Open main menu

Telegraphy

  (Redirected from Telegraph)
Replica of Claude Chappe's optical telegraph on the Litermont near Nalbach, Germany

Telegraphy (from Ancient Greek: τῆλε, têle, "at a distance" and γράφειν, gráphein, "to write") is the long-distance transmission of textual or symbolic (as opposed to verbal or audio) messages without the physical exchange of an object bearing the message. Thus semaphore is a method of telegraphy, whereas pigeon post is not.

Telegraphy requires that the method used for encoding the message be known to both sender and receiver. Many methods are designed according to the limits of the signalling medium used. The use of smoke signals, beacons, reflected light signals, and flag semaphore signals are early examples.

In the 19th century, the harnessing of electricity led to the invention of electrical telegraphy. The advent of radio in the early 20th century brought about radiotelegraphy and other forms of wireless telegraphy. In the Internet age, telegraphic means developed greatly in sophistication and ease of use, with natural language interfaces that hide the underlying code, allowing such technologies as electronic mail and instant messaging.

Contents

TerminologyEdit

The word "telegraph" was first coined by the French inventor of the Semaphore telegraph, Claude Chappe, who also coined the word "semaphore".[1]

A "telegraph" is a device for transmitting and receiving messages over long distances, i.e., for telegraphy. The word "telegraph" alone now generally refers to an electrical telegraph.

Wireless telegraphy, transmission of messages over radio with telegraphic codes.

Contrary to the extensive definition used by Chappe, Morse argued that the term telegraph can strictly be applied only to systems that transmit and record messages at a distance. This is to be distinguished from semaphore, which merely transmits messages. Smoke signals, for instance, are to be considered semaphore, not telegraph. According to Morse, telegraph dates only from 1832 when Pavel Schilling invented one of the earliest electrical telegraphs.[2]

A telegraph message sent by an electrical telegraph operator or telegrapher using Morse code (or a printing telegraph operator using plain text) was known as a telegram. A cablegram was a message sent by a submarine telegraph cable,[3] often shortened to a cable or a wire. Later, a Telex was a message sent by a Telex network, a switched network of teleprinters similar to a telephone network.

A wire picture or wire photo was a newspaper picture that was sent from a remote location by a facsimile telegraph. A diplomatic telegram, also known as a diplomatic cable, is the term given to a confidential communication between a diplomatic mission and the foreign ministry of its parent country.[4][5] These continue to be called telegrams or cables regardless of the method used for transmission.

Early signallingEdit

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. In 400 BC, signals could be sent by beacon fires or drum beats. By 200 BC complex flag signalling had developed, and by the Han dynasty (200 BC–220 AD) signallers had a choice of lights, flags, or gunshots to send signals. By the Tang dynasty (618–907) a message could be sent 700 miles in 24 hours. The Ming dynasty (1368–1644) added artillery to the possible signals. While the signalling was complex, for instance, different coloured flags could be used to indicate enemy strength, only predetermined messages could be sent.[6] The Chinese signalling system extended well beyond the Great Wall. Signal towers away from the wall were used to give early warning of an attack. Others were built even further out as part of the protection of trade routes, especially the Silk Road.[7]

Signal fires were widely used in Europe and elsewhere for military purposes. The Roman army made frequent use of them, as did their enemies, and the remains of some of the stations still exist. Few details have been recorded of the signalling systems and the possible messages. One of the few for which details are known is a system invented by Aeneas Tacticus (4th century BC). Tacitus's system had water filled pots at the two signal stations which were drained in synchronisation. Annotation on a floating scale indicated which message was being sent or received. Signals sent by means of torches indicated when to start and stop draining to keep the synchronisation.[8]

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 to one extent or another in the range of messages that they can send. A system like flag semaphore, with an alphabetic code, can certainly 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. The number of said torches held up signalled the grid square that contained the letter. The system would have been very slow for military purposes and there is no record of it ever being used.[8]

Optical telegraphEdit

 
Construction schematic of a Prussian optical telegraph (or semaphore) tower, C. 1835

An optical telegraph, or semaphore 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. Early proposals for an optical telegraph system were made to the Royal Society by Robert Hooke in 1684[9] and were first implemented on an experimental level by Sir Richard Lovell Edgeworth in 1767.[10]

The first successful optical telegraph network was invented by Claude Chappe and operated in France from 1793 to 1846.[11]

 
Demonstration of the semaphore

During 1790–1795, at the height of the French Revolution, France needed a swift and reliable communication system to thwart the war efforts of its enemies. In 1790, the Chappe brothers set about devising a system of communication that would allow the central government to receive intelligence and to transmit orders in the shortest possible time. On 2 March 1791, at 11 am, they sent the message "si vous réussissez, vous serez bientôt couverts de gloire" (If you succeed, you will soon bask in glory) between Brulon and Parce, a distance of 16 kilometres (9.9 mi). The first means used a combination of black and white panels, clocks, telescopes, and codebooks to send their message.

