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Trispastos
A treadwheel crane () is a wooden, human powered hoisting and lowering device. It was primarily used during the Roman period and the Middle Ages in the building of castles and cathedrals. The often heavy charge is lifted as the individual inside the treadwheel crane walks. History Ancient Rome The Roman ''polyspaston'' crane, from Ancient Greek πολύσπαστον (polúspaston, “compound pulley”), when worked by four men at both sides of the winch, could lift 3000 kg. In case the winch has been replaced by a treadwheel, the maximum load even doubled to 6000 kg at only half the crew, since the treadwheel possesses a much bigger mechanical advantage due to its larger diameter. This meant that, in comparison to the construction of the ancient Egyptian pyramids, where about 50 men were needed to move a 2.5 ton stone block up the ramp (50 kg per person), the lifting capability of the Roman ''Polyspaston'' proved to be ''60 times'' more efficient (3000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crane (machine)
A crane is a machine used to move materials both vertically and horizontally, utilizing a system of a boom, hoist, wire ropes or chains, and sheaves for lifting and relocating heavy objects within the swing of its boom. The device uses one or more simple machines, such as the lever and pulley, to create mechanical advantage to do its work. Cranes are commonly employed in transportation for the loading and unloading of freight, in construction for the movement of materials, and in manufacturing for the assembling of heavy equipment. The first known crane machine was the shaduf, a water-lifting device that was invented in ancient Mesopotamia (modern Iraq) and then appeared in ancient Egyptian technology. Construction cranes later appeared in ancient Greece, where they were powered by men or animals (such as donkeys), and used for the construction of buildings. Larger cranes were later developed in the Roman Empire, employing the use of human treadwheels, permitting the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trestle Support
In structural engineering, a trestle support (or simply trestle) is a structural element with rigid Beam (structure), beams forming the equal sides of two parallel isosceles triangles, joined at their Apex (geometry), apices by a Plank (wood), plank or beam. Sometimes additional rungs are stretched between the two beams. A pair of trestle legs can support one or several boards or planks, forming a trestle table or trestle desk. A network of trestle supports can serve as the framework for a trestle bridge, and a trestle of appropriate size to hold wood for sawing is known as a sawhorse. Trestle table A trestle table is a table with trestle legs. In shape and manufacture, it sometimes resembles variations of the antique field desk, which were used by officers close to the battlefield. Trestle legs come in two kinds: *Fixed trestle legs, where the angle between the legs is a fixed joint. *Folding trestle legs, where the angle is hinged, to make them more compact and portable. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England
England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It shares Anglo-Scottish border, a land border with Scotland to the north and England–Wales border, another land border with Wales to the west, and is otherwise surrounded by the North Sea to the east, the English Channel to the south, the Celtic Sea to the south-west, and the Irish Sea to the west. Continental Europe lies to the south-east, and Ireland to the west. At the 2021 United Kingdom census, 2021 census, the population was 56,490,048. London is both List of urban areas in the United Kingdom, the largest city and the Capital city, capital. The area now called England was first inhabited by modern humans during the Upper Paleolithic. It takes its name from the Angles (tribe), Angles, a Germanic peoples, Germanic tribe who settled du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamburg
Hamburg (, ; ), officially the Free and Hanseatic City of Hamburg,. is the List of cities in Germany by population, second-largest city in Germany after Berlin and List of cities in the European Union by population within city limits, 7th-largest in the European Union with a population of over 1.9 million. The Hamburg Metropolitan Region has a population of over 5.1 million and is the List of EU metropolitan areas by GDP, eighth-largest metropolitan region by GDP in the European Union. At the southern tip of the Jutland Peninsula, Hamburg stands on the branching River Elbe at the head of a estuary to the North Sea, on the mouth of the Alster and Bille (Elbe), Bille. Hamburg is one of Germany's three city-states alongside Berlin and Bremen (state), Bremen, and is surrounded by Schleswig-Holstein to the north and Lower Saxony to the south. The Port of Hamburg is Germany's largest and Europe's List of busiest ports in Europe, third-largest, after Port of Rotterdam, Rotterda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bruges
