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96-555: In 1931, ACA was founded as the American Radio Telegraphists Association (ARTA) by Mervyn Rathbone. The union represented telegraphists and radio operators (on land and at sea) in the United States. The union had previously been involved in a Supreme Court case regarding the use of strikebreakers in strikes ( NLRB v. Mackay Radio & Telegraph Co. , 304 U.S. 333 (1938)), which it had lost. In 1937,

192-497: A 175-yard (160 m) long trench as well as an eight-mile (13 km) long overhead telegraph. The lines were connected at both ends to revolving dials marked with the letters of the alphabet and electrical impulses sent along the wire were used to transmit messages. Offering his invention to the Admiralty in July 1816, it was rejected as "wholly unnecessary". His account of the scheme and

288-560: A bar magnet. This machine was made by Carl August von Steinheil . The Gauss and Weber telegraph remained in daily service until 1838. In 1836, the Leipzig–Dresden railway inquired whether the Gauss and Weber telegraph could be installed on their line. The laboratory instrument was much too cumbersome, and much too slow to be used in this way. Gauss asked Steinheil to develop something more practical for railway use. This he did, producing

384-475: 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 moved an iron pen across a moving paper tape soaked in a mixture of ammonium nitrate and potassium ferrocyanide, decomposing

480-442: A compact needle instrument which also emitted sounds while it was receiving messages. The needle struck one of two bells, on the right and left respectively, when it was deflected. The two bells had different tones so that the operator could tell which way the needle had been deflected without constantly watching it. Steinheil first installed his telegraph along five miles of track covering four stations around Munich. In 1838, he

576-464: A demonstration of principle. Meanwhile, Pavel Schilling in Russia constructed a series of telegraphs also using Schweigger multipliers. The exact date that Schilling switched from developing electrochemical telegraphs to needle telegraphs is not known, but Hamel says he showed one in early development to Tsar Alexander I who died in 1825. In 1832, Schilling developed the first needle telegraph (and

672-468: 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 letter 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

768-529: A mechanical telegraph based on a musical snuff box. In this device the detent of the clockwork mechanism was released by the armature of an electromagnet. Cooke carried out this work extremely quickly. The needle telegraph was completed within three weeks, and the mechanical telegraph within six weeks of seeing Muncke's demonstration. Cooke attempted to interest the Liverpool and Manchester Railway in his mechanical telegraph for use as railway signalling, but it

864-674: A moving paper tape by a stylus which was operated by an electromagnet. Morse and Vail developed the Morse code signalling alphabet . On May 24, 1844, Morse sent to Vail the historic first message “ WHAT HATH GOD WROUGHT " from the Capitol in Washington to the old Mt. Clare Depot in Baltimore . The first commercial electrical telegraph was the Cooke and Wheatstone system . A demonstration four-needle system

960-538: A much better match for ideal damping . The five-needle telegraph was first put into service with the Great Western Railway in 1838. However, it was soon dropped in favour of two-needle and single-needle systems. The cost of multiple wires proved to be a more important factor than the cost of training operators. In 1846, Cooke formed the Electric Telegraph Company with John Lewis Ricardo ,

1056-541: A much improved design. This was taken up by several railway companies. Cooke's Electric Telegraph Company , formed in 1846, provided the first public telegraph service. The needle telegraphs of the Electric Telegraph Company and their rivals were the standard form of telegraphy for the better part of the nineteenth century in the United Kingdom. They continued in use even after the Morse telegraph became

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1152-565: A permanent magnet and connecting the coil with the transmission wires by means of the commutator. The page of Gauss's 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 at the University of Göttingen , in Germany. Gauss was convinced that this communication would be of help to his kingdom's towns. Later in

1248-426: A practical alphabetical system in 1840 called the A.B.C. System, used mostly on private wires. This consisted of a "communicator" at the sending end and an "indicator" at the receiving end. The communicator consisted of a circular dial with a pointer and the 26 letters of the alphabet (and four punctuation marks) around its circumference. Against each letter was a key that could be pressed. A transmission would begin with

1344-490: A received telegraph pulse. According to Stuart M. Hallas, needle telegraphs were in use on the Great Northern Line as late as the 1970s. The telegraph code used on these instruments was the Morse code . Instead of the usual dots and dashes of different durations, but the same polarity, needle instruments used pulses of the same duration, but opposite polarities to represent the two code elements. This arrangement