In 1792, Claude was appointed Ingénieur-Télégraphiste and charged with establishing a line of stations between Paris and Lille, a distance of 230 kilometres (about 143 miles). It was used to carry dispatches for the war between France and Austria. In 1794, it brought news of a French capture of Condé-sur-l'Escaut from the Austrians less than an hour after it occurred.[12]

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.[13]

Electrical telegraphEdit

 
Cooke and Wheatstone's five-needle, six-wire telegraph (1837)
 
A Morse key (c. 1900)

The early ideas for an electric telegraph included using electrostatic deflections of pith balls (1753),[14] and electrochemical bubbles in acid (Campillo (1804); von Sömmering, 1809).[15] The first experimental system over a substantial distance was electrostatic (Ronalds, 1816).[16] Ronalds offered his invention to the British Admiralty, but it was rejected as unnecessary.[17] In the end, electrostatic telegraphs were abandoned in favour of electromechanical designs using electromagnets (electromagnetic systems). An early experimental electromagnetic system (Schilling, 1832) led to a proposal to establish a telegraph between St Petersburg and Kronstadt, but it was never completed.[18]

The first electric telegraph in regular use (Gauss and Weber, 1833) connected Göttingen Observatory to the Institute of Physics about 1 km away.[19] The first commercial telegraph (Cooke and Wheatstone, 1837) was initially provided for signalling on a section of the Great Western Railway in 1838.[20]

Most of these early systems required multiple wires (Ronalds' system was an exception), but the system developed in the United States (Morse and Vail, 1837) 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.[citation needed] The Cooke and Wheatstone telegraph, in a series of improvements, also ended up with a one-wire system, but still using their own code and needle displays.[20]

At first associated with the railways, the electric telegraph quickly became a means of more general communication. The Morse telegraph 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.[21] However, Great Britain and the British Empire continued to use the Cooke and Wheatstone system, in some places as late as the 1930s.[20] Likewise, the United States continued to use American Morse code internally, requiring translation operators skilled in both codes for international messages.[21]

Telegraphic improvementsEdit

Telegraphy was driven by the need to reduce sending costs, either in hand-work per message or by increasing the sending rate.[citation needed] While many experimental systems employing moving pointers and various electrical encodings proved too complicated and unreliable, a successful advance in the sending rate was achieved through the development of telegraphese.

 
The first message is received by the Submarine Telegraph Company in London from Paris on the Foy-Breguet instrument in 1851

The first system that didn't require skilled technicians to operate was Sir Charles Wheatstone's ABC system in 1840 where the letters of the alphabet were arranged around a clock-face, and the signal caused a needle to indicate the letter. This early system required the receiver to be present in real time to record the message and it reached speeds of up to 15 words a minute.

In 1846, Alexander Bain patented a chemical telegraph in Edinburgh. The signal current made a readable mark on a moving paper tape soaked in a mixture of ammonium nitrate and potassium ferrocyanide, which gave a blue mark when a current was passed through it.

 
A Baudot keyboard, 1884

David Edward Hughes invented the printing telegraph in 1855; it used a keyboard of 26 keys for the alphabet and a spinning type wheel that determined the letter being transmitted by the length of time that had elapsed since the previous transmission. The system allowed for automatic recording on the receiving end. The system was very stable and accurate and became the accepted around the world.[22]

The next improvement was the Baudot code of 1874. French engineer Émile Baudot patented a printing telegraph in which the signals were translated automatically into typographic characters. Each character was assigned a unique code based on the sequence of just five contacts. Operators had to maintain a steady rhythm, and the usual speed of operation was 30 words per minute.[23]

By this point, reception had been automated, but the speed and accuracy of the transmission were still limited to the skill of the human operator. The first practical automated system was patented by Charles Wheatstone, the original inventor of the telegraph. The message (in Morse code) was typed onto a piece of perforated tape using a keyboard-like device called the 'Stick Punch'. The transmitter automatically ran the tape through and transmitted the message at the then exceptionally high speed of 70 words per minute.

