Telegraphy

Telegraphy is a way to send messages over long distances using special codes that both the sender and receiver understand. Instead of sending a letter or package, people used symbols or signals to share information quickly. One early example is the flag semaphore, where people used flags to send messages from far away. But older systems, like sending messages with pigeon post, didn’t use codes and so aren’t considered true telegraphy.

The first widely used telegraph was the Chappe telegraph, created by Claude Chappe in the late 1700s. It used a series of moving arms that could be seen from a distance. This system helped France and other countries communicate during a busy time in history. Later, the electric telegraph became more popular in the 1800s. In Britain, Cooke and Wheatstone made a version that helped with railway signalling. In the United States, Samuel Morse created another system that became very common around the world.

Even after electric wires were used, some places kept using other ways to send messages. The heliograph used bright sunlight to send signals, especially in places without wires. Later, wireless telegraphy let people send messages without wires, which was very useful for ships at sea. As time went on, sending messages by telegraph became less common because new technologies like the telephone and the Internet offered faster and cheaper ways to talk to each other.

Terminology

The word telegraph comes from Ancient Greek, meaning "to write at a distance." It was first used by a French inventor who created a special signaling system.

A telegraph is a tool for sending and getting messages far away. Usually, this means using electricity. Sending messages without wires, using radio, is called wireless telegraphy. Telegraphy is the way of sending messages or symbols over long distances, often using electrical systems.

Some people think the true telegraph started in 1832 when an early electrical telegraph was invented. Messages sent this way were called telegrams. There were also special messages sent through underwater wires, called cablegrams. Later, messages could be sent through networks similar to phones, called Telex. Pictures could also be sent this way from far places.

History

Early signalling

Passing messages by signalling over distance is an ancient practice. One of the oldest examples is the signal towers of the Great Wall of China. By 400 BC, signals could be sent by beacon fires or drum beats, and by 200 BC complex flag signalling had developed. During the Han dynasty (202 BC – 220 AD), signallers mainly used flags and wood fires to send signals. By the Tang dynasty (618–907) a message could be sent 1,100 kilometres (700 mi) in 24 hours. The Ming dynasty (1368–1644) used artillery as another possible signalling method. While the signalling was complex, only predetermined messages could be sent. The Chinese signalling system extended well beyond the Great Wall.

Signal fires were widely used in Europe and elsewhere for military purposes. The Roman army made frequent use of them. Few details have been recorded of European/Mediterranean signalling systems. One system known is a system invented by Aeneas Tacticus (4th century BC). Signals sent by means of torches indicated when to start and stop draining.

None of the signalling systems discussed above are true telegraphs in the sense of a system that can transmit arbitrary messages over arbitrary distances. Lines of signalling relay stations can send messages to any required distance, but all these systems are limited in the range of messages that they can send. A system like flag semaphore, with an alphabetic code, can send any given message, but the system is designed for short-range communication between two persons. An engine order telegraph, used to send instructions from the bridge of a ship to the engine room, fails to meet both criteria; it has a limited distance and very simple message set. There was only one ancient signalling system described that does meet these criteria. That was a system using the Polybius square to encode an alphabet. Polybius (2nd century BC) suggested using two successive groups of torches to identify the coordinates of the letter of the alphabet being transmitted.

Optical telegraph

An optical telegraph is a telegraph consisting of a line of stations in towers or natural high points which signal to each other by means of shutters or paddles. Signalling by means of indicator pointers was called semaphore. Early proposals for an optical telegraph system were made to the Royal Society by Robert Hooke in 1684 and were first implemented on an experimental level by Sir Richard Lovell Edgeworth in 1767. The first successful optical telegraph network was invented by Claude Chappe and operated in France from 1793. The two most extensive systems were Chappe's in France, with branches into neighbouring countries, and the system of Abraham Niclas Edelcrantz in Sweden.

During 1790–1795, at the height of the French Revolution, France needed a swift and reliable communication system. In 1790, the Chappe brothers set about devising a system of communication. On 2 March 1791, at 11 am, they sent the message between Brulon and Parce, a distance of 16 kilometres (10 mi).

