|
Menai Strait
The Menai Strait ( cy, Afon Menai, the "river Menai") is a narrow stretch of shallow tidal water about long, which separates the island of Anglesey from the mainland of Wales. It varies in width from from Fort Belan to Abermenai Point to from Traeth Gwyllt to Caernarfon Castle. It then narrows to in the middle reaches (Y Felinheli and Menai Bridge) and then it broadens again. At Bangor, Garth Pier, it is wide. It then widens out, and the distance from Puffin Island (Welsh: ''Ynys Seiriol'') to Penmaenmawr is about . The differential tides at the two ends of the strait cause very strong currents to flow in both directions through the strait at different times, creating dangerous conditions. One of the most dangerous areas of the strait is known as the Swellies (or Swillies – Welsh ''Pwll Ceris'') between the two bridges. Here, rocks near the surface cause over-falls and local whirlpools, which can be of considerable danger in themselves and cause small boats to founde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irish Sea
The Irish Sea or , gv, Y Keayn Yernagh, sco, Erse Sie, gd, Muir Èireann , Ulster-Scots: ''Airish Sea'', cy, Môr Iwerddon . is an extensive body of water that separates the islands of Ireland and Great Britain. It is linked to the Celtic Sea in the south by St George's Channel and to the Inner Seas off the West Coast of Scotland in the north by the North Channel. Anglesey, North Wales, is the largest island in the Irish Sea, followed by the Isle of Man. The term ''Manx Sea'' may occasionally be encountered ( cy, Môr Manaw, ga, Muir Meann gv, Mooir Vannin, gd, Muir Mhanainn). On its shoreline are Scotland to the north, England to the east, Wales to the southeast, Northern Ireland and the Republic of Ireland to the west. The Irish Sea is of significant economic importance to regional trade, shipping and transport, as well as fishing and power generation in the form of wind power and nuclear power plants. Annual traffic between Great Britain and Ireland amounts t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whirlpool
A whirlpool is a body of rotating water produced by opposing currents or a current running into an obstacle. Small whirlpools form when a bath or a sink is draining. More powerful ones formed in seas or oceans may be called maelstroms ( ). ''Vortex'' is the proper term for a whirlpool that has a downdraft. In narrow ocean straits with fast flowing water, whirlpools are often caused by tides. Many stories tell of ships being sucked into a maelstrom, although only smaller craft are actually in danger. Smaller whirlpools appear at river rapids and can be observed downstream of artificial structures such as weirs and dams. Large cataracts, such as Niagara Falls, produce strong whirlpools. Notable whirlpools Saltstraumen Saltstraumen is a narrow strait located close to the Arctic Circle, south-east of the city of Bodø, Norway. It has one of the strongest tidal currents in the world. Whirlpools up to in diameter and in depth are formed when the current is at its strongest. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ynys Gorad Goch
Ynys Gored Goch ("Red Weir Island"), sometimes Ynys Gorad Goch, is a small island in the Menai Strait between Gwynedd and Anglesey in north Wales. It is situated in the stretch of the strait called the Swellies between Thomas Telford's Menai Suspension Bridge and Robert Stephenson's Britannia Bridge. The island is occupied by the main house and the converted smoke house where locally caught fish were processed. The island is private property and access is only by boat. History The earliest known document relating to the island dates from 1590 when it is listed as belonging to the Diocese of Bangor which leased it for £3 and a barrel of herrings a year Hughes, Margaret: ''Anglesey from the Sea'', page 14. Carreg Gwalch, 2001 as the island was used as a fishing trap and presently has the remains of two fishing weirs. The weirs are thought to have been constructed at the same time as the smoking chamber was built, around 1842, in the path of eddy currents that would take the fish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A55 Road
The A55, also known as the North Wales Expressway ( cy, Gwibffordd Gogledd Cymru) is a major road in Wales and England, connecting Cheshire and north Wales. The vast majority of its length from Chester to Holyhead is a dual carriageway primary route, with the exception of the Britannia Bridge over the Menai Strait and several short sections where there are gaps in between the two carriageways. All junctions are grade separated apart from a roundabout east of Penmaenmawr and another nearby in Llanfairfechan. Initially, the road ran from Chester to Bangor. In 2001, it was extended across Anglesey to the ferry port of Holyhead parallel to the A5. The road improvements have been part funded with European money, under the Trans-European Networks programme, as the route is designated part of Euroroute E22 ( Holyhead – Leeds – Amsterdam – Hamburg – Malmö – Riga – Moscow – Perm – Ekaterinburg – Ishim). Route The Chester southerly bypass The A55 begins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Box Girder Bridge
A box girder bridge, or box section bridge, is a bridge in which the main beams comprise girders in the shape of a hollow box. The box girder normally comprises prestressed concrete, structural steel, or a composite of steel and reinforced concrete. The box is typically rectangular or trapezoidal in cross-section. Box girder bridges are commonly used for highway flyovers and for modern elevated structures of light rail transport. Although the box girder bridge is normally a form of beam bridge, box girders may also be used on cable-stayed and other bridges. Development of steel box girders In 1919, Major Gifford Martel was appointed head of the Experimental Bridging Establishment at Christchurch, Hampshire, which researched the possibilities of using tanks for battlefield engineering purposes such as bridge-laying and mine-clearing. Here he continued trials on modified Mark V tanks. The bridging component involved an assault bridge, designed by Major Charles Ingli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wrought-iron
