A tower is a tall structure, usually taller than it is wide, often by a significant margin. Towers are distinguished from masts by their lack of guy-wires.
Towers are generally built to take advantage of their height, and can stand alone on the ground, or as part of a larger structure or device such as a fortified building or as an integral part of a bridge, the term also denoting a raised structure on a ship or other vehicle.
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Towers have been used by mankind since prehistoric times. The oldest known may be the circular stone tower in walls of Neolithic Jericho (8000 BC). Some of the earliest towers were ziggurats, which existed in Sumerian architecture since the 4th millennium BC. The most famous ziggurats include the Sumerian Ziggurat of Ur, built the 3rd millennium BC, and the Etemenanki, one of the most famous examples of Babylonian architecture. The latter was built in Babylon during the 2nd millennium BC and was considered the tallest tower of the ancient world.
Some of the earliest surviving examples are the broch structures in northern Scotland, which are conical towerhouses. These and other examples from Phoenician and Roman cultures emphasised the use of a tower in fortification and sentinel roles. For example, watchtower elements are found at Mogador from the first millennium BC, derived from Phoenician or Carthaginian origins. The Romans utilised octagonal towers[1] as elements of Diocletian's Palace in Croatia, which monument dates to approximately 300 AD, while the Servian Walls (4th century BC) and the Aurelian Walls (3rd century AD) featured square ones. The Chinese used towers as integrated elements of the Great Wall of China in 210 BC during the Qin Dynasty. Towers were also an important element of castles.
Another well known tower is the Leaning Tower of Pisa in Pisa, Italy built from 1173 until 1372. The Himalayan Towers are stone towers located chiefly in Tibet built approximately 14th to 15th century. [2]
Old English torr is from Latin turris via Old French tor. The Latin term together with Greek τύρσις was loaned from a pre-Indo-European Mediterranean language, connected with the Illyrian toponym Βου-δοργίς. With the Lydian toponyms Τύρρα, Τύρσα, it has been connected with the ethnonym Τυρρήνιοι as well as with Tusci (from *Turs-ci), the Greek and Latin names for the Etruscans (Kretschmer Glotta 22, 110ff.) It may also be of Sanskrit derivation, from the word Sthavara meaning an unmovable entity.
Up to a certain height, a tower can be made with the supporting structure with parallel sides. However, above a certain height, the compressive load of the material is exceeded and the tower will fail. This can be avoided if the tower's support structure tapers up the building.
A second limit is that of buckling- the structure requires sufficient stiffness to avoid breaking under the loads it faces, especially those due to winds. Many very tall towers have their support structures at the periphery of the building, which greatly increases the overall stiffness.
A third limit is dynamic; a tower is subject to varying winds, vortex shedding, seismic disturbances etc. These are often dealt with a combination of simple strength and stiffness, as well as in some cases tuned mass dampers to damp out movements. Varying or tapering the outer aspect of the tower with height avoids vibrations due to vortex shedding occurring along the entire building simultaneously.
A modern type of tower, the skyscraper, uses less ground space as a ratio of total building interior square footage. Skyscrapers are often not classified as towers, although most have the same design and structure of towers. In the United Kingdom, tall domestic buildings are referred to as tower blocks. In the United States, the World Trade Center had the nickname the Twin Towers, a name shared with the Petronas Twin Towers in Kuala Lumpur. A tower has very deep foundations.
The tower throughout history has provided its users with an advantage in surveying defensive positions and obtaining a better view of the surrounding areas, including battlefields. They were installed on defensive walls, or rolled near a target (see siege tower). Today, strategic-use towers are still used at prisons, military camps, and defensive perimeters.
By using gravity to move objects or substances downward, a tower can be used to store items or liquids like a storage silo or a water tower, or aim an object into the earth such as a drilling tower. Ski-jump ramps use the same idea, and in the absence of a natural mountain slope or hill, can be human-made.
In history, simple towers like lighthouses, bell towers, clock towers, signal towers and minarets were used to communicate information over greater distances. In more recent years, radio masts and cell phone towers facilitate communication by expanding the range of the transmitter. The CN Tower in Toronto, Canada was built as a communications tower, with the capability to act as both a transmitter and repeater. Its design also incorporated features to make it a tourist attraction, including the world's highest observation deck at 147 stories.[citation needed]
Towers can also be used to support bridges, and can reach heights that rival some of the tallest buildings above-water. Their use is most prevalent in suspension bridges and cable-stayed bridges. The use of the pylon, a simple tower structure, has also helped to build railroad bridges, mass-transit systems, and harbors.
Control towers are used to give visibility to help direct aviation traffic.
The term "tower" is also sometimes used to refer to firefighting equipment with an extremely tall ladder designed for use in firefighting/rescue operations involving high-rise buildings.
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Albini is not credited in the liner notes, which read "Produced with eyes closed by Laura, who sat in the right chair." The reference is to Laura Ballance, the group's bassist.
Pocky is a popular Japanese snack food.
B-Sides include "Fishing", "Cool", "The Breadman", "It's So Hard to Fall in Love", "Brand New Love", and "I Believe in Fate".
Tower is the twenty-fifth album by the Finnish experimental rock band Circle. It was recorded in collaboration with Mika Rintala, who appears here under the alias Verde.
Members of Circle have been regular guests on Rintala's albums as Verde, often released on Jussi Lehtisalo's Ektro Records imprint. Here Rintala repays the favour on a collection of six keyboard-led instrumentals, occasionally reminiscent of Bitches Brew era Miles Davis. The tracks' names are the surname of a member of the group, including the sound engineer Tuomas Laurila, with the first letter replaced by a G.
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British Sea Power's Yan and Hamilton are brothers and were school friends with Wood in Kendal. They were in a number of bands together while at school, but after finishing his exams Yan moved to study at the University of Reading, where he met guitarist Noble, who was originally from Bury, Greater Manchester. A few years later, Hamilton and Wood joined them and formed a band.
The Youth Action Network (formerly the National Federation of Youth Action Agencies) was a UK-wide youth organisation that promotes volunteering by young people in their communities.
The organisation was set up in 1995 as a support network for Youth Action Agencies across the country. It was supported itself by the National Youth Agency, though this support ceased with the launch of Millennium Volunteers in 1999.
One of the chief successes of the organisation has been the development of a quality assurance model, based on PQASSO, for its members.
It merged into NCVYS on 9 March 2012
Youth Action Network members include:
Youth Action Network currently has around 100 member organisations which pay an annual fee to be a member of the network.
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The Terrapin served with the Royal Engineer assault teams of the 79th Armoured Division and were used to carry infantry units (Canadian and British) over rivers.
Due to a shortage of US-manufactured DUKWs, the British Ministry of Supply commissioned Thornycroft to design an amphibious vehicle capable of ferrying supplies and troops from ship to shore for the D-Day landings.
Some 500 Terrapin Mark 1 were built by Morris Commercial, the commercial vehicle side of Morris Motors Limited.
A Mark 2 Terrapin with a number of improvements reached the prototype stage, but the war ended before it entered production.
The Terrapin was powered by two Ford V8 engines mounted side-by-side with each motor driving the wheels on one side. Wheel braking was used to steer, the brakes being operated by levers.