Inventions and Discovery-----------Telegraph

Telegraph

An electrical telegraph is a telegraph that uses electrical signals, usually conveyed via dedicated telecommunication lines or radio. The electromagnetic telegraph is a device for human-to-human transmission of coded text messages.

A printing electrical telegraph receiver, with transmitter key at bottom right

The electrical telegraph, or more commonly just telegraph, superseded optical semaphore telegraph systems, such as the Transatlantic telegraph cable constructed by the British empire to link Britain and North America, Claude Chappe's cables designed for communication among the French military, and Friedrich Clemens Gerke for the Prussian military, thus becoming the first form of electrical telecommunications. In a matter of decades after their creation, electrical telegraph networks permitted people and commerce to transmit messages across both continents and oceans almost instantly, with widespread social and economic impacts.


Early work

From early studies of electricity, electrical phenomena were known to travel with great speed, and many experimenters worked on the application of electricity to communications at a distance.

All the known effects of electricity - such as sparks, electrostatic attraction, chemical changes, electric shocks, and later electromagnetism - were applied to the problems of detecting controlled transmissions of electricity at various distances.

In 1753 an anonymous writer in the Scots Magazine suggested an electrostatic telegraph. Using one wire for each letter of the alphabet, a message could be transmitted by connecting the wire terminals in turn to an electrostatic machine, and observing the deflection of pith balls at the far end. Telegraphs employing electrostatic attraction were the basis of early experiments in electrical telegraphy in Europe, but were abandoned as being impractical and were never developed into a useful communication system.

In 1800 Alessandro Volta invented the Voltaic Pile, allowing for a continuous current of electricity for experimentation. This became a source of a low-voltage current that could be used to produce more distinct effects, and which was far less limited than the momentary discharge of an electrostatic machine, which with Leyden jars were the only previously known man-made sources of electricity.

Another very early experiment in electrical telegraphy was an 'electrochemical telegraph' created by the German physician, anatomist and inventor Samuel Thomas von Sömmering in 1809, based on an earlier, less robust design of 1804 by Catalan polymath and scientist Francisco Salva Campillo.Both their designs employed multiple wires (up to 35) to represent almost all Latin letters and numerals. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmering's design), with each of the telegraph receiver's wires immersed in a separate glass tube of acid. An electric current was sequentially applied by the sender through the various wires representing each digit of a message; at the recipient's end the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver's operator would watch the bubbles and could then record the transmitted message.This is in contrast to later telegraphs that used a single wire (with ground return).

Sömmering's electric telegraph in 1809

Hans Christian Ørsted discovered in 1820 that an electric current produces a magnetic field which will deflect a compass needle. In the same year Johann Schweigger invented the galvanometer, with a coil of wire around a compass, which could be used as a sensitive indicator for an electric current. In 1821, André-Marie Ampère suggested that telegraphy could be done by a system of galvanometers, with one wire per galvanometer to indicate each letter, and said he had experimented successfully with such a system. In 1824, Peter Barlow said that such a system only worked to a distance of about 200 feet (61 m), and so was impractical.

In 1825 William Sturgeon invented the electromagnet, with a single winding of uninsulated wire on a piece of varnished iron, which increased the magnetic force produced by electric current. Joseph Henry improved it in 1828 by placing several windings of insulated wire around the bar, creating a much more powerful electromagnet which could operate a telegraph through the high resistance of long telegraph wires.

In 1835 Joseph Henry and Edward Davy invented the critical electrical relay. Davy's relay used a magnetic needle which dipped into a mercury contact when an electric current passed through the surrounding coil. This allowed a weak current to operate a powerful local electromagnet over very long distances.


First working systems

The first working electrostatic telegraph was built by the English inventor Francis Ronalds. He laid down eight miles of wire in insulated glass tubing in his garden and connected both ends to two clocks marked with the letters of the alphabet. Electrical impulses sent along the wire were used to transmit messages. He offered his invention to the Admiralty, describing it as "a mode of conveying telegraphic intelligence with great rapidity, accuracy, and certainty, in all states of the atmosphere, either at night or in the day, and at small expense." However, there was little official enthusiasm for his device in the aftermath of the Napoleonic Wars. He published an account of his apparatus in the 1823 Descriptions of an Electrical Telegraph, and of some other Electrical Apparatus.