Wrought iron is an iron alloy with a very low carbon content (less than 0.08%) in contrast to that of cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which give it a wood-like "grain" that is visible when it is etched, rusted, or bent to failure. Wrought iron is tough, malleable, ductile, corrosion resistant, and easily forge welded, but is more difficult to weld electrically. Before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. It was given the name ''wrought'' because it was hammered, rolled, or otherwise worked while hot enough to expel molten slag. The modern functional equivalent of wrought iron is mild steel, also called low-carbon steel. Neither wrought iron nor mild steel contain enough carbon to be hardenable by heating and quenching. Wrought iron is highly refined, with a small amount of silicate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Britannia Bridge
Britannia Bridge ( cy, Pont Britannia) is a bridge across the Menai Strait between the island of Anglesey and the mainland of Wales. It was originally designed and built by the noted railway engineer Robert Stephenson as a tubular bridge of wrought iron rectangular box-section spans for carrying rail traffic. Its importance was to form a critical link of the Chester and Holyhead Railway's route, enabling trains to directly travel between London and the port of Holyhead, thus facilitating a sea link to Dublin, Ireland. Decades before the building of the Britannia Bridge, the Menai Suspension Bridge had been completed, but this structure carried a road rather than track; there was no rail connection to Anglesey before its construction. After many years of deliberation and proposals, on 30 June 1845, a Parliamentary Bill covering the construction of the Britannia Bridge received royal assent. At the Admiralty's insistence, the bridge elements were required to be relatively high ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Stephenson
Robert Stephenson Fellow of the Royal Society, FRS HFRSE FRSA Doctor of Civil Law, DCL (16 October 1803 – 12 October 1859) was an English civil engineer and designer of locomotives. The only son of George Stephenson, the "Father of Railways", he built on the achievements of his father. Robert has been called the greatest engineer of the 19th century. Life Robert was born in Willington Quay near Wallsend, Northumberland, the son of George Stephenson and his wife, Frances Henderson. The family moved to Killingworth, where Robert was taught at the local village school. Robert attended the middle-class Percy Street Academy in Newcastle and at the age of fifteen was apprenticed to the mining engineer Nicholas Wood. He left before he had completed his three years to help his father survey the Stockton and Darlington Railway. Robert spent six months at Edinburgh University before working for three years as a mining engineer in Colombia. When he returned his father was building t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A5 Road (Great Britain)
The A5 (commonly known as the London-Holyhead Trunk Road) is a major road in England and Wales. It runs for about from London to the Irish Sea at the ferry port of Holyhead. In many parts the route follows that of the Roman Iter II route which later took the Anglo-Saxon name Watling Street. History Roman Road The section of the A5 between London and Shrewsbury is roughly contiguous with one of the principal Roman roads in Britain: that between ''Londinium'' and ''Deva'', which diverges from the present-day A5 corridor at Wroxeter (''Viroconium Cornoviorum'') near Shrewsbury. Telford's Holyhead Road The Act of Union 1800, which unified Great Britain and Ireland, gave rise to a need to improve communication links between London and Dublin. A parliamentary committee led to an Act of Parliament of 1815 that authorised the purchase of existing turnpike road interests and, where necessary, the construction of new road, to complete the route between the two capitals. This made i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Menai Suspension Bridge
The Menai Suspension Bridge ( cy, Pont y Borth, Pont Grog y Borth) is a suspension bridge spanning the Menai Strait between the island of Anglesey and the mainland of Wales. Designed by Thomas Telford and completed in 1826, it was the world's first major suspension bridge. The bridge still carries road traffic and is a Grade I listed structure. Background The Menai Strait was created by glacial erosion along a line of weakness associated with the Menai Strait Fault System. During a series of Pleistocene glaciations (that lasted from about 2,580,000 to 11,700 years ago), a succession of ice-sheets moved from northeast to southwest across Anglesey and neighbouring Gwynedd, scouring the underlying rock and creating a series of linear bedrock hollows. The deepest of these channels eventually became flooded by the sea as the ice sheets receded, forming the Menai Strait. As Anglesey has been an island throughout recorded human history, the only way to reach it was by crossing the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American War Of Independence
The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, was a major war of the American Revolution. Widely considered as the war that secured the independence of the United States, fighting began on April 19, 1775, followed by the Lee Resolution on July 2, 1776, and the Declaration of Independence on July 4, 1776. The American Patriots were supported by the Kingdom of France and, to a lesser extent, the Dutch Republic and the Spanish Empire, in a conflict taking place in North America, the Caribbean, and the Atlantic Ocean. Established by royal charter in the 17th and 18th centuries, the American colonies were largely autonomous in domestic affairs and commercially prosperous, trading with Britain and its Caribbean colonies, as well as other European powers via their Caribbean entrepôts. After British victory over the French in the Seven Years' War in 1763, tensions between the motherland and her ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