TeleprintersEdit

 
Phelps' Electro-motor Printing Telegraph from circa 1880, the last and most advanced telegraphy mechanism designed by George May Phelps

Teleprinters were invented in order to send and receive messages without the need for operators trained in the use of Morse code. A system of two teleprinters, with one operator trained to use a typewriter, replaced two trained Morse code operators. The teleprinter system improved message speed and delivery time, making it possible for messages to be flashed across a country with little manual intervention.[24]

Early teleprinters used the ITA-1 Baudot code, a five-bit code. This yielded only thirty-two codes, so it was over-defined into two "shifts", "letters", and "figures". An explicit, unshared shift code prefaced each set of letters and figures. In 1901, Baudot's code was modified by Donald Murray and around 1930, the CCITT introduced the International Telegraph Alphabet No. 2 (ITA2) code as an international standard.

 
A Siemens T100 Telex machine

By 1935, message routing was the last great barrier to full automation. Large telegraphy providers began to develop systems that used telephone-like rotary dialling to connect teletypewriters. These machines were called "Telex" (TELegraph EXchange). Telex machines first performed rotary-telephone-style pulse dialling for circuit switching and then sent data by Baudot code. This "type A" Telex routing functionally automated message routing.

Telex began in Germany as a research and development program in 1926 that became an operational teleprinter service in 1933. The service was operated by the Reichspost (Reich postal service) and had a speed of 50 baud – approximately 66 words-per-minute.

At the rate of 45.45 (±0.5%) baud—considered speedy at the time—up to 25 telex channels could share a single long-distance telephone channel by using voice frequency telegraphy multiplexing, making telex the least expensive method of reliable long-distance communication.

 
Western Union telegram circa 1930

Automatic teleprinter exchange service was introduced into Canada by CPR Telegraphs and CN Telegraph in July 1957, and in 1958, Western Union started to build a Telex network in the United States.[25]

Beginning in 1956,[26] telegrams begun to be transmitted over the Telex network using the ITU F.20 standard named Gentex in order to lower the costs for some European[26] telecommunications companies by allowing the sending telegraph station to connect directly to the receiving station.[27]

Oceanic telegraph cablesEdit

Soon after the first successful telegraph systems were operational, the possibility of transmitting messages across the sea by way of submarine communications cables was first mooted. One of the primary technical challenges was to insulate the submarine cable sufficiently to prevent the current from leaking out into the water. In 1842, a Scottish surgeon William Montgomerie[28] introduced Gutta-percha, the adhesive juice of the Palaquium gutta tree, to Europe. Michael Faraday and Wheatstone soon discovered the merits of gutta-percha as an insulator, and in 1845, the latter suggested that it should be employed to cover the wire which was proposed to be laid from Dover to Calais. It was tried on a wire laid across the Rhine between Deutz and Cologne.[citation needed] In 1849, C.V. Walker, electrician to the South Eastern Railway, submerged a two-mile wire coated with gutta-percha off the coast from Folkestone, which was tested successfully.[28]

John Watkins Brett, an engineer from Bristol, sought and obtained permission from Louis-Philippe in 1847 to establish telegraphic communication between France and England. The first undersea cable was laid in 1850 and connected London with Paris. After an initial exchange of greetings between Queen Victoria and President Napoleon, it was almost immediately severed by a French fishing vessel.[29] The line was relaid the next year[29] and then followed by connections to Ireland and the Low Countries.

 
The Eastern Telegraph Company network in 1901

The Atlantic Telegraph Company was formed in London in 1856 to undertake to construct a commercial telegraph cable across the Atlantic Ocean. It was successfully completed on 27 July 1866, by the ship SS Great Eastern, captained by Sir James Anderson after many mishaps along the way.[30] Earlier transatlantic submarine cables installations were attempted in 1857, 1858, and 1865. The 1858 cable only operated intermittently for a few days or weeks before it failed. The study of underwater telegraph cables accelerated interest in mathematical analysis of very long transmission lines. An overland telegraph from Britain to India was first connected in 1866 but was unreliable so a submarine telegraph cable was connected in 1870.[31] 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.[32] This brought news reportage from the rest of the world.[33] The telegraph across the Pacific was completed in 1902, finally encircling the world.