In 1792, Claude was appointed and charged with establishing a line of stations between Paris and Lille, a distance of 230 kilometres (140 mi). It was used to carry dispatches for the war between France and Austria. In 1794, it brought news of a French capture from the Austrians less than an hour after it occurred. A decision to replace the system with an electric telegraph was made in 1846, but it took a decade before it was fully taken out of service.

The Prussian system was put into effect in the 1830s. However, they were highly dependent on good weather and daylight to work and even then could accommodate only about two words per minute. The last commercial semaphore link ceased operation in Sweden in 1880. As of 1895, France still operated coastal commercial semaphore telegraph stations, for ship-to-shore communication.

Electrical telegraph

The early ideas for an electric telegraph included in 1753 using electrostatic deflections of pith balls, proposals for electrochemical bubbles in acid by Campillo in 1804 and von Sömmering in 1809. The first experimental system over a substantial distance was by Ronalds in 1816 using an electrostatic generator. Ronalds offered his invention to the British Admiralty, but it was rejected as unnecessary.

Eventually, electrostatic telegraphs were abandoned in favour of electromagnetic systems. An early experimental system (Schilling, 1832) led to a proposal to establish a telegraph between St Petersburg and Kronstadt, but it was never completed. The first operative electric telegraph (Gauss and Weber, 1833) connected Göttingen Observatory to the Institute of Physics about 1 km away during experimental investigations.

The first commercial telegraph was by Cooke and Wheatstone following their English patent of 10 June 1837. It was demonstrated on the London and Birmingham Railway in July of the same year. In July 1839, a five-needle, five-wire system was installed to provide signalling over a record distance of 21 km on a section of the Great Western Railway between London Paddington station and West Drayton. However, in trying to get railway companies to take up his telegraph more widely, Cooke was rejected several times.

Most of the early electrical systems required multiple wires, but the system developed in the United States by Morse and Vail was a single-wire system. This was the system that first used the soon-to-become-ubiquitous Morse code. By 1844, the Morse system connected Baltimore to Washington, and by 1861 the west coast of the continent was connected to the east coast.

The electric telegraph quickly became a means of more general communication. The Morse system was officially adopted as the standard for continental European telegraphy in 1851 with a revised code, which later became the basis of International Morse Code. However, Great Britain and the British Empire continued to use the Cooke and Wheatstone system, in some places as late as the 1930s.

Railway telegraphy

Railway signal telegraphy was developed in Britain from the 1840s onward. It was used to manage railway traffic and to prevent accidents as part of the railway signalling system. On 12 June 1837 Cooke and Wheatstone were awarded a patent for an electric telegraph. This was demonstrated between Euston railway station—where Wheatstone was located—and the engine house at Camden Town—where Cooke was stationed, together with Robert Stephenson, the London and Birmingham Railway line's chief engineer.

The concept of a signalling "block" system was proposed by Cooke in 1842. Railway signal telegraphy did not change in essence from Cooke's initial concept for more than a century. In this system each line of railway was divided into sections or blocks of varying length. Entry to and exit from the block was to be authorised by electric telegraph and signalled by the line-side semaphore signals, so that only a single train could occupy the rails.

Wigwag

Wigwag is a form of flag signalling using a single flag. Unlike most forms of flag signalling, which are used over relatively short distances, wigwag is designed to maximise the distance covered—up to 32 km (20 mi) in some cases. Wigwag achieved this by using a large flag and using motions rather than positions as its symbols since motions are more easily seen. It was invented by US Army surgeon Albert J. Myer in the 1850s who later became the first head of the Signal Corps. Wigwag was used extensively during the American Civil War where it filled a gap left by the electrical telegraph.

Heliograph

A heliograph is a telegraph that transmits messages by flashing sunlight with a mirror, usually using Morse code. The idea for a telegraph of this type was first proposed as a modification of surveying equipment (Gauss, 1821). Various uses of mirrors were made for communication in the following years, mostly for military purposes, but the first device to become widely used was a heliograph with a moveable mirror (Mance, 1869). The system was used by the French during the 1870–71 siege of Paris, with night-time signalling using kerosene lamps as the source of light.

