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Big Ben

This article is about the famous bell in London and the clock of which it forms part; for other uses see Big Ben (disambiguation)

Big Ben, more formally the Great Bell of Westminster, is the hour bell of the Great Clock of Westminster, hanging in the Clock Tower of the Palace of Westminster, the home of the Houses of Parliament in the United Kingdom.

One theory says that the bell was named "Big Ben" after Sir Benjamin Hall, the Chief Commissioner of Works. Another theory suggests that at the time anything which was heaviest of its kind was called "Big Ben" after the then-famous prizefighter Benjamin Caunt , making it a natural name for the bell.

Big Ben is commonly taken to be the name of the clock tower itself, but this is incorrect - the tower is simply known as The Clock Tower. Sometimes, the tower is referred to as St. Stephen's Tower, but this title is not used by staff of the Palace of Westminster.

The bell weighs 13.762 tonnes (13 long tons 10 cwt 99 lb or 30,339 lb), with a striking hammer weighing 203 kg (4 cwt), and was originally tuned to E. There is delay of 5 seconds between strikes. It is a common misconception that Big Ben is the heaviest bell in Britain. In fact, it is only the third heaviest, the second heaviest being Great George found at Liverpool Cathedral at 14 tons 15 cwt 2 qtr 2 lb (33,098 lb or 15.013 Mg) and the heaviest being Great Paul found at St Paul's Cathedral at 16 tons 14 cwt 2 qtr 19 lb (37483 lb or 17.002 t).

The original tower designs demanded a 14 long ton (14 t) bell to be struck with a 6 cwt (300 kg) hammer. A bell was produced by John Warner and Sons in 1856, weighing 16 tons (long or metric). However, this cracked under test in the Palace Yard. The contract for the bell was then given to the Whitechapel Bell Foundry, who in 1858 re-cast the bell into the 13.8 t bell used today. It too started to crack under the 6 cwt (300 kg) hammer, and a legal battle arose. After two years of having the Great Bell out of commission, the 6 cwt (300 kg) hammer was replaced with a lighter 4 cwt (200 kg) hammer, and the bell itself was turned 90 degrees so the crack would not develop any further, coming back into use in 1862. However, the crack, now filled, and the turn meant that it no longer struck a true E.

The belfry also houses four quarter bells which play the Westminster Chimes, derived from Handel's Messiah, on the quarter hours. The C note in the chime is repeated twice in quick succession, faster than the chiming train can draw back the hammers, so the C bell uses two separate hammers.

Reliability


The clock is famous for its reliability. This is due to its designer, the lawyer and amateur horologist Edmund Beckett Denison, later Lord Grimthorpe. As the clock mechanism, created to Denison's specification by clockmaker Edward John Dent , was completed before the tower itself was finished, Denison had time to experiment with the clock. Instead of using the deadbeat escapement and remontoire as originally designed, Denison invented the double three legged gravity escapement . This escapement provides the best separation between pendulum and clock mechanism. Together with an enclosed, wind-proof box sunk beneath the clockroom, the Great Clock's pendulum is well isolated from external factors like snow, ice and pigeons on the clock hands, and keeps remarkably accurate time.

The clock had its first and only major breakdown in 1976. The chiming mechanism broke due to metal fatigue on August 5th, 1976, and was reactivated again on May 9. During this time BBC Radio Four had to make do with the pips.

The idiom of putting a penny on, with the meaning of slowing down, sprung from the method of fine-tuning the clock's pendulum by adding or subtracting penny-coins. Even to this day, only old pennies, phased out of British currency during the 1971 decimalisation, are used.

A 20-foot (6 m) metal replica of the clock tower known as Little Ben, complete with working clock, stands on a traffic island close to Victoria Station. Several turret clocks around the world are inspired by the look of the Great Clock, including the clock tower of the Gare de Lyon in Paris and the Peace Tower of the Parliament of Canada in Ottawa.

Culture

The Clock Tower - which contains Big Ben - , London
Enlarge
The Clock Tower - which contains Big Ben - Palace of Westminster, London

Big Ben is a focus of New Year celebrations in the UK, with radio and TV stations tuning to its chimes to welcome the 'official' start of the year. Similarly, on Remembrance Day, the chimes of Big Ben are broadcast to mark the 11th hour of the 11th day of the 11th month and the start of two minutes silence.

For many years ITN's "News at Ten" began with an opening sequence which featured Big Ben with the chimes punctuating the announcement of the news headlines. This has since been dropped, but all ITV1 and ITV News Channel bulletins still use a graphic based on the Westminster clock face. Big Ben can also be heard striking the hour before some news bulletins on BBC Radio 4 and the BBC World Service, a practice that began on December 31, 1923.

The clock features in John Buchan's spy novel The Thirty-Nine Steps and makes for a memorable climax in Don Sharp 's 1978 film version, although not in Alfred Hitchcock's 1935 original adaptation. A similar scene is recreated in the 2003 film, Shanghai Knights which culminates with Jackie Chan hanging from the hands of the clock. The clock also features in the climax of the animated film Basil, the Great Mouse Detective.

An earlier film climax on the clock face of Big Ben appears in Will Hay's 1943 film My Learned Friend, although the scene is more slapstick than thriller.

External links

07-10-2008 09:35:13
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