The telegraph invented by Baron Schilling von Canstatt in 1832 had a transmitting device which consisted of a keyboard with 16 black-and-white keys. These served for switching the electric current. The receiving instrument consisted of six galvanometers with magnetic needles, suspended from the silk threads. Both stations of Shilling's telegraph were connected by eight wires; six were connected with the galvanometers, one served for the return current and one - for a signal bell. When at the starting station the operator pressed a key, the corresponding pointer was deflected at the receiving station. Different positions of black and white flags on different disks gave combinations which corresponded to the letters or numbers. Pavel Shilling subsequently improved its apparatus. He reduced the number of connecting wires from eight to two.

On 21 October 1832, Schilling managed a short-distance transmission of signals between two telegraphs in different rooms of his apartment. In 1836 the British government attempted to buy the design but Schilling instead accepted overtures from Nicholas I of Russia. Schilling's telegraph was tested on a 5-kilometre-long (3.1 mi) experimental underground and underwater cable, laid around the building of the main Admiralty in Saint Petersburg and was approved for a telegraph between the imperial palace at Peterhof and the naval base at Kronstadt. However, the project was cancelled following Schilling's death in 1837.Schilling was also one of the first to put into practice the idea of the binary system of signal transmission.

In 1833, Carl Friedrich Gauss, together with the physics professor Wilhelm Weber in Göttingen installed a 1,200-metre-long (3,900 ft) wire above the town's roofs. Gauss combined the Poggendorff-Schweigger multiplicator with his magnetometer to build a more sensitive device, the galvanometer. To change the direction of the electric current, he constructed a commutator of his own. As a result, he was able to make the distant needle move in the direction set by the commutator on the other end of the line.

At first, they used the telegraph to coordinate time, but soon they developed other signals; finally, their own alphabet. The alphabet was encoded in a binary code which was transmitted by positive or negative voltage pulses which were generated by means of moving an induction coil up and down over a permanent magnet and connecting the coil with the transmission wires by means of the commutator. The page of Gauss' laboratory notebook containing both his code and the first message transmitted, as well as a replica of the telegraph made in the 1850s under the instructions of Weber are kept in the faculty of physics of Göttingen University.

Gauss was convinced that this communication would be a help to his kingdom's towns. Later in the same year, instead of a Voltaic pile, Gauss used an induction pulse, enabling him to transmit seven letters a minute instead of two. The inventors and university were too poor to develop the telegraph on their own, but they received funding from Alexander von Humboldt. Carl August Steinheil in Munich was able to build a telegraph network within the city in 1835-6. He installed a telegraph line along the first German railroad in 1835.

Across the Atlantic, in 1836 an American scientist, Dr. David Alter, invented the first known American electric telegraph, in Elderton, Pennsylvania, one year before the Morse telegraph. Alter demonstrated it to witnesses but never developed the idea into a practical system. He was interviewed later for the book Biographical and Historical Cyclopedia of Indiana and Armstrong Counties, in which he said: "I may say that there is no connection at all between the telegraph of Morse and others and that of myself.... Professor Morse most probably never heard of me or my Elderton telegraph." 


Commercial telegraphy

The first commercial electrical telegraph, the Cooke and Wheatstone telegraph, was co-developed by William Fothergill Cooke and Charles Wheatstone. In May 1837 they patented a telegraph system which used a number of needles on a board that could be moved to point to letters of the alphabet. The patent recommended a five-needle system, but any number of needles could be used depending on the number of characters it was required to code. A four-needle system was installed between Euston and Camden Town in London on a rail line being constructed by Robert Stephenson between London and Birmingham. It was successfully demonstrated on 25 July 1837. Euston needed to signal to an engine house at Camden Town to start hauling the locomotive up the incline. As at Liverpool, the electric telegraph was in the end rejected in favour of a pneumatic system with whistles.