Another type of heliograph was the heliostat or heliotrope fitted with a Colomb shutter. The heliostat was essentially a surveying instrument with a fixed mirror and so could not transmit a code by itself.

The heliograph was heavily used by Nelson A. Miles in Arizona and New Mexico after he took over command (1886) of the fight against Geronimo and other Apache bands in the Apache Wars. Miles had previously set up the first heliograph line in the US between Fort Keogh and Fort Custer in Montana. He used the heliograph to fill in vast, thinly populated areas that were not covered by the electric telegraph.

Use of the heliograph declined from 1915 onwards, but remained in service in Britain and British Commonwealth countries for some time. Australian forces used the heliograph as late as 1942 in the Western Desert Campaign of World War II.

Teleprinter

A teleprinter is a telegraph machine that can send messages from a typewriter-like keyboard and print incoming messages in readable text with no need for the operators to be trained in the telegraph code used on the line. It developed from various earlier printing telegraphs and resulted in improved transmission speeds.

Automated punched-tape transmission

In a punched-tape system, the message is first typed onto punched tape using the code of the telegraph system—Morse code for instance. It is then, either immediately or at some later time, run through a transmission machine which sends the message to the telegraph network. Multiple messages can be sequentially recorded on the same run of tape. The advantage of doing this is that messages can be sent at a steady, fast rate making maximum use of the available telegraph lines.

Oceanic telegraph cables

A worldwide communication network meant that telegraph cables would have to be laid across oceans. On land, cables could be run uninsulated suspended from poles. Underwater, a good insulator that was both flexible and capable of resisting the ingress of seawater was required. A solution presented itself with gutta-percha, a natural rubber from the Palaquium gutta tree, after William Montgomerie sent samples to London from Singapore in 1843.

Getting a cable across the Atlantic Ocean proved much more difficult. The Atlantic Telegraph Company, formed in London in 1856, had several failed attempts. A cable laid in 1858 worked poorly for a few days before being destroyed by applying too high a voltage. Its failure and slow speed of transmission prompted Thomson and Oliver Heaviside to find better mathematical descriptions of long transmission lines. The company finally succeeded in 1866 with an improved cable laid by SS Great Eastern, the largest ship of its day, designed by Isambard Kingdom Brunel.

An overland telegraph from Britain to India was first connected in 1866 but was unreliable, prompting a submarine telegraph cable to be connected in 1870. Several telegraph companies were combined to form the Eastern Telegraph Company in 1872. Australia was first linked to the rest of the world in October 1872 by a submarine telegraph cable at Darwin.

From the 1850s until well into the 20th century, British submarine cable systems dominated the world system. This was set out as a formal strategic goal, which became known as the All Red Line. In 1896, there were thirty cable-laying ships in the world and twenty-four of them were owned by British companies. In 1892, British companies owned and operated two-thirds of the world's cables and by 1923, their share was still 42.7 percent.

Facsimile

In 1843, Scottish inventor Alexander Bain invented a device that could be considered the first facsimile machine. Bain's telegraph was able to transmit images by electrical wires. Frederick Bakewell made several improvements on Bain's design and demonstrated a telefax machine. In 1855, an Italian priest, Giovanni Caselli, also created an electric telegraph that could transmit images. Caselli called his invention "Pantelegraph".

In 1881, English inventor Shelford Bidwell constructed the scanning phototelegraph that was the first telefax machine to scan any two-dimensional original, not requiring manual plotting or drawing.

Wireless telegraphy

The late 1880s through to the 1890s saw the discovery and then development of a newly understood phenomenon into a form of wireless telegraphy, called Hertzian wave wireless telegraphy, radiotelegraphy, or (later) simply "radio".

At the end of 1894, the young Italian inventor Guglielmo Marconi began working on the idea of building a commercial wireless telegraphy system based on the use of Hertzian waves (radio waves). Building on the ideas of previous scientists and inventors Marconi re-engineered their apparatus by trial and error attempting to build a radio-based wireless telegraphic system that would function the same as wired telegraphy. He would work on the system through 1895 in his lab and then in field tests making improvements to extend its range. After many breakthroughs, including applying the wired telegraphy concept of grounding the transmitter and receiver, Marconi was able, by early 1896, to transmit radio far beyond the short ranges that had been predicted. Having failed to interest the Italian government, the 22-year-old inventor brought his telegraphy system to Britain in 1896 and met William Preece, a Welshman, who was a major figure in the field and Chief Engineer of the General Post Office.