1440-545: A sensitive indicator for an electric current. Also that year, André-Marie Ampère suggested that telegraphy could be achieved by placing small magnets under the ends of a set of wires, one pair of wires for each letter of the alphabet. He was apparently unaware of Schweigger's invention at the time, which would have made his system much more sensitive. In 1825, Peter Barlow tried Ampère's idea but only got it to work over 200 feet (61 m) and declared it impractical. In 1830 William Ritchie improved on Ampère's design by placing

1536-583: 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

1632-405: A steady rhythm, and the usual speed of operation was 30 words per minute. 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 message (in Morse code ) was typed onto a piece of perforated tape using a keyboard-like device called

1728-467: A telegraph along the Nuremberg–Fürth railway line , built in 1835 as the first German railroad, which was the first earth-return telegraph put into service. By 1837, William Fothergill Cooke and Charles Wheatstone had co-developed a telegraph system which used a number of needles on a board that could be moved to point to letters of the alphabet. Any number of needles could be used, depending on

1824-477: A useful communication system. In 1774, Georges-Louis Le Sage realised an early electric telegraph. The telegraph had a separate wire for each of the 26 letters of the alphabet and its range was only between two rooms of his home. In 1800, Alessandro Volta invented the voltaic pile , providing 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

1920-507: The Telegraph Industry ." Appearing under subpoena were the union's lawyer Victor Rabinowitz , ACA president Joseph Selly, ACA secretary-treasurer Joseph Kehoe, executive board member Louis Siebenberg, ACA vice president Dominick Rocco Panza, ACA recording secretary Mollie Townsend, ACA Local 40 chairman John Wieners, ACA Local 40 secretary-treasurer Alfred Doumar, and ACA publicity director Charles Silberman. Hostile witnesses against ACA

2016-451: The University of Göttingen and the university astronomical observatory about a mile and a half away where they were studying the Earth's magnetic field. The line consisted of a pair of copper wires on posts above rooftop height. The receiving instrument they used was a converted laboratory instrument, of which the so called needle was a large bar magnet weighing a pound. In 1834, they replaced

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2112-470: 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. An early successful teleprinter was invented by Frederick G. Creed . In Glasgow he created his first keyboard perforator, which used compressed air to punch the holes. He also created a reperforator (receiving perforator) and a printer. The reperforator punched incoming Morse signals onto paper tape and

2208-631: The 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs , that were devised to send text messages more quickly than physically carrying them. Electrical telegraphy can be considered the first example of electrical engineering . Text telegraphy consisted of two or more geographically separated stations, called telegraph offices . The offices were connected by wires, usually supported overhead on utility poles . Many electrical telegraph systems were invented that operated in different ways, but

2304-468: The Cooke and Wheatstone system did not require a common wire. Instead of Schilling's binary code, current was sent through one wire to one needle's coil and returned via the coil and wire of another. This scheme was similar to that employed by Samuel Thomas von Sömmerring on his chemical telegraph, but with a much more efficient coding scheme. Sömmerring's code required one wire per character . Even better,

2400-565: 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 . In the 1930s, teleprinters were produced by Teletype in the US, Creed in Britain and Siemens in Germany. By 1935, message routing

2496-571: The Imperial palace at Tsarskoye Selo and Kronstadt Naval Base . 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

2592-455: The Morse system became the standard for international communication, using a modified form of Morse's code that had been developed for German railways. Electrical telegraphs were used by the emerging railway companies to provide signals for train control systems, minimizing the chances of trains colliding with each other. This was built around the signalling block system in which signal boxes along

2688-519: The Morse system. 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 . The era of mass personal communication had begun. Telegraph networks were expensive to build, but financing was readily available, especially from London bankers. By 1852, National systems were in operation in major countries: The New York and Mississippi Valley Printing Telegraph Company, for example,

2784-578: 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. The writer has never been positively identified, but the letter was signed C.M. and posted from Renfrew leading to a Charles Marshall of Renfrew being suggested. 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