Cooke and Wheatstone's five-needle, six-wire telegraph



Cooke and Wheatstone had their first commercial success with a system installed on the Great Western Railway over the 13 miles (21 km) from Paddington station to West Drayton in 1838, the first commercial telegraph in the world. This was a five-needle, six-wire system. The cables were originally installed underground in a steel conduit. However, the cables soon began to fail as a result of deteriorating insulation and were replaced with uninsulated wires on poles. As an interim measure, a two-needle system was used with three of the remaining working underground wires, which despite using only two needles had a greater number of codes. But when the line was extended to Slough in 1843, a one-needle, two-wire system was installed.

From this point the use of the electric telegraph started to grow on the new railways being built from London. The Blackwall Tunnel Railway (another rope-hauled application) was equipped with the Cooke and Wheatstone telegraph when it opened in 1840, and many others followed. The one-needle telegraph proved highly successful on British railways, and 15,000 sets were still in use at the end of the nineteenth century. Some remained in service in the 1930s. In September 1845 the financier John Lewis Ricardo and Cooke formed the Electric Telegraph Company, the first public telegraphy company in the world. This company bought out the Cooke and Wheatstone patents and solidly established the telegraph business.

As well as the rapid expansion of the use of the telegraphs along the railways, they soon spread into the field of mass communication with the instruments being installed in post offices across the country. The era of mass personal communication had begun.

Morse system

An electrical telegraph was independently developed and patented in the United States in 1837 by Samuel Morse. His assistant, Alfred Vail, developed the Morse code signalling alphabet with Morse. The first telegram in the United States was sent by Morse on 11 January 1838, across two miles (3 km) of wire at Speedwell Ironworks near Morristown, New Jersey, although it was only later, in 1844, that he sent the message "WHAT HATH GOD WROUGHT" from the Capitol in Washington to the old Mt. Clare Depot in Baltimore.

 A Morse key


The Morse/Vail telegraph was quickly deployed in the following two decades; the overland telegraph connected the west coast of the continent to the east coast by 24 October 1861, bringing an end to the Pony Express.



Edward Davy demonstrated his telegraph system in Regent's Park in 1837 and was granted a patent on 4 July 1838. He also developed an electric relay.



Oceanic telegraph cables


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 sufficiently insulated the submarine cable to prevent the current from leaking out into the water. In 1842, a Scottish surgeon William Montgomerie 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. 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.

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, connecting the two countries and was followed by connections to Ireland and the Low Countries.


 Major telegraph lines in 1891


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 18 July 1866 by the ship SS Great Eastern, captained by Sir James Anderson after many mishaps along the away.Earlier transatlantic submarine cables installations were attempted in 1857, 1858 and 1865. The 1857 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. The telegraph lines from Britain to India were connected in 1870 (those several companies 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.This brought news reportage from the rest of the world. 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.[29] 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. During World War I, Britain's telegraph communications were almost completely uninterrupted, while it was able to quickly cut Germany's cables worldwide.


A Timeline History of  Telegraph


Prior to 1300
FIRE, SMOKE, BELLS, TRUMPETS, DRUMS AND GUNS

1300 to today
FLAGS AND SEMAPHORE

1800
Telegraph defined from the Greek... TELE = Afar GRAPHOS = Write

1809
First telegraph in Bavaria. Samuel Soemmering. Used 35 wires with gold electrodes in water. Detection at distant end 2000 feet away was by the amount of gas caused by electrolysis.

1828
First telegraph in the USA. Harrison Dyar sent electrical sparks through chemically treated paper tape to burn dots and dashes.

1840
Samuel F.B. Morse and Alfred Vail were issued a patent for the first practical telegraph based on electromagnets. Relays were used every 10 miles to repeat the signals. In Morse coding there are 11 different characters between American and European codes.

1845
Samuel Morse and Alfred Vail introduce a Morse printer that uses ink and electromagnets to print dots and dashes on paper tape.







1846
Royal E. House of Vermont produces a printing telegraph that uses paper tape, a type-wheel and a piano style keyboard. One key for each character.

