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Foy–Breguet Telegraph
The Foy–Breguet telegraph, also called the French telegraph, was an electrical telegraph of the needle telegraph type developed by Louis-François-Clement Breguet and Alphonse Foy in the 1840s for use in France. The system used two-needle instruments that presented a display using the same code as that on the optical telegraph of Claude Chappe. The Chappe telegraph was extensively used in France by the government, so this arrangement was appealing to them as it meant there was no need to retrain operators. Most needle telegraph systems moved the needles by means of an electromagnet driven by battery power applied to the line at the sending end. In contrast, the Foy-Breguet telegraph used electromagnets but they did not directly drive the needle. Instead, they operated the detent of a clockwork mechanism which released the needle to move on one position at a time. The Chappe telegraph existed in some other countries, but no country besides France tried to duplicate the Cha ...
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Cooke And Wheatstone Telegraph
The Cooke and Wheatstone telegraph was an early electrical telegraph system dating from the 1830s invented by English inventor William Fothergill Cooke and English scientist Charles Wheatstone. It was a form of needle telegraph, and the first telegraph system to be put into commercial service. The receiver consisted of a number of needles that could be moved by electromagnetic coils to point to letters on a board. This feature was liked by early users who were unwilling to learn codes, and employers who did not want to invest in staff training. In later systems, the letter board was dispensed with, and the code was read directly from the movement of the needles. This occurred because the number of needles was reduced, leading to more complex codes. The change was motivated by the economic need to reduce the number of telegraph wires used, which was related to the number of needles. The change became more urgent as the insulation of some of the early installations deteriorat ...
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Backward Compatibility
In telecommunications and computing, backward compatibility (or backwards compatibility) is a property of an operating system, software, real-world product, or technology that allows for interoperability with an older legacy system, or with Input/output, input designed for such a system. Modifying a system in a way that does not allow backward compatibility is sometimes called "wikt:breaking change, breaking" backward compatibility. Such breaking usually incurs various types of costs, such as Switching barriers, switching cost. A complementary concept is ''forward compatibility''; a design that is forward-compatible usually has a Technology roadmap, roadmap for compatibility with future standards and products. Usage In hardware A simple example of both backward and forward compatibility is the introduction of FM broadcasting, FM radio in stereophonic sound, stereo. FM radio was initially monaural, mono, with only one audio channel represented by one signal (electrical engineerin ...
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Abraham Niclas Edelcrantz
Abraham Niclas Edelcrantz (born Clewberg; 28 July 1754 – 15 March 1821) was a Finnish-born Swedish poet and inventor. He was a member of the Swedish Academy, chair 2, from 1786 to 1821. Edelcrantz was the librarian at The Royal Academy of Turku. In 1783 he moved to Stockholm to lead the Royal Theater and later work as the private secretary of the king Gustaf III.National Museum of Science and Technology, Sweden
He is known for his experiment with the optical telegraph. He inaugurated his telegraph with a poem dedicated to the Swedish King on his birthday in 1794. The message went from the Palace in Stockholm to the King at Drottningholm.
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Napoleon
Napoleon Bonaparte (born Napoleone di Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French general and statesman who rose to prominence during the French Revolution and led Military career of Napoleon, a series of military campaigns across Europe during the French Revolutionary and Napoleonic Wars from 1796 to 1815. He led the French First Republic, French Republic as French Consulate, First Consul from 1799 to 1804, then ruled the First French Empire, French Empire as Emperor of the French from 1804 to 1814, and briefly again in 1815. He was King of Italy, King of Kingdom of Italy (Napoleonic), Italy from 1805 to 1814 and Protector of the Confederation of the Rhine, Protector of the Confederation of the Rhine from 1806 to 1813. Born on the island of Corsica to a family of Italian origin, Napoleon moved to mainland France in 1779 and was commissioned as an officer in the French Royal Army in 1785. He supported the French Rev ...
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Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ...
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Codepoint
A code point, codepoint or code position is a particular position in a table, where the position has been assigned a meaning. The table may be one dimensional (a column), two dimensional (like cells in a spreadsheet), three dimensional (sheets in a workbook), etc... in any number of dimensions. Technically, a code point is a unique position in a quantized n-dimensional space, where the position has been assigned a semantic meaning. The table has discrete (whole) and positive positions (1, 2, 3, 4, but not fractions). Code points are used in a multitude of formal information processing and telecommunication standards.ETSI TS 101 773 (section 4), https://www.etsi.org/deliver/etsi_ts/101700_101799/101773/01.02.01_60/ts_101773v010201p.pdf For example ITU-T Recommendation T.35 contains a set of country codes for telecommunications equipment (originally fax machines) which allow equipment to indicate its country of manufacture or operation. In T.35, Argentina is represented by the code ...
