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Lighthouse
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lens (optics), lenses and to serve as a beacon for navigational aid for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and the advent of much cheaper, more sophisticated, and more effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and promontory, prom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eddystone Lighthouse
The Eddystone Lighthouse is a lighthouse on the Eddystone Rocks, south of Rame Head in Cornwall, England. The rocks are submerged below the surface of the sea and are composed of Precambrian gneiss. View at 1:50000 scale The current structure is the fourth to be built on the site. The first lighthouse (Winstanley's) was swept away in a powerful storm, killing its architect and five other men in the process. The second (Rudyard's) stood for fifty years before it burned down. The third (Smeaton's) is renowned because of its influence on Lighthouse, lighthouse design and its importance in the development of concrete for building; its upper portions were re-erected in Plymouth as a monument. The first lighthouse, completed in 1699, was the world's first open ocean lighthouse, although the Cordouan Lighthouse off the western French coast preceded it as the first offshore lighthouse. The need for a light The Eddystone Rocks are an extensive reef approximately SSW off Plymouth S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse Of Alexandria
The Lighthouse of Alexandria, sometimes called the Pharos of Alexandria, was a lighthouse built by the Ptolemaic Kingdom of Ancient Egypt, during the reign of Ptolemy II Philadelphus (280–247 BC). It has been estimated to have been at least in overall height. One of the Seven Wonders of the Ancient World, for many centuries it was one of the tallest man-made structures in the world. The lighthouse was severely damaged by three earthquakes between 956 and 1303 AD and became an abandoned ruin. It was the third-longest surviving ancient wonder, after the Mausoleum at Halicarnassus and the extant Great Pyramid of Giza, surviving in part until 1480, when the last of its remnant stones were used to build the Citadel of Qaitbay on the site. In 1994, a team of French archaeologists dived in the water of Alexandria's Eastern Harbour and discovered some remains of the lighthouse on the sea floor. In 2016, the Ministry of State of Antiquities in Egypt had plans to turn submerged ruins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smeaton's Tower
Smeaton's Tower is a redundant lighthouse, now a memorial to civil engineer John Smeaton, designer of the third and most notable Eddystone Lighthouse#Smeaton.27s lighthouse, Eddystone Lighthouse. A major step forward in lighthouse design, Smeaton's structure was in use from 1759 to 1877, until erosion of the ledge it was built upon forced new construction. The tower was largely dismantled and rebuilt on Plymouth Hoe in Plymouth, Devon, where it stands today. History Background England’s coasts are notorious for rough weather, dangerous seas and deathly obstacles. The Eddystone rocks are among them. Several attempts were made to place a marker on these reefs. The first attempt was called the Winstanley Lighthouse. After it was destroyed in the 1703 storm, a second one called the Rudyard lighthouse was built. This one was also destroyed, this time by a fire in 1755. Born in Austhorpe, Yorkshire, England in 1724, John Smeaton is considered the father of civil engineering. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Smeaton
John Smeaton (8 June 1724 – 28 October 1792) was an English civil engineer responsible for the design of bridges, canals, harbours and lighthouses. He was also a capable mechanical engineer and an eminent scholar, who introduced various scientific method, scientific methodologies into engineering.Morris, Andrew M.A. (2021). "English engineer John Smeaton's experimental method(s)". Studies in History and Philosophy of Science, 89, 283-294, url=https://doi.org/10.1016/j.shpsa.2021.07.004 Smeaton was the first self-proclaimed "civil engineer", and is often regarded as the "father of civil engineering".Denny, Mark (2007). "Ingenium: Five Machines That Changed the World". p. 34. JHU Press. He pioneered the use of hydraulic lime in concrete, using pebbles and powdered brick as aggregate. Smeaton was associated with the Lunar Society. Law and physics Smeaton was born in Austhorpe, Leeds, England. After studying at Leeds Grammar School he joined his father's law firm, but left t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roman Rock Lighthouse
Roman Rock Lighthouse is a lighthouse in False Bay, near Simon's Town. It is the only lighthouse in South Africa built on a single rock. The light was first exhibited on 16 September 1861. The light was electrified in 1992 at the request of the South African Navy The South African Navy (SA Navy) is the naval warfare branch of the South African National Defence Force. The Navy is primarily engaged in maintaining a conventional military deterrent, participating in counter-piracy operations, fishery prote .... History Designed by Alexander Gordon of the British Lighthouse Authority, the lighthouse was a difficult endeavor due to the harsh conditions of the area, with fierce winds and turbulent seas, limited construction to a mere 96 working days annually, stretching the build over four-year. The original lighting mechanism was designed by James De Ville, a London-based lamp manufacturer, and consisted of a revolving platform that carried eight single-wick oil burners set in p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eddystone Rocks
The Eddystone or Eddystone Rocks are a seaswept and eroded group of rocks ranging southwest of Rame Head in Cornwall, England, United Kingdom. Although the nearest point on the mainland to the Eddystone is in Cornwall, the rocks fall within the city limits of Plymouth, and hence within the county of Devon. For centuries the rocks have been a hazard for the ships in the approaches to the English Channel and the port city of Plymouth. There have been four Eddystone Lighthouse, lighthouses on the Eddystone Rocks. Winstanley (two versions; the second replaced the top of the structure), Rudyard, Smeaton and finally the Douglass Lighthouse, which is the present one. When the Douglass Lighthouse was completed, the people of Plymouth paid for the dismantling of the Smeaton Lighthouse from the red rocks of Eddystone and its reassembly at Plymouth Hoe, where it is a popular Tourism, tourist attraction today. View at 1:50000 scale. The stub of the Smeaton lighthouse still remains on the roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandria
Alexandria ( ; ) is the List of cities and towns in Egypt#Largest cities, second largest city in Egypt and the List of coastal settlements of the Mediterranean Sea, largest city on the Mediterranean coast. It lies at the western edge of the Nile Delta, Nile River delta. Founded in 331 BC by Alexander the Great, Alexandria grew rapidly and became a major centre of Hellenic civilisation, eventually replacing Memphis, Egypt, Memphis, in present-day Greater Cairo, as Egypt's capital. Called the "Bride of the Mediterranean" and "Pearl of the Mediterranean Coast" internationally, Alexandria is a popular tourist destination and an important industrial centre due to its natural gas and petroleum, oil pipeline transport, pipelines from Suez. The city extends about along the northern coast of Egypt and is the largest city on the Mediterranean, the List of cities and towns in Egypt#Largest cities, second-largest in Egypt (after Cairo), the List of largest cities in the Arab world, fourth- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Winstanley
Henry Winstanley (31 March 1644 – 27 November 1703) was an English painter, engineer, and merchant who constructed the first Eddystone Lighthouse after losing two of his ships on the Eddystone rocks. He died while working on the project during the Great Storm of 1703. Early life and career He was born in Saffron Walden, Essex, and baptised there on 31 March 1644. His father, Henry, became land steward to the Earl of Suffolk, owner of Audley End House, in 1652, and young Henry also worked at Audley End, first as a porter and then as a secretary. In 1666, Audley End House was bought by Charles II for use as a base when attending Newmarket races, and it became effectively a royal palace. Winstanley developed an interest in engraving after a grand tour of Europe between 1669 and 1674, where he was impressed by Continental architecture and the engravings in which it was portrayed. On his return, he is believed to have studied engraving with Wenceslas Hollar and was employe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tower Of Hercules
The Tower of Hercules (, ) is the oldest known extant Roman lighthouse. Built in the 1st century, the tower is located on a peninsula about from the center of A Coruña, Galicia, in northwestern Spain. Until the 20th century, it was known as the Farum Brigantium. The :wiktionary:pharus#Latin, Latin word ''farum'' is derived from the Greek :wiktionary:Φάρος, Φάρος, ''Pharos'', for the Lighthouse of Alexandria. The structure stands tall and overlooks the North Atlantic coast of Spain. The tower was renovated in 1791. There is a sculpture garden on the grounds of the lighthouse featuring works by Pablo Serrano and . The Tower of Hercules is a National Monument (Spain), National Monument of Spain and has been a UNESCO World Heritage Sites in Spain, UNESCO World Heritage Site since 27 June 2009.UNESCO websiteof Hercules/ref> It is the second-tallest lighthouse in Spain, after the Chipiona Light, Faro de Chipiona. Construction and history The tower is known to have existed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Lime
Hydraulic lime (HL) is a general term for a variety of lime different from calcium oxide (quicklime), that sets by hydration and consists of calcium silicate and calcium aluminate, compounds that can harden in contact with water. This contrasts with calcium hydroxide, also called slaked lime or air lime that is used to make lime mortar, the other common type of lime mortar, which sets by carbonation (re-absorbing carbon dioxide (CO2) from the air). Hydraulic lime provides a faster initial set and higher compressive strength than air lime, and hydraulic lime will set in more extreme conditions, including under water. The terms 'hydraulic lime' and 'hydrated lime' are quite similar and may be confused but are not necessarily the same material. Hydrated lime is any lime which has been slaked whether it sets through hydration, carbonation, or both. Calcium reacts in the lime kiln with the clay minerals to produce silicates that enable some of the lime to set through hydration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigational Aid
A navigational aid (NAVAID), also known as aid to navigation (ATON), is any sort of signal, markers or guidance equipment which aids the traveler in navigation, usually nautical or aviation travel. Common types of such aids include lighthouses, buoys, fog signals, and day beacons. Definition According to the glossary of terms in the United States Coast Guard Light list, an ''aid to navigation'' (ATON) is any device external to a vessel or aircraft specifically intended to assist navigators in determining their position or safe course, or to warn them of dangers or obstructions to navigation. Lateral marks Lateral marks indicate the edge of the channel. The standards are defined by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). Approaching harbour port a vessel leaves port hand marks to port (left) and starboard hand marks to starboard (right). Port hand marks are cylindrical, starboard marks are conical. If the mark is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactured material in the world. When aggregate is mixed with dry Portland cement and water, the mixture forms a fluid slurry that can be poured and molded into shape. The cement reacts with the water through a process called hydration, which hardens it after several hours to form a solid matrix that binds the materials together into a durable stone-like material with various uses. This time allows concrete to not only be cast in forms, but also to have a variety of tooled processes performed. The hydration process is exothermic, which means that ambient temperature plays a significant role in how long it takes concrete to set. Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