2880-539: 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

2976-536: The armature was intended to make marks on paper tape, but operators learned to interpret the clicks and it was more efficient to write down the message directly. In 1851, a conference in Vienna of countries in the German-Austrian Telegraph Union (which included many central European countries) adopted the Morse telegraph as the system for international communications. The international Morse code adopted

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3072-420: The bar, creating a much more powerful electromagnet which could operate a telegraph through the high resistance of long telegraph wires. During his tenure at The Albany Academy from 1826 to 1832, Henry first demonstrated the theory of the 'magnetic telegraph' by ringing a bell through one-mile (1.6 km) of wire strung around the room in 1831. In 1835, Joseph Henry and Edward Davy independently invented

3168-403: The bubbles and could then record the transmitted message. This is in contrast to later telegraphs that used a single wire (with ground return). Hans Christian Ørsted discovered in 1820 that an electric current produces a magnetic field that will deflect a compass needle. In the same year Johann Schweigger invented the galvanometer , with a coil of wire around a compass, that could be used as

3264-685: The chemical and producing readable blue marks in Morse code. The speed of the printing telegraph was 16 and a half words per minute, but messages still required translation into English by live copyists. Chemical telegraphy came to an end in the US in 1851, when the Morse group defeated the Bain patent in the US District Court. For a brief period, starting with the New York–Boston line in 1848, some telegraph networks began to employ sound operators, who were trained to understand Morse code aurally. Gradually,

3360-447: The communicator. Pressing another key would then release the pointer and the previous key, and re-connect the magneto to the line. These machines were very robust and simple to operate, and they stayed in use in Britain until well into the 20th century. The Morse system uses a single wire between offices. At the sending station, an operator taps on a switch called a telegraph key , spelling out text messages in Morse code . Originally,

3456-579: The east coast by 24 October 1861, bringing an end to the Pony Express . France was slow to adopt the electrical telegraph, because of the extensive optical telegraph system built during the Napoleonic era . There was also serious concern that an electrical telegraph could be quickly put out of action by enemy saboteurs, something that was much more difficult to do with optical telegraphs which had no exposed hardware between stations. The Foy-Breguet telegraph

3552-436: The effect on the compass was seriously diminished "with only 200 feet of wire". Barlow, and other eminent academics of the time who agreed with him, were criticised by some writers for retarding the development of the telegraph. A decade passed between Ampère's paper being read and the first electromagnetic telegraphs being built. It was not until 1829 that the idea of applying Schweigger style multipliers to telegraph needles

3648-504: 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, Gauss and Weber used the telegraph to coordinate time, but soon they developed other signals and finally, their own alphabet. The alphabet was encoded in a binary code that was transmitted by positive or negative voltage pulses which were generated by means of moving an induction coil up and down over

3744-605: The electric telegraph, visual systems were used, including beacons , smoke signals , flag semaphore , and optical telegraphs for visual signals to communicate over distances of land. An auditory predecessor was West African talking drums . In the 19th century, Yoruba drummers used talking drums to mimic human tonal language to communicate complex messages – usually regarding news of birth, ceremonies, and military conflict – over 4–5 mile distances. From early studies of electricity , electrical phenomena were known to travel with great speed, and many experimenters worked on

3840-407: The electrical telegraph. The Foy-Breguet telegraph is usually described as a needle telegraph, but electrically it is actually a type of armature telegraph. The needles are not moved by a galvanometer arrangement. They are instead moved by a clockwork mechanism that the operator must keep wound up. The detent of the clockwork is released by an electromagnetic armature which operates on the edges of

3936-464: The first company to offer a telegraph service to the public. They continued to sell needle telegraph systems to railway companies for signalling, but they also slowly built a national network for general use by businesses, the press, and the public. Needle telegraphs were officially superseded by the Morse telegraph when the UK telegraph industry was nationalised in 1870, but some continued in use well in to

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4032-419: The first electromagnetic telegraph of any kind) intended for practical use. Tsar Nicholas I initiated a project to connect St. Petersburg with Kronstadt using Schilling's telegraph, but it was cancelled on Schilling's death in 1837. Schilling's scheme had some drawbacks. Although it used far fewer wires than proposed by Ampère or used by Ritchie, his 1832 demonstration still used eight wires, which made