1856
David Hughes, a music professor in Kentucky uses a vibrating spring tuned to a specific pitch to synchronize the sending and receiving teleprinter with use a code invented by him.                                                                                                 



1865
Telegraph becomes the greatest means of communications ever. Over 83,000 miles of wire in the USA alone dedicated to telegraph. At the same time development of the telephone begins.

1874
J.M.E. Baudot in France invents the multiplex telegraph system where at least 4 stations can transmit simultaneously (actually serially) through the use of a distributor. The transmitters are like a miniature piano with five keys. Each combination of keys equals a character. Paper tape is used as the printed media.                        



                                              


1880
Baudot's 5 unit code forms the basis for the european standard CCITT International Telegraph Alphabet No. 1 (ITA-1)

1901
Donald Murray improves the 5 unit code with new character assignments and adds two shifts. This becomes the basis of CCITT Alphabet No. 2 (ITA-2) which is still in use one hundred years later.

1902-1907
Charles Krum perfects the 5 unit ITA-2 code with a start-stop sequence to allow teletypewriters to be used in commercial applications. One coded character is 7.42 unit intervals.

e.g. START, ONE, TWO, THREE, FOUR, FIVE, STOP= 1.42 unit intervals made possible the mass mechanization of telegraph.

Jay Morton of the Morton Salt dynasty funded Krum's experiments.

1906
The Morkrum Company was established with its ownership shared by Charles Krum and the Morton family.

1908
The Morkrum Company developed its first commercial printer. A field trial was conducted with the Alton Railroad. The trial was successful, but the Alton Railroad made no purchase.

1910
The Postal Telegraph purchased the first commercial Morkrum equipment. In 1912, Western Union (having split from Western Electric) purchased the same device. Although these M10 units were mechanically successful, none were commercially successful until 1925.

1915
The Associated Press adopted Morkrum M10 printing telegraph equipment to provide simultaneous service to competitive newspapers in New York City.  
                                                         



1918
Morkrum Company operation was expanded from its "garage" type facility. Employees numbered "over 200".

1921
The M11 type-wheel tape printer, went into production. It constituted the first commercially acceptable and successful unit, The M11 was manufactured through 1927 with 883 machines being produced.                           
                                                                      
     
                                                            

1922
The M12, a type-bar page printer with moving platen, was first marketed. Previous to 1922, printing telegraph was limited largely to commercial-telegraph and railroad uses. The M12 page printer opened the way to general business uses. Substantial numbers of this unit were sold through 1930, with quantity, too, being sold as late as 1943. A total of 11,899 M12 units were sold.

1925
The M14 type-bar tape printer was first marketed. The machine reached its highest production in 1929 and 1930. A total of 60,000 units had been sold when the device was manufacture discontinued in the late 1950s.

1925
The Morkrum & Kleinschmidt Companies merged to form the Morkrum-Kleinschmidt Company.

1929
The title Morkrum-Kleinschmidt was found to be too cumbersome and was dropped in favor of "Teletype."

1930
The M15 type-bar page printer with stationary platen was introduced. This machine soon became the "bread and butter" unit of Teletype, reaching its peak output during WWII. Through 1954, about 200,000 were sold. A large percentage of Bell System Teletypewriter Exchange (TWX) stations were of the M15 vintage.

1930
The Teletype Corporation was purchased by the Bell System and became a wholly owned subsidiary of the Western Electric Corporation. The Bell System at this time, was formulating plans for a new teletypewriter exchange service called TWX. The Teletype Corporation was selected and purchased to provide the necessary equipment for the proposed service.

1932
TWX (Teletypewriter Exchange Service) was inaugurated by the Bell System. Terminal equipment provided by the Teletype Corporation was of the M15 type.

1941
The M14 tape punch was first marketed. Approximately 50,000 units were sold through the late 1950s when the device was manufacture discontinued. About 90% of all effort at Teletype was devoted to the war.