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.[34] 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.[35] During World War I, Britain's telegraph communications were almost completely uninterrupted while it was able to quickly cut Germany's cables worldwide.[34]

Later technologyEdit

FacsimileEdit

In 1843, Scottish inventor Alexander Bain invented a device that could be considered the first facsimile machine. He called his invention a "recording telegraph". 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 abbot, Giovanni Caselli, also created an electric telegraph that could transmit images. Caselli called his invention "Pantelegraph". Pantelegraph was successfully tested and approved for a telegraph line between Paris and Lyon.[36][37]

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. Around 1900, German physicist Arthur Korn invented the Bildtelegraph widespread in continental Europe especially since a widely noticed transmission of a wanted-person photograph from Paris to London in 1908 used until the wider distribution of the radiofax. Its main competitors were the Bélinographe by Édouard Belin first, then since the 1930s, the Hellschreiber, invented in 1929 by German inventor Rudolf Hell, a pioneer in mechanical image scanning and transmission.

Wireless telegraphyEdit

 
Post Office Engineers inspect Marconi's equipment on Flat Holm, May 1897

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". Between 1886 and 1888, Heinrich Rudolf Hertz published the results of his experiments where he was able to transmit electromagnetic waves (radio waves) through the air, proving James Clerk Maxwell's 1873 theory of electromagnetic radiation. Many scientists and inventors experimented with this new phenomenon but the general consensus was that these new waves (similar to light) would be just as short range as light, and, therefore, useless for long range communication.[38]

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), a line of inquiry that he noted other inventors did not seem to be pursuing.[39] 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.[40] 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. A series of demonstrations for the British government followed—by March 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (3.7 mi) across Salisbury Plain.

 
Marconi watching associates raising the kite (a "Levitor" by B.F.S. Baden-Powell[41]) used to lift the antenna at St. John's, Newfoundland, December 1901

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.[42] The message sent was "ARE YOU READY". From his Fraserburgh base, he transmitted the first long-distance, cross-country wireless signal to Poldhu in Cornwall.[when?][citation needed] His star rising, he was soon sending signals across The English channel (1899), from shore to ship (1899) and finally across the Atlantic (1901).[43] A study of these demonstrations of radio, with scientists trying to work out how a phenomenon predicted to have a short range could transmit "over the horizon", led to the discovery of a radio reflecting layer in the Earth's atmosphere in 1902, later called the ionosphere.[44]

Radiotelegraphy proved effective for rescue work in sea disasters by enabling effective communication between ships and from ship to shore. In 1904, Marconi began the first commercial service to transmit nightly news summaries to subscribing ships, which could incorporate them into their on-board newspapers. A regular transatlantic radio-telegraph service was finally begun on 17 October 1907.[45][46] Notably, Marconi's apparatus was used to help rescue efforts after the sinking of Titanic. Britain's postmaster-general summed up, referring to the Titanic disaster, "Those who have been saved, have been saved through one man, Mr. Marconi...and his marvellous invention."

InternetEdit

Around 1965, DARPA commissioned a study of decentralised switching systems. Some of the ideas developed in this study provided inspiration for the development of the ARPANET packet switching research network, which later grew to become the public Internet.

As the PSTN became a digital network, T-carrier "synchronous" networks became commonplace in the U.S. A T1 line has a "frame" of 193 bits that repeats 8000 times per second. The first bit called the "sync" bit alternates between 1 and 0 to identify the start of the frames. The rest of the frame provides 8 bits for each of 24 separate voice or data channels. Customarily, a T-1 link is sent over a balanced twisted pair, isolated with transformers to prevent current flow. Europeans adopted a similar system (E-1) of 32 channels (with one channel for frame synchronisation).

Later, SONET and SDH were adapted to combine carrier channels into groups that could be sent over optic fiber. The capacity of an optic fibre is often extended with wavelength division multiplexing, rather than rerigging new fibre. Rigging several fibres in the same structures as the first fibre is usually easy and inexpensive, and many fibre installations include unused spare "dark fibre", "dark wavelengths", and unused parts of the SONET frame, so-called "virtual channels".

In 2002, the Internet was used by Kevin Warwick at the University of Reading to communicate neural signals, in purely electronic form, telegraphically between the nervous systems of two humans,[47] potentially opening up a new form of communication combining the Internet and telegraphy.