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Codebook
A codebook is a type of document used for gathering and storing cryptography codes. Originally, codebooks were often literally , but today "codebook" is a byword for the complete record of a series of codes, regardless of physical format. Cryptography In cryptography, a codebook is a document used for implementing a code. A codebook contains a lookup table for coding and decoding; each word or phrase has one or more strings which replace it. To decipher messages written in code, corresponding copies of the codebook must be available at either end. The distribution and physical security of codebooks presents a special difficulty in the use of codes compared to the secret information used in ciphers, the key, which is typically much shorter. The United States National Security Agency documents sometimes use ''codebook'' to refer to block ciphers; compare their use of ''combiner-type algorithm'' to refer to stream ciphers. Codebooks come in two forms, one-part or two-part: * ...
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Watchmaker
A watchmaker is an artisan who makes and repairs watches. Since a majority of watches are now factory-made, most modern watchmakers only repair watches. However, originally they were master craftsmen who built watches, including all their parts, by hand. Modern watchmakers, when required to repair older watches, for which replacement parts may not be available, must have fabrication skills, and can typically manufacture replacements for many of the parts found in a watch. The term clockmaker refers to an equivalent occupation specializing in clocks. Most practising professional watchmakers service current or recent production watches. They seldom fabricate replacement parts. Instead they obtain and fit factory spare parts applicable to the watch brand being serviced. The majority of modern watchmakers, particularly in Switzerland and other countries in Europe, work directly for the watchmaking industry and may have completed a formal watchmaking degree at a technical school ...
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Abraham-Louis Breguet
Abraham-Louis Breguet (; 10 January 1747 – 17 September 1823), born in Neuchâtel, then a Prussian principality, was a Swiss-French horologist who made many innovations in the course of a career in watchmaking industry, including the tourbillon. He was the founder of the Breguet company, which is now a luxury watch division of the Swiss Swatch Group. In his lifetime he was considered the leading watchmaker of his day, and he built up a clientele that included many leading public figures and members of the European nobility. Alongside his friend and contemporary John Arnold, Breguet is now widely acknowledged as one of the greatest horologists of all time. One of his famous ancestors was Jean Breguet (who died in 1593) a Protestant pastor in Neuchâtel very much influenced by the ideas of John Calvin. Life Breguet was born in Neuchâtel to Jonas-Louis Breguet and Suzanne-Marguerite Bolle. Breguet's father died in 1758 when he was ten, and his formal schooling ende ...
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Code Point
A code point, codepoint or code position is a particular position in a Table (database), table, where the position has been assigned a meaning. The table may be one dimensional (a column), two dimensional (like cells in a spreadsheet), three dimensional (sheets in a workbook), etc... in any number of dimensions. Technically, a code point is a unique position in a quantized n-dimensional space, where the position has been assigned a semantic meaning. The table has discrete (whole) and positive positions (1, 2, 3, 4, but not fractions). Code points are used in a multitude of formal information processing and telecommunication standards.ETSI TS 101 773 (section 4), https://www.etsi.org/deliver/etsi_ts/101700_101799/101773/01.02.01_60/ts_101773v010201p.pdf For example ITU-T Recommendation T.35 contains a set of country codes for telecommunications equipment (originally fax machines) which allow equipment to indicate its country of manufacture or operation. In T.35, Argentina is repre ...
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Rouen
Rouen (, ; or ) is a city on the River Seine, in northwestern France. It is in the prefecture of Regions of France, region of Normandy (administrative region), Normandy and the Departments of France, department of Seine-Maritime. Formerly one of the largest and most prosperous cities of medieval Europe, the population of the metropolitan area () is 702,945 (2018). People from Rouen are known as ''Rouennais''. Rouen was the seat of the Exchequer of Normandy during the Middle Ages. It was one of the capitals of the Anglo-Normans, Anglo-Norman and Angevin kings of England, Angevin dynasties, which ruled both England and large parts of modern France from the 11th to the 15th centuries. From the 13th century onwards, the city experienced a remarkable economic boom, thanks in particular to the development of textile factories and river trade. Claimed by both the French and the English during the Hundred Years' War, it was on its soil that Joan of Arc was tried and burned alive on 30 ...
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