4128-516: The first means of radiowave telecommunication, which he began in 1894. In the early 20th century, manual operation of telegraph machines was slowly replaced by teleprinter networks. Increasing use of the telephone pushed telegraphy into only a few specialist uses; its use by the general public dwindled to greetings for special occasions. The rise of the Internet and email in the 1990s largely made dedicated telegraphy networks obsolete. Prior to

4224-408: The first of which was the synchronisation of clocks in the two buildings. Within a few months, they developed a telegraph code that allowed them to send arbitrary messages. Signalling speeds were around seven characters per minute. In 1835, they replaced the batteries of their telegraph with a large magneto-electric apparatus which generated telegraph pulses as the operator moved a coil relative to

4320-601: The first telegraph of any kind used commercially, was the Cooke and Wheatstone telegraph , employed in Britain and the British Empire in the 19th and early-20th centuries, due to Charles Wheatstone and William Fothergill Cooke . The inspiration to build a telegraph came in March 1836 when Cooke saw one of Schilling's needle instruments demonstrated by Georg Wilhelm Muncke in a lecture in Heidelberg (although he did not realise that

4416-440: The instrument was due to Schilling). Cooke was supposed to be studying anatomy, but immediately abandoned this and returned to England to develop telegraphy. He initially built a three-needle telegraph, but believing that needle telegraphs would always require multiple wires, he moved to mechanical designs. His first effort was a clockwork telegraph alarm, which later went into service with telegraph companies. He then invented

4512-453: The line communicate with neighbouring boxes by telegraphic sounding of single-stroke bells and three-position needle telegraph instruments. In the 1840s, the electrical telegraph superseded optical telegraph systems such as semaphores, becoming the standard way to send urgent messages. By the latter half of the century, most developed nations had commercial telegraph networks with local telegraph offices in most cities and towns, allowing

4608-592: The magnet in Ampère's scheme would have been very weak because he did not form the wire into a coil around the needle to multiply the magnetic effect of the current. Johann Schweigger had already invented the galvanometer (in September) using such a multiplier, but Ampère either had not yet got the news, or failed to realise its significance for a telegraph. Peter Barlow investigated Ampère's idea, but thought it would not work. In 1824 he published his results, saying that

4704-420: The magnet with an even heavier one, variously reported as 25, 30, and 100 pounds. The magnet moved so minutely a telescope was required to observe a scale reflected from it by a mirror. The initial purpose of this line was not telegraphic at all. It was used to confirm the correctness or otherwise of the then recent work of Georg Ohm , that is, they were verifying Ohm's law . They quickly found other uses,

4800-491: The magnetic needles inside a coil of wire connected to each pair of conductors. He successfully demonstrated it, showing the feasibility of the electromagnetic telegraph, but only within a lecture hall. 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

4896-473: The mercury dipping electrical relay , in which a magnetic needle is dipped into a pot of mercury when an electric current passes through the surrounding coil. In 1837, Davy invented the much more practical metallic make-and-break relay which became the relay of choice in telegraph systems and a key component for periodically renewing weak signals. Davy demonstrated his telegraph system in Regent's Park in 1837 and

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4992-432: The most widely used of its type was the Cooke and Wheatstone telegraph , invented in 1837. The second category are armature systems, in which the current activates a telegraph sounder that makes a click; communication on this type of system relies on sending clicks in coded rhythmic patterns. The archetype of this category was the Morse system and the code associated with it, both invented by Samuel Morse in 1838. In 1865,

5088-422: The number of characters it was required to code. In May 1837 they patented their system. The patent recommended five needles, which coded twenty of the alphabet's 26 letters. Samuel Morse independently developed and patented a recording electric telegraph in 1837. Morse's assistant Alfred Vail developed an instrument that was called the register for recording the received messages. It embossed dots and dashes on

5184-436: The official standard in the UK in 1870. Some were still in use well in to the twentieth century. The history of the needle telegraph began with the landmark discovery, published by Hans Christian Ørsted on 21 April 1820, that an electric current deflected the needle of a nearby compass. Almost immediately, other scholars realised the potential this phenomenon had for building an electric telegraph. The first to suggest this