In 2006, a well-defined communication channel used for telegraphy was established by the SONET standard OC-768, which sent about 40 gigabits per second.

The theoretical maximum capacity of an optic fibre is more than 1015 bits (one petabit or one quadrillion bits) per second.[48]

Since the Internet operates over any digital transmission medium, further evolution of telegraphic technology will be effectively concealed from users.

E-mailEdit

E-mail was first invented for CTSS and similar time sharing systems of the era in the mid-1960s.[49] At first, e-mail was possible only between different accounts on the same computer (typically a mainframe). ARPANET allowed different computers to be connected to allow e-mails to be relayed from computer to computer, with the first ARPANET e-mail being sent in 1971.[50] Multics also pioneered instant messaging between computer users in the mid-1970s. With the growth of the Internet, e-mail began to be possible between any two computers with access to the Internet.

Various private networks like UUNET (founded 1987), the Well (1985), and GEnie (1985) had e-mail from the 1970s, but subscriptions were quite expensive for an individual, US$25 to US$50 per month, just for e-mail. Internet use was then largely limited to government, academia, and other government contractors until the net was opened to commercial use in the 1980s.

By the early 1990s, modems made e-mail a viable alternative to Telex systems in a business environment. But individual e-mail accounts were not widely available until local Internet service providers were in place, although demand grew rapidly, as e-mail was seen as the Internet's killer app. It allowed anyone to email anyone, whereas previously, different system had been walled off from each other, such that America Online subscribers could email only other America Online subscribers, Compuserve subscribers could email only other Compuserve subscribers, etc. The broad user base created by the demand for e-mail smoothed the way for the rapid acceptance of the World Wide Web in the mid-1990s.[citation needed] Fax machines were another technology that helped displace the telegram.

On Monday, 12 July 1999, a final telegram was sent from the National Liberty Ship Memorial, the SS Jeremiah O'Brien, in San Francisco Bay to President Bill Clinton in the White House. Officials of Globe Wireless reported that "The message was 95 words, and it took six or eight minutes to copy it." They then transmitted the message to the White House via e-mail. That event was also used to mark the final commercial U.S. ship-to-shore telegraph message transmitted from North America by Globe Wireless, a company founded in 1911. Sent from its wireless station at Half Moon Bay, California, the sign-off message was a repeat of Samuel F. B. Morse's message 155 years earlier, "What hath God wrought?"[51]

Telegram servicesEdit

A telegram service is the delivery of written messages that have been sent by telegraph to a local telegraph office. These messages are delivered by hand to the addressee.

Telegram lengthEdit

The average length of a telegram in the 1900s in the US was 11.93 words; more than half of the messages were 10 words or fewer.[52]

According to another study, the mean length of the telegrams sent in the UK before 1950 was 14.6 words or 78.8 characters.[53]

For German telegrams, the mean length is 11.5 words or 72.4 characters.[53] At the end of the 19th century, the average length of a German telegram was calculated as 14.2 words.[53]

Social implicationsEdit

Prior to the electrical telegraph, ancient civilizations, such as Greece, Egypt, and China, transmitted long-distance information using drumbeats, flame beacons, or light flashes with a heliograph.[54] Later, nearly all information was limited to traveling at the speed of a human or animal. The telegraph freed communication from the time constraints of postal mail and revolutionized the global economy and society.[55][56] By the end of the 19th century, the telegraph was becoming an increasingly common medium of communication for ordinary people. The telegraph isolated the message (information) from the physical movement of objects or the process.[57]

Telegraphy facilitated the growth of organizations "in the railroads, consolidated financial and commodity markets, and reduced information costs within and between firms".[56] This immense growth in the business sectors influenced society to embrace the use of telegrams.

Worldwide telegraphy changed the gathering of information for news reporting. Messages and information would now travel far and wide, and the telegraph demanded a language "stripped of the local, the regional; and colloquial", to better facilitate a worldwide media language.[57] Media language had to be standardized, which led to the gradual disappearance of different forms of speech and styles of journalism and storytelling.

Newspaper namesEdit

Numerous newspapers and news outlets in various countries, such as The Daily Telegraph in Britain, The Telegraph in India, De Telegraaf in the Netherlands, and the Jewish Telegraphic Agency in the US, were given names which include the word "telegraph" due to their having received news by means of electric telegraphy. Some of these names are retained even though more sophisticated means are now used. A newspaper in Indian state of Tamil Nadu is named as Dhina Thanthi which means daily telegraph.

