of the British Parliament the earliest known unsolicited electronic message. One recipient complained to the newspaper.

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Electrical Telegraph – 1836 A.D.

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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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Optical Telegraph – 1792 A.D.

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Optical Telegraph

Claude Chappe (1763–1805)

“People had used signal fires, torches, and smoke signals since ancient times to send messages rapidly over long distances. The ancient Athenians used flashes of sunlight from their shields to send messages from ship to shore. The Romans coded flags to send messages over a distance—a practice that the British Navy also employed as early as the 14th century.

In 1790, an out-of-work French engineer named Claude Chappe started a project with his brothers to develop a practical system for sending messages quickly over the French countryside. The idea was to set up a series of towers constructed on hills, with each tower in view of the next. Each tower would be equipped with a device that had big, movable arms and a telescope, so that the position of the arms could be determined and then relayed to the next tower. An operator in the first tower would move the arms into different positions, each position signaling a letter, and the operator in the second tower would write it down—essentially sending letters over distance (tele-graph) with light. A second telescope would allow for messages to be conveyed in the opposite direction.

After successfully sending a message nearly 9 miles (14 kilometers) on March 2, 1791, Claude and his younger brothers, Pierre François (1765–1834), René (1769–1854), and Abraham (1773–1849), moved to Paris to continue the experiments and drum up support from the new government. Their older brother, Ignace Chappe (1760–1829), was a member of the revolutionary Legislative Assembly, which probably helped somewhat. Soon the brothers were authorized by the Assembly to construct three stations as a test. That test went well, and in 1793 the Assembly decided to replace its system of couriers with optical telegraph lines. Claude Chappe was appointed lieutenant of engineering for the construction of a telegraph line between Paris and Lille, under the control of the Ministry of War.

The first practical demonstration of the telegraph came on August 30, 1794, when the Assembly learned that its army in Condé-sur-l’Escaut had been victorious. That message was transmitted in about half an hour. In the following years, telegraph lines were built across France, connecting all of the major cities. At its height, the system had 534 stations covering more than 3,000 miles (5,000 kilometers). Not surprisingly, Napoléon Bonaparte made heavy use of the technology during his conquest of Europe.”

SEE ALSO Fax Machine Patented (1843)

An artist’s impression of Claude Chappe, demonstrating his aerial telegraph semaphore system, from the Paris newspaper Le Petit Journal, 1901.”

Fair Use Source: B07C2NQSPV