5280-414: The ones that became widespread fit into two broad categories. First are the needle telegraphs, in which electric current sent down the telegraph line produces electromagnetic force to move a needle-shaped pointer into position over a printed list. Early needle telegraph models used multiple needles, thus requiring multiple wires to be installed between stations. The first commercial needle telegraph system and

5376-440: The other being the armature system, as exemplified by the telegraph of Samuel Morse in the United States. Needle telegraphs were widely used in Europe and the British Empire during the nineteenth century. Needle telegraphs were suggested shortly after Hans Christian Ørsted discovered that electric currents could deflect compass needles in 1820. Pavel Schilling developed a telegraph using needles suspended by threads. This

5472-415: The pointer reached the position of the depressed key, it would stop and the magneto would be disconnected from the line. The communicator's pointer was geared to the magneto mechanism. The indicator's pointer was moved by a polarised electromagnet whose armature was coupled to it through an escapement . Thus the alternating line voltage moved the indicator's pointer on to the position of the depressed key on

5568-410: The pointers on the dials at both ends set to the start position. The transmitting operator would then press down the key corresponding to the letter to be transmitted. In the base of the communicator was a magneto actuated by a handle on the front. This would be turned to apply an alternating voltage to the line. Each half cycle of the current would advance the pointers at both ends by one position. When

5664-507: The possibilities of rapid global communication in Descriptions of an Electrical Telegraph and of some other Electrical Apparatus was the first published work on electric telegraphy and even described the risk of signal retardation due to induction. Elements of Ronalds' design were utilised in the subsequent commercialisation of the telegraph over 20 years later. The Schilling telegraph , invented by Baron Schilling von Canstatt in 1832,

5760-558: The printer decoded this tape to produce alphanumeric characters on plain paper. This was the origin of the Creed High Speed Automatic Printing System, which could run at an unprecedented 200 words per minute. His system was adopted by the Daily Mail for daily transmission of the newspaper contents. With the invention of the teletypewriter , telegraphic encoding became fully automated. Early teletypewriters used

5856-497: The public to send messages (called telegrams ) addressed to any person in the country, for a fee. Beginning in 1850, submarine telegraph cables allowed for the first rapid communication between people on different continents. The telegraph's nearly-instant transmission of messages across continents – and between continents – had widespread social and economic impacts. The electric telegraph led to Guglielmo Marconi 's invention of wireless telegraphy ,

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5952-476: The receiving end. The system was very stable and accurate and became accepted around the world. 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 five-bit code, mechanically interpreted from the state of five on/off switches. Operators had to maintain

6048-450: 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 Schilling subsequently improved its apparatus by reducing the number of connecting wires from eight to two. On 21 October 1832, Schilling managed

6144-469: 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 did not have the funds 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 1835–1836. In 1838, Steinheil installed

6240-426: The sending rate. There were many experiments with moving pointers, and various electrical encodings. However, most systems were too complicated and unreliable. A successful expedient to reduce the cost per message was the development of telegraphese . The first system that did not require skilled technicians to operate was Charles Wheatstone's ABC system in 1840 in which the letters of the alphabet were arranged around

6336-452: The system expensive to install over very long distances. Schilling's scheme used a bank of six needle instruments which between them displayed a binary code representing a letter of the alphabet. Schilling did devise a code that allowed the letter code to be sent serially to a single needle instrument, but he found that the dignitaries he demonstrated the telegraph to could understand the six-needle version more readily. Transmission speed

6432-487: The twentieth century. The Henley-Foster telegraph was a needle telegraph used by the British and Irish Magnetic Telegraph Company , the main rival to the Electric Telegraph Company. It was invented in 1848 by William Thomas Henley and George Foster. It was made in both single-needle and two-needle forms which in operation were similar to the corresponding Cooke and Wheatstone instruments. The unique feature of this telegraph

6528-433: The two clicks. The message was then written out in long-hand. Royal Earl House developed and patented a letter-printing telegraph system in 1846 which employed an alphabetic keyboard for the transmitter and automatically printed the letters on paper at the receiver, and followed this up with a steam-powered version in 1852. Advocates of printing telegraphy said it would eliminate Morse operators' errors. The House machine

6624-402: The two needles energised were made to point to a letter of the alphabet. This allowed the apparatus to be used by unskilled operators without the need to learn a code – a key selling point to the railway companies the system was aimed at. Another advantage was that it was much faster at 30 characters per minute. It did not use heavy mercury as the damping fluid, but instead used a vane in air,

