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Old Hunstanton Lighthouse
Old Hunstanton Lighthouse is a former lighthouse located in Old Hunstanton in the English county of Norfolk,Ordnance Survey (2002). ''OS Explorer Map 250 - Norfolk Coast West''. . generally called Hunstanton Lighthouse (or, less formally, 'Hunston Lighthouse') during its operational life. It was built at the highest point available on this part of the coast, on top of Hunstanton Cliffs, and served to help guide vessels into the safe water of Lynn Deeps. Although the present lighthouse was built in 1840, there had been a lighthouse on the site since the 17th century (prior to which a light to aid navigation may have been displayed from St Edmund's Chapel, the ruins of which stand nearby). Prior to the establishment of the Lynn Well light vessel in 1828, Hunstanton Lighthouse provided the only visible guide to ships seeking to enter The Wash at night. History Before the establishment of a lighthouse in the vicinity, it appears that sailors used the lights burning in St Edmund's Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norfolk
Norfolk () is a ceremonial and non-metropolitan county in East Anglia in England. It borders Lincolnshire to the north-west, Cambridgeshire to the west and south-west, and Suffolk to the south. Its northern and eastern boundaries are the North Sea, with The Wash to the north-west. The county town is the city of Norwich. With an area of and a population of 859,400, Norfolk is a largely rural county with a population density of 401 per square mile (155 per km2). Of the county's population, 40% live in four major built up areas: Norwich (213,000), Great Yarmouth (63,000), King's Lynn (46,000) and Thetford (25,000). The Broads is a network of rivers and lakes in the east of the county, extending south into Suffolk. The area is protected by the Broads Authority and has similar status to a national park. History The area that was to become Norfolk was settled in pre-Roman times, (there were Palaeolithic settlers as early as 950,000 years ago) with camps along the highe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabolic Reflector
A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis. The parabolic reflector transforms an incoming plane wave travelling along the axis into a spherical wave converging toward the focus. Conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis. Parabolic reflectors are used to collect energy from a distant source (for example sound waves or incoming star light). Since the principles of reflection are reversible, parabolic reflectors can also be used to collimate radiation from an isotropic source into a parallel beam. In optics, parabolic mirrors are used to gather light in reflecting telescopes and solar furnaces, and project a beam of light in flas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sector Light
A sector light is a man-made pilotage and position fixing aid that consists of strictly delineated horizontal angle light beams to guide water-borne traffic through a safe channel at night in reasonable visibility. Sector lights are most often used for safe passage through shallow or dangerous waters. This may be when leaving or entering harbour. Nautical charts (paper and electronic) give all the required information. Sectors of colored glass (or plastic) are placed in the lanterns of these lights. The light will then show these colors when observed certain bearings. Bearings referring to a sector are given in degrees true, as observed from sea. Though the colors of the light will change, the characteristics will not. The change of color is not abrupt. The transition is made through an arc of uncertainty of 2° or greater. The colors that are used, are conform to the IALA Maritime Buoyage system that is designed by the International Association of Lighthouse Authorities: * whit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newcastle-upon-Tyne
Newcastle upon Tyne ( RP: , ), or simply Newcastle, is a city and metropolitan borough in Tyne and Wear, England. The city is located on the River Tyne's northern bank and forms the largest part of the Tyneside built-up area. Newcastle is also the most populous city of North East England. Newcastle developed around a Roman settlement called Pons Aelius and the settlement later took the name of a castle built in 1080 by William the Conqueror's eldest son, Robert Curthose. Historically, the city’s economy was dependent on its port and in particular, its status as one of the world's largest ship building and repair centres. Today, the city's economy is diverse with major economic output in science, finance, retail, education, tourism, and nightlife. Newcastle is one of the UK Core Cities, as well as part of the Eurocities network. Famous landmarks in Newcastle include the Tyne Bridge; the Swing Bridge; Newcastle Castle; St Thomas’ Church; Grainger Town including Grey's M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cookson Group
Vesuvius plc is a British engineered ceramics company headquartered in London whose products are used by steelmakers and foundries as well as in the glass and solar energy industries. The company is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index. History The company was founded by Isaac Cookson in 1704 as a collection of metal and glass businesses on Tyneside. In 1851 the Company diversified into lead manufacturing. In 1924 it merged with ''Lock Lancaster'' and ''W.W. & R. Johnson & Sons'' to form ''Associated Lead Manufacturers''. It was first listed on the London Stock Exchange in 1930.Cookson Group History In 1966 it was renamed ''Lead Industries Group'' and in 1979 it acquired the ''A.J. Oster Company'', a non-ferrous metal producer. In 1982 it changed its name again to ''Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresnel Lens
