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Bureau Des Longitudes
__NOTOC__ The ''Bureau des Longitudes'' () is a French scientific institution, founded by decree of 25 June 1795 and charged with the improvement of nautical navigation, standardisation of time-keeping, geodesy and astronomical observation. During the 19th century, it was responsible for synchronizing clocks across the world. It was headed during this time by François Arago and Henri Poincaré. The Bureau now functions as an academy and still meets monthly to discuss topics related to astronomy. The Bureau was founded by the National Convention after it heard a report drawn up jointly by the Committee of Navy, the Committee of Finances and the Committee of State education. Henri Grégoire had brought to the attention of the National Convention France's failing maritime power and the naval mastery of England, proposing that improvements in navigation would lay the foundations for a renaissance in naval strength. As a result, the Bureau was established with authority over the P ...
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Navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the motion, movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, marine navigation, air navigation, aeronautic navigation, and space navigation. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks. All navigational techniques involve locating the navigator's Position (geometry), position compared to known locations or patterns. Navigation, in a broader sense, can refer to any skill or study that involves the determination of position and Relative direction, direction. In this sense, navigation includes orienteering and pedestrian navigation. For marine navigation, this involves the safe movement of ships, boats and other nautical craft either on or underneath the water using positions from navigation equipment with appropriate nautical char ...
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Pierre-Simon Laplace
Pierre-Simon, Marquis de Laplace (; ; 23 March 1749 – 5 March 1827) was a French polymath, a scholar whose work has been instrumental in the fields of physics, astronomy, mathematics, engineering, statistics, and philosophy. He summarized and extended the work of his predecessors in his five-volume Traité de mécanique céleste, ''Mécanique céleste'' (''Celestial Mechanics'') (1799–1825). This work translated the geometric study of classical mechanics to one based on calculus, opening up a broader range of problems. Laplace also popularized and further confirmed Isaac Newton, Sir Isaac Newton's work. In statistics, the Bayesian probability, Bayesian interpretation of probability was developed mainly by Laplace. Laplace formulated Laplace's equation, and pioneered the Laplace transform which appears in many branches of mathematical physics, a field that he took a leading role in forming. The Laplace operator, Laplacian differential operator, widely used in mathematic ...
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Hour
An hour (symbol: h; also abbreviated hr) is a unit of time historically reckoned as of a day and defined contemporarily as exactly 3,600 seconds ( SI). There are 60 minutes in an hour, and 24 hours in a day. The hour was initially established in the ancient Near East as a variable measure of of the night or daytime. Such seasonal hours, also known as temporal hours or unequal hours, varied by season and latitude. Equal hours or equinoctial hours were taken as of the day as measured from noon to noon; the minor seasonal variations of this unit were eventually smoothed by making it of the mean solar day. Since this unit was not constant due to long term variations in the Earth's rotation, the hour was finally separated from the Earth's rotation and defined in terms of the atomic or physical second. It is a non-SI unit that is accepted for use with SI. In the modern metric system, one hour is defined as 3,600 atomic seconds. However, on rare occasions an hour may inc ...
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Colony
A colony is a territory subject to a form of foreign rule, which rules the territory and its indigenous peoples separated from the foreign rulers, the colonizer, and their ''metropole'' (or "mother country"). This separated rule was often organized into colonial empires, with their metropoles at their centers, making colonies neither annexation, annexed or even Territorial integration, integrated territories, nor client states. Particularly new imperialism and its colonialism advanced this separated rule and its lasting coloniality. Colonies were most often set up and colonized for exploitation and possibly settlement by colonists. The term colony originates from the ancient rome, ancient Roman , a type of Roman settlement. Derived from ''colonus'' (farmer, cultivator, planter, or settler), it carries with it the sense of 'farm' and 'landed estate'. Furthermore, the term was used to refer to the older Greek ''apoikia'' (), which were Greek colonisation, overseas settlements by ...
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French Colonial Empire
The French colonial empire () comprised the overseas Colony, colonies, protectorates, and League of Nations mandate, mandate territories that came under French rule from the 16th century onward. A distinction is generally made between the "First French colonial empire", that existed until 1814, by which time most of it had been lost or sold, and the "Second French colonial empire", which began with the French conquest of Algeria, conquest of Algiers in 1830. On the eve of World War I, France's colonial empire was List of largest empires, the second-largest in the world after the British Empire. France began to establish colonies in the French colonization of the Americas, Americas, the Caribbean, and French India, India in the 16th century but lost most of its possessions after its defeat in the Seven Years' War. The North American possessions were lost to Britain and Spain, but Louisiana (New France), Spain later returned Louisiana to France in 1800. The territory was then Loui ...