See alsoEdit

ReferencesEdit

  1. ^ Groundbreaking Scientific Experiments, Inventions & Discoveries of the 18th Century, Jonathan Shectman, p172
  2. ^ Samuel F. B. Morse, Examination of the Telegraphic Apparatus and the Processes in Telegraphy, pages 7–8, Philp & Solomons 1869 OCLC 769828711.
  3. ^ "Cablegram - Definition of cablegram by Merriam-Webster". merriam-webster.com.
  4. ^ "1,796 memos from US embassy in Manila in WikiLeaks 'Cablegate'". ABS–CBN Corporation. 29 November 2010. Retrieved 29 November 2010.
  5. ^ Definition of "cable", The Macquarie Dictionary (3rd ed.). Australia: Macquarie Library. 1997. ISBN 0-949757-89-6. (n.) 4. a telegram sent abroad, especially by submarine cable. (v.) 9. to send a message by submarine cable.
  6. ^ Christopher H. Sterling, "Great Wall of China", pp. 197-198 in, Christopher H. Sterling (ed), Military Communications: From Ancient Times to the 21st Century, ABC-CLIO, 2008 ISBN 1851097325.
  7. ^ Morris Rossabi, From Yuan to Modern China and Mongolia, p. 203, Brill, 2014 ISBN 9004285296.
  8. ^ a b David L. Woods, "Ancient signals", pp. 24-25 in, Christopher H. Sterling (ed), Military Communications: From Ancient Times to the 21st Century, ABC-CLIO, 2008 ISBN 1851097325.
  9. ^ "The Origin of the Railway Semaphore". Mysite.du.edu. Retrieved 2013-06-17.
  10. ^ Burns, Francis W. (2004). Communications: An International Historyof the Formative Years. IET. ISBN 978-0-86341-330-8.
  11. ^ "Semaphore, Encyclopædia Britannica".
  12. ^ How Napoleon's semaphore telegraph changed the world, BBC News, Hugh Schofield, 16 June 2013
  13. ^ "A Semaphore Telegraph Station", Scientific American Supplement, 20 April 1895, page 16087.
  14. ^ E. A. Marland, Early Electrical Communication, Abelard-Schuman Ltd, London 1964, no ISBN, Library of Congress 64-20875, pages 17–19;
  15. ^ Jones, R. Victor Samuel Thomas von Sömmering's "Space Multiplexed" Electrochemical Telegraph (1808–10), Harvard University website. Attributed to "Semaphore to Satellite", International Telecommunication Union, Geneva 1965.
  16. ^ Norman, Jeremy. "Francis Ronalds Builds the First Working Electric Telegraph(1816)". HistoryofInformation.com. Retrieved 1 May 2016.
  17. ^ Ronalds, B.F. (2016). "Sir Francis Ronalds and the Electric Telegraph". Int. J. for the History of Engineering & Technology. 86: 42. doi:10.1080/17581206.2015.1119481.
  18. ^ "Milestones:Shilling's Pioneering Contribution to Practical Telegraphy, 1828–1837". IEEE Global History Network. IEEE. Retrieved 26 July 2011.
  19. ^ R. W. Pohl, Einführung in die Physik, Vol. 3, Göttingen (Springer) 1924
  20. ^ a b c Anton A. Huurdeman, The Worldwide History of Telecommunications (2003) p. 67-69
  21. ^ a b Lewis Coe, The Telegraph: A History of Morse's Invention and Its Predecessors in the United States, McFarland, p. 69, 2003 ISBN 0786418087.
  22. ^ "David Edward Hughes". Clarkson University. April 14, 2007. Archived from the original on 2008-04-22. Retrieved 2010-09-29.
  23. ^ Beauchamp, K.G. (2001). History of Telegraphy: Its Technology and Application. IET. pp. 394–395. ISBN 0-85296-792-6.
  24. ^ "Typewriter May Soon Be Transmitter of Telegrams" (PDF), The New York Times, January 25, 1914
  25. ^ Phillip R. Easterlin, "Telex in New York", Western Union Technical Review, April 1959: 45
  26. ^ a b Heimbürger, Hans (1989). Svenska telegrafverket. Bd 6. Telefon, telegraf och radio 1946–1965. Stockholm: Televerket. pp. 233–236. LIBRIS 81400.
  27. ^ The international gentex service. ITU -T Recommendation ; F.20. ITU. 1993. Retrieved 2014-07-25.
  28. ^ a b Haigh, K R (1968). Cable Ships and Submarine Cables. London: Adlard Coles Ltd. pp. 26–27.
  29. ^ a b Solymar, Laszlo. The Effect of the Telegraph on Law and Order, War, Diplomacy, and Power Politics" in Interdisciplinary Science Reviews, Vol. 25, No. 3, pp. 204 f. 2000. Accessed 1 Aug 2014.