Bruges ( , ; ; ) is the capital and largest city of the province of West Flanders, in the Flemish Region of Belgium. It is in the northwest of the country, and is the sixth most populous city in the country. The area of the whole city amounts to more than 14,099 hectares (140.99 km2; 54.44 sq. miles), including 1,075 hectares off the coast, at Zeebrugge (from , meaning 'Bruges by the Sea'). The historic city center is a prominent World Heritage Site of UNESCO. It is oval and about 430 hectares in size. The city's total population is 117,073 (1 January 2008),Statistics Belgium; ''Population de droit par commune au 1 janvier 2008'' (excel-file) Population of all municipalities in Belgium, as of 1 January 2008. Retrieved on 19 October 2008. of who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antwerp
Antwerp (; ; ) is a City status in Belgium, city and a Municipalities of Belgium, municipality in the Flemish Region of Belgium. It is the capital and largest city of Antwerp Province, and the third-largest city in Belgium by area at , after Tournai and Couvin. With a population of 565,039, it is the List of most populous municipalities in Belgium, most populous municipality in Belgium, and with a metropolitan population of over 1.2 million people, the country's Metropolitan areas in Belgium, second-largest metropolitan area after Brussels. Definitions of metropolitan areas in Belgium. Flowing through Antwerp is the river Scheldt. Antwerp is linked to the North Sea by the river's Western Scheldt, Westerschelde estuary. It is about north of Brussels, and about south of the Netherlands, Dutch border. The Port of Antwerp is one of the biggest in the world, ranking second in Europe after Rotterdam and List of world's busiest container ports, within the top 20 globally. The city ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utrecht (city)
Utrecht ( ; ; ) is the List of cities in the Netherlands by province, fourth-largest city of the Netherlands, as well as the capital and the most populous city of the Provinces of the Netherlands, province of Utrecht (province), Utrecht. The municipality of Utrecht is located in the eastern part of the Randstad conurbation, in the very centre of mainland Netherlands, and includes Haarzuilens, Vleuten and De Meern. It has a population of 376,435 as of . Utrecht's ancient city centre features many buildings and structures, several dating as far back as the High Middle Ages. It has been the religious centre of the Netherlands since the 8th century. In 1579, the Union of Utrecht was signed in the city to lay the foundations for the Dutch Republic. Utrecht was the most important city in the Netherlands until the Dutch Golden Age, when it was surpassed by Amsterdam as the country's cultural centre and most populous city. Utrecht is home to Utrecht University, the largest university ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manuscript
A manuscript (abbreviated MS for singular and MSS for plural) was, traditionally, any document written by hand or typewritten, as opposed to mechanically printed or reproduced in some indirect or automated way. More recently, the term has come to be understood to further include ''any'' written, typed, or word-processed copy of an author's work, as distinguished from the rendition as a printed version of the same. Before the arrival of prints, all documents and books were manuscripts. Manuscripts are not defined by their contents, which may combine writing with mathematical calculations, maps, music notation, explanatory figures, or illustrations. Terminology The word "manuscript" derives from the (from , hand and from , to write), and is first recorded in English in 1597. An earlier term in English that shares the meaning of a handwritten document is "hand-writ" (or "handwrit"), which is first attested around 1175 and is now rarely used. The study of the writing ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlantic, North Atlantic, the French West Indies, and List of islands of France, many islands in Oceania and the Indian Ocean, giving it Exclusive economic zone of France, one of the largest discontiguous exclusive economic zones in the world. Metropolitan France shares borders with Belgium and Luxembourg to the north; Germany to the northeast; Switzerland to the east; Italy and Monaco to the southeast; Andorra and Spain to the south; and a maritime border with the United Kingdom to the northwest. Its metropolitan area extends from the Rhine to the Atlantic Ocean and from the Mediterranean Sea to the English Channel and the North Sea. Its Regions of France, eighteen integral regions—five of which are overseas—span a combined area of and hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Roman Empire
In modern historiography, the Western Roman Empire was the western provinces of the Roman Empire, collectively, during any period in which they were administered separately from the eastern provinces by a separate, independent imperial court. Particularly during the period from AD 395 to 476, there were separate, coequal courts dividing the governance of the empire into the Western provinces and the Eastern provinces with a distinct Line of hereditary succession, imperial succession in the separate courts. The terms Western Roman Empire and Byzantine Empire, Eastern Roman Empire were coined in modern times to describe political entities that were ''de facto'' independent; contemporary Ancient Rome, Romans did not consider the Empire to have been split into two empires but viewed it as a single polity governed by two imperial courts for administrative expediency. The Western Empire collapsed in 476, and the Western imperial court in Ravenna disappeared by AD 554, at the end of Ju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