On 13 May 1897, Marconi, assisted by George Kemp, a Cardiff Post Office engineer, transmitted the first wireless signals over water to Lavernock (near Penarth in Wales) from Flat Holm. His star rising, he was soon sending signals across the English Channel (1899), from shore to ship (1899) and finally across the Atlantic (1901).

Telegram services

After electric telegraphy became available, companies or public entities offered telegram services - delivering telegraphed messages directly to the recipient. Earlier optical systems were largely limited to official government and military purposes.

Historically, telegrams were sent between a network of interconnected telegraph offices. A person visiting a local telegraph office paid by the word to have a message telegraphed to another office and delivered to the addressee on a paper form. Messages (i.e. telegrams) sent by telegraph could be delivered by telegraph messenger faster than mail, and even in the telephone age, the telegram remained popular for social and business correspondence.

Telegram services still operate in much of the world, but e-mail and text messaging have rendered telegrams obsolete in many countries, and the number of telegrams sent annually has been declining rapidly since the 1980s.

Telex

Telex (telegraph exchange) was a public switched network of teleprinters. It used rotary-telephone-style pulse dialling for automatic routing through the network. It initially used the Baudot code for messages. Telex development began in Germany in 1926, becoming an operational service in 1933 run by the Reichspost (the German imperial postal service). It had a speed of 50 baud—approximately 66 words per minute.

Decline

Telegraph use began to permanently decline around 1920. The decline began with the growth of the use of the telephone. The decline was briefly postponed by the rise of special occasion congratulatory telegrams. Traffic continued to grow between 1867 and 1893 despite the introduction of the telephone in this period, but by 1900 the telegraph was definitely in decline.

There was a brief resurgence in telegraphy during World War I but the decline continued as the world entered the Great Depression years of the 1930s. After the Second World War new technology improved communication in the telegraph industry. Telegraph lines continued to be an important means of distributing news feeds from news agencies by teleprinter machine until the rise of the internet in the 1990s. For Western Union, one service remained highly profitable—the wire transfer of money. This service kept Western Union in business long after the telegraph had ceased to be important. In the modern era, the telegraph that began in 1837 has been gradually replaced by digital data transmission based on computer information systems.

Social implications

Governments often set up optical telegraph lines for military use, keeping them for official purposes only. Later, railway companies in Germany and the UK installed electric telegraph lines, which soon led to private companies in the UK and the US offering telegraph services to the public. This new way of communicating brought big changes to society and the global economy.

The electric telegraph changed how people shared information, making it faster than traditional mail. By the end of the 19th century, it became a common way for everyday people to send messages. Some people were worried about the telegraph, fearing it might change the quality of public discussions. The telegraph was very important for industries like finance, newspapers, and railways, helping businesses grow and making transactions easier over long distances. It also changed how news was reported, with journalists using it to send stories from far away. The need for accurate time to go with the railways led to the creation of standard time, which brought further changes to society.

In popular culture

The optical telegraph was quickly forgotten after it stopped being used, but while it was in use, many people in Europe knew about it. It appeared in many paintings from that time. Famous writers like Victor Hugo wrote poems about it, and it played important roles in novels such as Lucien Leuwen by Stendhal and The Count of Monte Cristo by Alexandre Dumas.

Rudyard Kipling wrote a poem celebrating submarine telegraph cables, expressing a common belief in the late 1800s that such technology could help bring peace and understanding between countries. When the first submarine cable connected America and Britain, the New York Post wrote that it marked the start of a time when wars would become impossible.

Newspaper names

Many newspapers around the world, like The Daily Telegraph in Britain, The Telegraph in India, De Telegraaf in the Netherlands, and the Jewish Telegraphic Agency in the US, were named after the telegraph because they used it to get their news. Some still use these names today, even though they now get news in different ways.