  30. ^ Wilson, Arthur (1994). The Living Rock: The Story of Metals Since Earliest Times and Their Impact on Civilization. p. 203. Woodhead Publishing. ISBN 978-1-85573-301-5.
  31. ^ G.C. Mendis (1952). Ceylon Under the British. Asian Educational Services. p. 96. ISBN 978-81-206-1930-2.
  32. ^ Briggs, Asa and Burke, Peter: "A Social History of the Media: From Gutenberg to the Internet", p110. Polity, Cambridge, 2005.
  33. ^ Conley, David and Lamble, Stephen (2006) The Daily Miracle: An introduction to Journalism,(Third Edition) Oxford University Press, Australia pp. 305–307
  34. ^ a b Kennedy, P. M. (October 1971). "Imperial Cable Communications and Strategy, 1870–1914". The English Historical Review. 86 (341): 728–752. doi:10.1093/ehr/lxxxvi.cccxli.728. JSTOR 563928.
  35. ^ Headrick, D.R., & Griset, P. (2001). Submarine telegraph cables: business and politics, 1838–1939. The Business History Review, 75(3), 543–578.
  36. ^ Istituto Tecnico Industriale, Rome, Italy. Italian biography of Giovanni Caselli
  37. ^ "The Institute of Chemistry - The Hebrew University of Jerusalem". huji.ac.il. Archived from the original on May 6, 2008.
  38. ^ view was held by Nikola Tesla, Oliver Lodge, Alexander Stepanovich Popov, amongst others (also Brian Regal, Radio: The Life Story of a Technology, page 22)
  39. ^ John W. Klooster (2009). Icons of Invention: The Makers of the Modern World from Gutenberg to Gates. ABC-CLIO. p. 161. ISBN 978-0-313-34743-6.
  40. ^ Sungook Hong, Wireless: From Marconi's Black-box to the Audion, MIT Press - 2001, page 21
  41. ^ First Atlantic Ocean crossing by a wireless signal. aerohistory.org. Retrieved on 12 July 2012.
  42. ^ "Marconi: Radio Pioneer". BBC South East Wales. Retrieved 2008-04-12.
  43. ^ "Letters to the Editor: Marconi and the History of Radio". IEEE Antennas and Propagation Magazine. 46 (2): 130. 2004. doi:10.1109/MAP.2004.1305565.
  44. ^ Victor L. Granatstein (2012). Physical Principles of Wireless Communications, Second Edition. CRC Press. p. 8. ISBN 978-1-4398-7897-2.
  45. ^ "The Clifden Station of the Marconi Wireless Telegraph System". Scientific American. 23 November 1907.
  46. ^ Second Test of the Marconi Over-Ocean Wireless System Proved Entirely Successful. Sydney Daily Post. 24 October 1907.
  47. ^ Warwick, K, Gasson, M, Hutt, B, Goodhew, I, Kyberd, P, Schulzrinne, H and Wu, X: "Thought Communication and Control: A First Step using Radiotelegraphy", IEE Proceedings on Communications, 151(3), pp. 185–189, 2004
  48. ^ "Maximum theoretical bandwidth of fibre-optics".
  49. ^ Tom Van Vleck. "The History of Electronic Mail".
  50. ^ Ray Tomlinson. "The First Network Email".
  51. ^ Quinn, Andrew (July 13, 1999). "It's Taps For U.S. Telegraph—Last Dots Dashed Out". San Francisco Chronicle (Reuters). Archived from the original on January 4, 2009. Retrieved 2009-01-06.
  52. ^ Hochfelder, David (2012). The Telegraph in America, 1832–1920. The Johns Hopkins University Press. p. 79. ISBN 9781421407470.
  53. ^ a b c Frehner, Carmen (2008). Email, SMS, MMS: The Linguistic Creativity of Asynchronous Discourse in the New Media Age. Bern: Peter Lang AG. pp. 187, 191. ISBN 9783039114511.
  54. ^ "Morse Code & the Telegraph - Inventions - HISTORY.com". HISTORY.com. Retrieved 2017-09-25.
  55. ^ Downey, Gregory J. (2002) Telegraph Messenger Boys: Labor, Technology, and Geography, 1850–1950, Routledge, New York and London, p. 7
  56. ^ a b Economic History Encyclopedia (2010) "History of the U.S. Telegraph Industry", "Archived copy". Archived from the original on 2006-05-02. Retrieved 2005-12-14.
  57. ^ a b Carey, James (1989). Communication as Culture, Routledge, New York and London, p. 210