6720-743: The union changed its name to the American Communications Association and affiliated with the newly formed Congress of Industrial Organizations . A majority of the union's members were strongly left-wing , and most of the union's leaders were members of the Communist Party USA (CPUSA)—with the union effectively under the control of the CPUSA. In May-June 1951, the United States Senate Subcommittee on Internal Security (SSIS) held hearings on "Subversive Infiltration in

6816-416: The use of sound operators eliminated the need for telegraph receivers to include register and tape. Instead, the receiving instrument was developed into a "sounder", an electromagnet that was energized by a current and attracted a small iron lever. When the sounding key was opened or closed, the sounder lever struck an anvil. The Morse operator distinguished a dot and a dash by the short or long interval between

6912-479: Was French mathematician Pierre-Simon Laplace . On 2 October, André-Marie Ampère , acting on Laplace's suggestion, sent a paper on this idea to the Paris Academy of Sciences . Ampère's (theoretical) telegraph had a pair of wires for each letter of the alphabet with a keyboard to control which pair was connected to a battery. At the receiving end, Ampère placed small magnets (needles) under the wires. The effect on

7008-410: Was a five-needle, six-wire system, and had the major advantage of displaying the letter being sent so operators did not need to learn a code. The insulation failed on the underground cables between Paddington and West Drayton, and when the line was extended to Slough in 1843, the system was converted to a one-needle, two-wire configuration with uninsulated wires on poles. The cost of installing wires

7104-468: Was a substantial improvement on the Schilling telegraph. The needle instruments were based on the galvanometer of Macedonio Melloni . They were mounted on a vertical board with the needles centrally pivoted. The needles could be directly observed and Schilling's delicate silk threads were entirely done away with. The system required five wires, a slight reduction on that used by Schilling, partly because

7200-415: Was an early needle telegraph . It had a transmitting device that 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 silk threads . The two stations of Schilling's telegraph were connected by eight wires; six were connected with the galvanometers, one served for

7296-435: 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. His work was taken over and developed by Moritz von Jacobi who invented telegraph equipment that was used by Tsar Alexander III to connect

7392-520: Was considerably modified from the original American Morse code , and was based on a code used on Hamburg railways ( Gerke , 1848). A common code was a necessary step to allow direct telegraph connection between countries. With different codes, additional operators were required to translate and retransmit the message. In 1865, a conference in Paris adopted Gerke's code as the International Morse code and

7488-634: Was created in 1852 in Rochester, New York and eventually became the Western Union Telegraph Company . Although many countries had telegraph networks, there was no worldwide interconnection. Message by post was still the primary means of communication to countries outside Europe. Telegraphy was introduced in Central Asia during the 1870s. A continuing goal in telegraphy was to reduce the cost per message by reducing hand-work, or increasing

7584-513: Was eventually adopted. This was a two-needle system using two signal wires but displayed in a uniquely different way to other needle telegraphs. The needles made symbols similar to the Chappe optical system symbols, making it more familiar to the telegraph operators. The optical system was decommissioned starting in 1846, but not completely until 1855. In that year the Foy-Breguet system was replaced with

7680-665: Was far less limited than the momentary discharge of an electrostatic machine , which with Leyden jars were the only previously known human-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 1804 design by Spanish 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

7776-479: Was granted a patent on 4 July 1838. Davy also invented a printing telegraph which used the electric current from the telegraph signal to mark a ribbon of calico infused with potassium iodide and calcium hypochlorite . The first working telegraph was built by the English inventor Francis Ronalds in 1816 and used static electricity. At the family home on Hammersmith Mall , he set up a complete subterranean system in

7872-453: Was henceforth the international standard. The US, however, continued to use American Morse code internally for some time, hence international messages required retransmission in both directions. In the United States, the Morse/Vail telegraph was quickly deployed in the two decades following the first demonstration in 1844. The overland telegraph connected the west coast of the continent to

7968-427: Was implemented in Germany during the 1930s as a network used to communicate within the government. 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. Automatic teleprinter exchange service