1946-1950
Models 19 and 20 developed for auto-control of transmission - 19ASR and for 6 unit teletypesetting - the Model 20

1951
The first M28 page printer was delivered to the Navy. This represented approximately 12 years of research and development effort. The M28 line was accepted by the Bell System as a successor to the M14, 15 and 19 lines of equipment in 1956. The M28 design principle constituted the corporations basic approach to both message and data recording equipment until 1960.

1953
The first "DataPhone" is developed by Bell Laboratories. About the size of a small desk it operates totally analog circuitry at the speed of 50 bps. Model 29 was scheduled to replace the Model 20, but it never happened. Model 31RO and KSR Tape Printer is invented for the miliary.

1960
Teletype Corporation assembles for the first time under one roof in their new quarters in Skokie, Illinois. A multi-million dollar plant with a million and a half square feet of operating area and employing over 6,000 workers, it represented a milestone in the history of the Teletype Corporation. Manual TWX stations are all converted to dial.

1961
The Model TT-242 is rejected by the Navy in favor of the MITE compact teletypewriter. It becomes the basis for the model 32 and 33. The M35 and M33 lines of equipment. While the M35 is merely an 8 level version of the M28, the M33 represented the marriage of many proven designs into a totally new design, best described by the term "low cost concept." Approximately 6 years of research and development went into the Models 242, 32 and 33.

1962
First generation Bell System DataPhones (modems) are sold commercially. Speeds offered are from 45 to 2400 bits per second.

1962-1974
American Standard Code for Information Interchange (ASCII) as a standard code set is developed and standardized by Electronic Industry Association (EIA)

1966
Analog Wide-Band Data service is first offered using specially built facilities able to transmit and receive data at 50 kilobits per second. Don House starts with Illinois Bell Telephone Co., the highest revenue earner in the Bell System with over 44,000 employees.

1968
The first and longest strike against the Bell System by members of the Communications Workers of America and the International Brotherhood of Electrical Workers. The strike lasts almost 6 months.

1972
Digital Data Service (DDS) is started up by the Bell System offering synchronous digital data communications services from 2400 bits per second (bps) to 56000 (56K) bps. DDS is the single greatest advance in the history of data communications by pioneering the transmission of totally high speed digital signals.

1968-1978
Much development goes into new concepts and new forms of data station equipment. "Machines that make data move" becomes Teletypes trade slogan. Devices such as the Dataspeed paper tape senders and receivers operating at 750 - 2000 words per minute. The Inktronic printer that sprayed 80 characters at a time on a roll of paper at 2400 words a minute. R & D is working overtime on new projects for the Bell System and the government. TWX is sold to Western Union.

1978-1979
Second generation Dataphones now offered by the Bell System at speeds up to 19200 bps. Increased competition takes away sales.

1979-1984
The Teletype Corporation produced the newer "Black line" of Model 40, 4540 electronic display terminals and chain type based printers. The Models 42 and 43 dot matrix terminals are introduced. They also produced the Magnetic Tape Terminal as an adjunct for both the Models 43, and 40 lines of equipment.

1984-1989
Divestiture of the Bell System. Teletype name is dropped along with its logo to be replaced by AT&T and the "Death Star" logo. Operations in Skokie are discontinued and operations consolidate in Little Rock, Arkansas. Many employees are laid off. Then the operation in Little Rock manufacturing the 5310 terminals and printers is closed down and moved to Singapore, China.

1984-1996
It was during this period that Don House founded and began what is now incorporated as the North American Data Communications Museum (NADCOMM) a California Not-For-Profit, Public Benefit Corporation. The museum collective now has 5 locations across the country. The museum is operated and administered solely by volunteers, mostly veterans of the data communication revolution.

2001
All that is left of the Bell System and Teletype Corporation is what is in the history books and in our memories. Approximately 12,000 Teletype machines world wide still exist in the hands of third world countries, amateur radio operators and collectors.


End of the Telegraph Era

In the United States, Western Union discontinued all telegram and commercial messaging services on 27 January 2006,although it still offered its electronic money transfer services.
India's state-owned telecom company, BSNL, ended its telegraph service on 14 July 2013. It was reportedly the world's last existing true electric telegraph system.

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