A Fresnel lens ( ; ; or ) is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships." The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. The simpler dioptric (purely refractive) form of the lens was first proposed by Count Buffon and independently reinvented by Fresnel. The ''catadioptric'' form of the lens, entirely invented by Fresnel, has outer elements that use total internal reflection as well as refraction; it can capture more oblique light from a light source and add it to the beam of a lighthouse, making the light visible from greater distances. Description The Fresnel lens redu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catadioptric
A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses (dioptrics) and curved mirrors (catoptrics). Catadioptric combinations are used in focusing systems such as searchlights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto lenses. Other optical systems that use lenses and mirrors are also referred to as "catadioptric", such as surveillance catadioptric sensors. Early catadioptric systems Catadioptric combinations have been used for many early optical systems. In the 1820s, Augustin-Jean Fresnel developed several catadioptric lighthouse reflectors. Léon Foucault developed a catadioptric microscope in 1859 to counteract aberrations of using a lens to image objects at high power. In 1876 a French engineer, A. Mangin, invented what has come to be called the Mangin mirror, a concave glass reflector with the silver surface on the rear side of the glass. The two surfaces o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second Order Fresnel Lens
A Fresnel lens ( ; ; or ) is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships." The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. The simpler dioptric (purely refractive) form of the lens was first proposed by Count Buffon and independently reinvented by Fresnel. The ''catadioptric'' form of the lens, entirely invented by Fresnel, has outer elements that use total internal reflection as well as refraction; it can capture more oblique light from a light source and add it to the beam of a lighthouse, making the light visible from greater distances. Description The Fresnel lens red ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Walker (engineer)
James Walker (14 September 1781 – 8 October 1862) was an influential British civil engineer. Life Born in Law Wynd in Falkirk, the eldest of five children of John Walker and his wife Margaret, James was educated at the local school and was sent to Glasgow University in October 1794, aged 13. He studied Latin and Greek for two years, and logic during his third year. During his final two years he studied natural philosophy and mathematics, taking the first prize. He returned to Falkirk in May 1799, aged 18, and his family discussed a career in business or law. But, by chance, in the summer of 1800, he was asked to accompany his ill brother-in-law on a sea journey to London. Once there, he visited his uncle Ralph Walker in Blackwall, intending to return to Scotland after a week. However, Ralph discussed his work at the West India Docks, and was so impressed by his young nephew's grasp of engineering that he immediately took him on as his apprentice. Around 1800 they worked o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corporation Of Trinity House
"Three In One" , formation = , founding_location = Deptford, London, England , status = Royal Charter corporation and registered charity , purpose = Maintenance of lighthouses, buoys and beacons , headquarters = Trinity House, Tower Hill, London, England , region = , membership = , leader_title = Master , leader_name = Anne, Princess Royal , leader_title2 = Deputy Master , leader_name2 = Captain Ian McNaught , revenue = £38,405,000 (2020) , expenses = £46,801,000 (2020) , staff = 312 (2020) , website trinityhouse.co.uk The Corporation of Trinity House of Deptford Strond, also known as Trinity House (and formally as The Master, Wardens and Assistants of the Guild Fraternity or Brotherhood of the most glorious and undivided Trinity and of St Clement in the Parish of Deptford Strond in the County of Kent), is the of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
League (unit)
A league is a unit of length. It was common in Europe and Latin America, but is no longer an official unit in any nation. Derived from an ancient Celtic unit and adopted by the Romans as the ''leuga'', the league became a common unit of measurement throughout western Europe. It may have originally represented, roughly, the distance a person could walk in an hour. Since the Middle Ages, many values have been specified in several countries. Different definitions Ancient Rome The league was used in Ancient Rome, defined as 1½ Roman miles (7,500 Roman feet, modern 2.2 km or 1.4 miles). The origin is the ''leuga Gallica'' ''(also: leuca Callica)'', the league of Gaul. Argentina The Argentine league (''legua'') is or 6,666 ''varas'': 1 ''vara'' is . English-speaking world On land, the league is most commonly defined as three miles (4.83km), though the length of a mile could vary from place to place and depending on the era. At sea, a league is . English usage also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North By East
The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each separated by 90 degrees, and secondarily divided by four ordinal (intercardinal) directions—northeast, southeast, southwest, and northwest—each located halfway between two cardinal directions. Some disciplines such as meteorology and navigation further divide the compass with additional azimuths. Within European tradition, a fully defined compass has 32 'points' (and any finer subdivisions are described in fractions of points). Compass points are valuable in that they allow a user to refer to a specific azimuth in a colloquial fashion, without having to compute or remember degrees. Designations The names of the compass point directions follow these rules: 8-wind compass rose * The four cardinal directions are north (N), east (E), s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