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Pneumatic Tubes
Pneumatics (from Greek 'wind, breath') is the use of gas or pressurized air in mechanical systems. Pneumatic systems used in industry are commonly powered by compressed air or compressed inert gases. A centrally located and electrically-powered compressor powers cylinders, air motors, pneumatic actuators, and other pneumatic devices. A pneumatic system controlled through manual or automatic solenoid valves is selected when it provides a lower cost, more flexible, or safer alternative to electric motors, and hydraulic actuators. Pneumatics also has applications in dentistry, construction, mining, and other areas. History Although the early history of pneumatics is somewhat unclear, blowguns are often considered the earliest pneumatic device, being created independently by various indigenous groups around the world. Bellows are an early form of air compressor used primarily for smelting and forging. Ctesibius of Alexandria is often considered the father of pneumatics, "wh ...
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Telescopes
A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects – an optical telescope. Nowadays, the word "telescope" is defined as a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in t ...
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Manufacturer
Manufacturing is the creation or Production (economics), production of goods with the help of equipment, Work (human activity), labor, machines, tools, and chemical or biological processing or formulation. It is the essence of the secondary sector of the economy. The term may refer to a range of Human behavior, human activity, from handicraft to High tech manufacturing, high-tech, but it is most commonly applied to industrial design, in which raw materials from the primary sector of the economy, primary sector are transformed into finished goods on a large scale. Such goods may be sold to other manufacturers for the production of other more complex products (such as aircraft, Major appliance, household appliances, furniture, sports equipment or automobiles), or distributed via the tertiary industry to end users and consumers (usually through wholesalers, who in turn sell to retailers, who then sell them to individual customers). Manufacturing engineering is the field of engine ...
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Louis Antoine De Bougainville
Louis-Antoine, Comte de Bougainville (; 12 November 1729 – 31 August 1811) was a French military officer and explorer. A contemporary of the British explorer James Cook, he served in the Seven Years' War and the American Revolutionary War. Bougainville later gained fame for his expeditions, including a circumnavigation of the globe in a scientific expedition in 1763, the first recorded settlement on the Falkland Islands, and voyages into the Pacific Ocean. Bougainville Island of Papua New Guinea as well as the flowering plant '' Bougainvillea'' are named in his honour. Biography Early career Bougainville was born in Paris, the capital of the Kingdom of France, the son of notary Pierre-Yves de Bougainville (1688–1756), on 12 November 1729. In early life, he studied law, but soon abandoned the profession. In 1753, he entered the French Army in the corps of Musketeers of the Guard. At the age of twenty-five he published a treatise on integral calculus, as a supplement to G ...
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Geographer
A geographer is a physical scientist, social scientist or humanist whose area of study is geography, the study of Earth's natural environment and human society, including how society and nature interacts. The Greek prefix "geo" means "earth" and the Greek suffix, "graphy", meaning "description", so a geographer is someone who studies the earth. The word "geography" is a Middle French word that is believed to have been first used in 1540. Although geographers are historically known as people who make maps, map making is actually the field of study of cartography, a subset of geography. Geographers do not study only the details of the natural environment or human society, but they also study the reciprocal relationship between these two. For example, they study how the natural environment contributes to human society and how human society affects the natural environment. In particular, physical geographers study the natural environment while human geographers study human society ...
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Jean-Charles De Borda
Jean-Charles, chevalier de Borda (4 May 1733 – 19 February 1799) was a French mathematician, physicist, and Navy officer. Biography Borda was born in the city of Dax to Jean‐Antoine de Borda and Jeanne‐Marie Thérèse de Lacroix. In 1756, Borda wrote ''Mémoire sur le mouvement des projectiles'', a product of his work as a military engineer. For that, he was elected to the French Academy of Sciences in 1764. Borda was a mariner and a scientist, spending time in the Caribbean testing out advances in chronometers. Between 1777 and 1778, he participated in the American Revolutionary War. In 1781, he was put in charge of several vessels in the French Navy. In 1782, he was captured by the English, and was returned to France shortly after. He returned as an engineer in the French Navy, making improvements to waterwheels and pumps. He was appointed as France's Inspector of Naval Shipbuilding in 1784, and with the assistance of the naval architect Jacques-Noël Sané in ...
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Dominique, Comte De Cassini
Jean-Dominique, comte de Cassini (30 June 174818 October 1845), also called Cassini IV, was a French astronomer, son of César-François Cassini de Thury and great-grandson of Giovanni Domenico Cassini. Cassini was born at the Paris Observatory. He succeeded his father as director of the observatory in 1784; but his plans for its restoration and re-equipment were wrecked in 1793 by the animosity of the National Assembly of France, National Assembly. His position having become intolerable, he resigned on 6 September and was thrown into prison in 1794, but released after seven months. He then withdrew to Thury, where he died in 1845. In 1770, he published an account of a voyage to America in 1768, undertaken as the commissary of the French Academy of Sciences with a view to testing Pierre Le Roy’s watches at sea. In 1783, his father César-François Cassini de Thury had sent a letter to the Royal Society in London, in which he proposed a Trigonometry, trigonometric survey con ...
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