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Daymark
A daymark is a navigational aid for sailors and pilots, distinctively marked to maximize its visibility in daylight. The word is also used in a more specific, technical sense to refer to a signboard or daytime identifier that is attached to a day beacon or other aid to navigation. In that sense, a daymark conveys to the mariner during daylight hours the same significance as does the aid's light or reflector at night. Standard signboard shapes are square, triangular and rectangular; and the standard colours are red, green, orange, yellow and black. Notable daymarks * Trinity House Obelisk * Kingswear Daymark *Tasku beacon tower *Keskiniemi beacon tower *Hiidenniemi beacon tower *Laitakari beacon tower *Herring Tower, Langness *Le Hocq *La Tour Cârrée *Scharhörnbake Symbols used on US charts Chart symbols used by the US National Oceanic and Atmospheric Administration Department, 2013. See also * Landmark * Sea mark * Lighthouse A lighthouse is a tower, buildin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingswear Daymark
Kingswear Daymark (also known as The Tower) is a 24 m (80 ft) octagonal limestone day beacon built in 1864, in an arable field above Froward Point near the town of Kingswear, Devon, England. Description The daymark was constructed of local limestone and slate in an arable field. It is octagonal and sharply battered with a truncated open top, and has a tall narrow pointed head arch on each side, forming eight stilted pillars. Construction In 1863, Charles Seale Hayne, owner of Brownstone at that time, became a founder member of the Dartmouth Harbour Commission whose main aim was to improve access and facilities to Dartmouth harbour. The following year, Seale Hayne leased land for the erection of this tower as a day beacon. See also *Day beacon *Landmark *Kingswear Kingswear is a village and civil parish in the South Hams area of the English county of Devon. The village is located on the east bank of the tidal River Dart, close to the river's mouth and opposite the small t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trinity House Obelisk
The Trinity House Obelisk, also known as the Trinity House Landmark, is a 19th-century obelisk located at Portland Bill, on the Isle of Portland, Dorset, England. Built as a daymark, it has been Grade II Listed since 1978. The obelisk was built in 1844 to warn ships off the coast of Portland Bill. It stands at the southern tip of the Isle of Portland, acting as a warning of the low shelf of rock extending 30 metres south into the sea. The obelisk is made of Portland stone Portland stone is a limestone from the Tithonian stage of the Jurassic period quarried on the Isle of Portland, Dorset. The quarries are cut in beds of white-grey limestone separated by chert beds. It has been used extensively as a building sto ... and is seven metres in height. It is inscribed "TH 1844" on its north face. The monument was saved from threatened demolition in 2002 after Trinity House deemed it too expensive to maintain. References {{Isle of Portland Isle of Portland Buildings and struc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Tour Cârrée
La Tour Cârrée, or The Square Tower, on Jersey, is not a tower but rather is a fortified guardhouse and magazine in the style of a blockhouse with loopholes for musketry. It may have been erected in 1778 on the site of a redoubt. The tower supported a battery of three 24-pounder cannons that stood on a paved surface in front of it. Shingle now covers this surface. The tower and battery played a role in the repelling in 1779 of the Prince of Nassau's attempt to land a force at the Franco-Dutch Invasion of Jersey. Historically, the structure and redoubts near it have been known as Square Fort, North Battery, and New North Battery. It is located on St Ouen's Bay, by St Ouen's Pond. Today the structure is painted white and black on the seaward side to serve as a daymark for sailors. Since 2007 the tower has been available as self-catering accommodation under a program the Jersey Heritage Trust administers for the States of Jersey Towers and Forts project. Accommodation is extremely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laitakari Beacon Tower
Laitakari beacon tower is a daymark (navigational aid) located on the island of Laitakari in the Gulf of Bothnia in Finland. The island is located east-northeast of Hailuoto and is within the municipal boundaries of the City of Oulu. There has been a navigational aid on the island since the 1750s, and a beacon tower has been marked on a chart dated in 1785. The current Laitakari beacon tower was built in 1851. The top of the tower is built of wooden boards and painted red. The top structure is resting on top of supporting wooden beams wedged into the gravel. The structure survived the Crimean War, and is still being used as a navigational aid. When aligned with the bell tower of Oulu Cathedral, it guides small vessels to the fairway leading past the northern coastline of Hailuoto Hailuoto (; sv, Karlö) is a Finnish island in the northern Baltic Sea and a municipality in Northern Ostrobothnia region. The population of Hailuoto is (), which make it the smallest municipality ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hiidenniemi Beacon Tower
Hiidenniemi beacon tower () was a historic daymark tower on the northern coast of Hailuoto island in Gulf of Bothnia in Finland. The structure was located at the northernmost point of the island, a minor promontory named Hiidenniemi. The structure was built in 1859 from the plans drawn by Ernst Lohrmann. It was a wooden hexagonal (six-sided) tower. The tower had a topmarker, which was either a weather vane or a simple flag A flag is a piece of fabric (most often rectangular or quadrilateral) with a distinctive design and colours. It is used as a symbol, a signalling device, or for decoration. The term ''flag'' is also used to refer to the graphic design empl .... The structure was later destroyed by fire and never rebuilt. Sources * {{Coord missing, Finland Towers completed in 1859 Towers in Finland Gulf of Bothnia Hailuoto Beacon towers Landmarks in Finland Buildings and structures in North Ostrobothnia Daymarks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keskiniemi Beacon Tower