Further readingEdit

  • Britton, John A. Cables, Crises, and the Press: The Geopolitics of the New International Information System in the Americas, 1866–1903. (University of New Mexico Press, 2013).
  • Fari, Simone. Formative Years of the Telegraph Union (Cambridge Scholars Publishing, 2015).
  • Fari, Simone. Victorian Telegraphy Before Nationalization (2014).
  • Hochfelder, David, The Telegraph in America, 1832–1920 (Johns Hopkins University Press, 2012).
  • Huurdeman, Anton A. The Worldwide History of Telecommunications (John Wiley & Sons, 2003)
  • John, Richard R. Network Nation: Inventing American Telecommunications (Harvard University Press; 2010) 520 pages; the evolution of American telegraph and telephone networks.
  • Kieve, Jeffrey L. (1973). The Electric Telegraph: a Social and Economic History. David and Charles. ISBN 0-7153-5883-9.
  • Lew, B., and Cater, B. "The Telegraph, Co-ordination of Tramp Shipping, and Growth in World Trade, 1870–1910", European Review of Economic History 10 (2006): 147–73.
  • Müller, Simone M., and Heidi JS Tworek. "'The telegraph and the bank': on the interdependence of global communications and capitalism, 1866–1914." Journal of Global History 10#2 (2015): 259–283.
  • O'Hara, Glen. "New Histories of British Imperial Communication and the 'Networked World' of the 19th and Early 20th Centuries" History Compass (2010) 8#7pp 609–625, Historiography,
  • Richardson, Alan J. "The cost of a telegram: Accounting and the evolution of international regulation of the telegraph." Accounting History 20#4 (2015): 405–429.
  • Standage, Tom (1998). The Victorian Internet. Berkley Trade. ISBN 0-425-17169-8.
  • Thompson, Robert Luther. Wiring a continent: The history of the telegraph industry in the United States, 1832–1866 (Princeton UP, 1947).
  • Wenzlhuemer, Roland. "The Development of Telegraphy, 1870–1900: A European Perspective on a World History Challenge." History Compass 5#5 (2007): 1720–1742.
  • Wenzlhuemer, Roland. Connecting the nineteenth-century world: The telegraph and globalization (Cambridge UP, 2013). online review
  • Winseck, Dwayne R., and Robert M. Pike. Communication & Empire: Media, Markets & Globalization, 1860–1930 (2007), 429pp.

TechnologyEdit

  • Armagnay, Henri (1908). "Phototelegraphy". Annual Report of the Board of Regents of the Smithsonian Institution: 197–207. Retrieved 2009-08-07.
  • Dargan, J. "The Railway Telegraph", Australian Railway Historical Society Bulletin, March, 1985 pp. 49–71
  • Gray, Thomas (1892). "The Inventors Of The Telegraph And Telephone". Annual Report of the Board of Regents of the Smithsonian Institution: 639–659. Retrieved 2009-08-07.
  • Pichler, Franz, Magneto-Electric Dial Telegraphs: Contributions of Wheatstone, Stoehrer and Siemens, The AWA Review vol. 26, (2013).
  • Ross, Nelson E. HOW TO WRITE TELEGRAMS PROPERLY The Telegraph Office (1928)
  • Wheen, Andrew;— DOT-DASH TO DOT.COM: How Modern Telecommunications Evolved from the Telegraph to the Internet (Springer, 2011) ISBN 978-1-4419-6759-6
  • Wilson, Geoffrey, The Old Telegraphs, Phillimore & Co Ltd 1976 ISBN 0-900592-79-6; us a comprehensive history of the shutter, semaphore and other kinds of visual mechanical telegraphs.

External linksEdit