8064-463: Was installed on the Euston to Camden Town section of Robert Stephenson 's London and Birmingham Railway in 1837 for signalling rope-hauling of locomotives. It was rejected in favour of pneumatic whistles. 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. This

8160-479: Was installing another system on the Nuremberg–Fürth railway line . Gauss suggested that he should use the rails as conductors and entirely avoid installing wires. This failed when Steinheil tried it because the rails were not well insulated from the ground, but in the process of this failure, he realised that he could use the ground as one of the conductors. This was the first earth-return telegraph put into service anywhere. The most widely used needle system, and

8256-537: Was intended for installation in Russia for government use, but Schilling died in 1837 before it could be implemented. Carl Friedrich Gauss and Wilhelm Eduard Weber built a telegraph that was used for scientific study and communication between university sites. Carl August von Steinheil adapted Gauss and Weber's rather cumbersome apparatus for use on various German railways. In England, William Fothergill Cooke started building telegraphs, initially based on Schilling's design. With Charles Wheatstone , Cooke produced

8352-399: 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. Needle telegraph A needle telegraph is an electrical telegraph that uses indicating needles moved electromagnetically as its means of displaying messages. It is one of the two main types of electromagnetic telegraph,

8448-617: Was invented by Alphonse Foy and Louis-François-Clement Breguet in 1842, and used in France. The instrument display was arranged to mimic the French optical telegraph system, with the two needles taking on the same positions as the arms of the Chappe semaphore (the optical system widely used in France). This arrangement meant that operators did not need to be retrained when their telegraph lines were upgraded to

8544-574: Was mooted by Gustav Theodor Fechner in Leipzig. Fechner, in other respects following the scheme of Ampère, also suggested a pair of wires for each letter (twenty-four in the German alphabet) laid underground to connect Leipzig with Dresden. Fechner's idea was taken up by William Ritchie of the Royal Institution of Great Britain in 1830. Ritchie used twenty-six pairs of wires run across a lecture room as

8640-435: Was nineteen-year-old Herbert Romerstein and retired Western Union employee and ex-ACA member Ann Graham Davis appeared, who claimed to have left ACA when forced to join the CPUSA. This article related to a North American labor union or trade union is a stub . You can help Misplaced Pages by expanding it . Electrical telegraph Electrical telegraphy is a point-to-point text messaging system, primarily used from

8736-438: Was rejected in favour of a system using steam whistles. Unsure of how far his telegraph could be made to work, Cooke consulted Michael Faraday and Peter Mark Roget . They put him in touch with eminent scientist Charles Wheatstone and the two then worked in partnership. Wheatstone suggested using a much improved needle instrument and they then developed a five-needle telegraph. The Cooke and Wheatstone five-needle telegraph

8832-406: Was that it did not require batteries. The telegraph pulses were generated by coils moving through a magnetic field as the operator worked the handles of the machine to send messages. The Henley-Foster instrument was the most sensitive instrument available in the 1850s. It could consequently be operated over a greater distance and worse quality lines than other systems. The Foy-Breguet telegraph

8928-469: 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 resulting systems were called "Telex" (TELegraph EXchange). Telex machines first performed rotary-telephone-style pulse dialling for circuit switching , and then sent data by ITA2 . This "type A" Telex routing functionally automated message routing. The first wide-coverage Telex network

9024-426: Was ultimately more economically significant than the cost of training operators. The one-needle telegraph proved highly successful on British railways, and 15,000 sets were in use at the end of the nineteenth century; some remained in service in the 1930s. The Electric Telegraph Company , the world's first public telegraphy company, was formed in 1845 by financier John Lewis Ricardo and Cooke. Wheatstone developed

9120-524: Was used on four main American telegraph lines by 1852. The speed of the House machine was announced as 2600 words an hour. 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

9216-670: Was very slow on the multi-needle telegraph, perhaps as low as four characters per minute , and even slower on the single-needle version. The reason for this was principally that Schilling had severely overdamped the movement of the needles by slowing them with a platinum paddle in a cup of mercury. Schilling's method of mounting the needle by suspending it by a silk thread over the multiplier also had practical difficulties. The instrument had to be carefully levelled before use and could not be moved or disturbed while in use. In 1833 Carl Friedrich Gauss and Wilhelm Eduard Weber set up an experimental needle telegraph between their laboratory in

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