The Keskiniemi beacon tower (''Keskiniemen tunnusmajakka'' in Finnish), often referred to as the Karvo beacon tower, is a historic daymark located on a promontory of Keskiniemi in the northwestern part of Hailuoto island in the Gulf of Bothnia in Finland Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B .... The tower was built in 1858 to alert the vessels about sandbars reaching northwest from the site. It is the oldest surviving navigational aid on Hailuoto island. The tower has structural similarities with the Härkmeri beacon tower built in 1857. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tasku Beacon Tower
Tasku beacon tower (''Taskun pooki'' in Finnish) is a daymark tower located on the island of Tasku (''Pocket'' in English) in the Raahe archipelago in the Gulf of Bothnia in Finland. The structure was built in 1853 from the plans drawn by Albin Stjerncreutz. In 1983 the Finnish Maritime Administration handed it over to the City of Raahe. Currently the city is responsible of the upkeep of this historical aid to navigation. The Tasku beacon tower is one of three historical beacon towers in Raahe archipelago, however only two beacon towers remain: the second one is the Iso-Kraaseli beacon tower. The tower is made of wood and supported by a wooden central column measuring 1.5 meters (5 feet) around. The tower consists of a square bottom section, followed by a pyramidical top section. The top marker is a wooden cross, rising 19.2 meters (63 feet) above sea level. The tower is painted yellow. The beacon tower has historical cultural heritage and is a part of Finnish maritime building he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Day Beacon
A day beacon (sometimes "daybeacon") is an unlighted nautical sea mark. A signboard identifying it is called a day mark. Day beacons typically mark channels whose key points are marked by lighted buoys. They may also mark smaller navigable routes in their entirety. They are the most common navigation aid in shallow water, as they are relatively inexpensive to install and maintain. Navigation around them is similar to that around other navigation aids. Identification Lateral marking For historical reasons, there are two systems for lateral day beacons. When proceeding from open water towards harbor, marks with cylindrical topmarks or square dayboards are kept to port in both regions, but colors and numbers are reversed. When lateral beacons are paired, vessels should pass between the pairing. However, beacons are also frequently placed individually. Generally, single lateral beacons are at the inside corner of a turn. Interior or exterior placement can be determined based up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Mark
A sea mark, also seamark and navigation mark, is a form of aid to navigation and pilotage that identifies the approximate position of a maritime channel, hazard, or administrative area to allow boats, ships, and seaplanes to navigate safely. There are three types of sea mark: beacons (fixed to the seabed or on shore), buoys (consisting of a floating object that is usually anchored to a specific location on the bottom of the sea or to a submerged object) and a type of cairn built on a submerged rock/object, especially in calmer waters. Sea marks are used to indicate channels, dangerous rocks or shoals, mooring positions, areas of speed limits, traffic separation schemes, submerged shipwrecks, and for a variety of other navigational purposes. Some are only intended to be visible in daylight ('' daymarks''), others have some combination of lights, reflectors, fog bells, foghorns, whistles and radar reflectors to make them usable at night and in conditions of reduced visibility ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retroreflector
A retroreflector (sometimes called a retroflector or cataphote) is a device or surface that reflects radiation (usually light) back to its source with minimum scattering. This works at a wide range of angle of incidence, unlike a planar mirror, which does this only if the mirror is exactly perpendicular to the wave front, having a zero angle of incidence. Being directed, the retroflector's reflection is brighter than that of a diffuse reflector. Corner reflectors and cat's eye reflectors are the most used kinds. Types There are several ways to obtain retroreflection: Corner reflector A set of three mutually perpendicular reflective surfaces, placed to form the internal corner of a cube, work as a retroreflector. The three corresponding normal vectors of the corner's sides form a basis in which to represent the direction of an arbitrary incoming ray, . When the ray reflects from the first side, say x, the ray's ''x''-component, ''a'', is reversed to −''a'', while the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Square Or Rectangular Daymark - Simplified Chart
In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90-degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length adjacent sides. It is the only regular polygon whose internal angle, central angle, and external angle are all equal (90°), and whose diagonals are all equal in length. A square with vertices ''ABCD'' would be denoted . Characterizations A convex quadrilateral is a square if and only if it is any one of the following: * A rectangle with two adjacent equal sides * A rhombus with a right vertex angle * A rhombus with all angles equal * A parallelogram with one right vertex angle and two adjacent equal sides * A quadrilateral with four equal sides and four right angles * A quadrilateral where the diagonals are equal, and are the perpendicular bisectors of each other (i.e., a rhombus with equal diagonals) * A convex quadrilateral with successiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landmark
A landmark is a recognizable natural or artificial feature used for navigation, a feature that stands out from its near environment and is often visible from long distances. In modern use, the term can also be applied to smaller structures or features, that have become local or national symbols. Etymology In old English the word ''landmearc'' (from ''land'' + ''mearc'' (mark)) was used to describe a boundary marker, an "object set up to mark the boundaries of a kingdom, estate, etc.". Starting from approx. 1560, this understanding of landmark was replaced by a more general one. A landmark became a "conspicuous object in a landscape". A ''landmark'' literally meant a geographic feature used by explorers and others to find their way back or through an area. For example, the Table Mountain near Cape Town, South Africa is used as the landmark to help sailors to navigate around southern tip of Africa during the Age of Exploration. Artificial structures are also sometimes built to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
