Big Ben



Big Ben is the nickname for the Great Bell of the clock at the north end of the Palace of Westminster in London and is usually extended to refer to both the clock and the clock tower as well. The tower is officially known as Elizabeth Tower, renamed to celebrate the Diamond Jubilee of Elizabeth II in 2012; previously, it was known simply as the Clock Tower. When completed in 1859, it was, says clockmaker Ian Westworth, “the prince of timekeepers: the biggest, most accurate four-faced striking and chiming clock in the world.” The tower had its 150th anniversary on 31 May 2009, during which celebratory events took place.

A British cultural icon, the tower is one of the most prominent symbols of the United Kingdom and is often in the establishing shot of films set in London.

Tower


The Elizabeth Tower (previously called the Clock Tower), more popularly known as Big Ben, was raised as a part of Charles Barry's design for a new palace, after the old Palace of Westminster was largely destroyed by fire on the night of 16 October 1834. The new parliament was built in a neo-gothic style. Although Barry was the chief architect of the palace, he turned to Augustus Pugin for the design of the clock tower, which resembles earlier Pugin designs, including one for Scarisbrick Hall in Lancashire. The design for the tower was Pugin's last design before his final descent into madness and death, and Pugin himself wrote, at the time of Barry's last visit to him to collect the drawings: "I never worked so hard in my life for Mr Barry for tomorrow I render all the designs for finishing his bell tower & it is beautiful." The tower is designed in Pugin's celebrated Gothic Revival style, and is 315 ft high.



The bottom 200 ft of the tower's structure consists of brickwork with sand-coloured Anston limestone cladding. The remainder of the tower's height is a framed spire of cast iron. The tower is founded on a 50 ft square raft, made of 10 ft thick concrete, at a depth of 13 ft below ground level. The four clock dials are 180 ft above ground. The interior volume of the tower is 164,200 cubic feet (4,650 cubic metres).

Despite being one of the world's most famous tourist attractions, the interior of the tower is not open to overseas visitors, though United Kingdom residents are able to arrange tours (well in advance) through their Member of Parliament. However, the tower currently has no lift, though one is planned, so those escorted must climb the 334 limestone stairs to the top.

Due to changes in ground conditions since construction, the tower leans slightly to the north-west, by roughly 230 mm over 55 m height, giving an inclination of approximately 1/240. This includes a planned maximum of 22 mm increased tilt due to tunnelling for the Jubilee line extension. Due to thermal effects it oscillates annually by a few millimetres east and west.

Journalists during Queen Victoria's reign called it St Stephen's Tower. As MPs originally sat at St Stephen's Hall, these journalists referred to anything related to the House of Commons as news from "St. Stephens" (the Palace of Westminster contains a feature called St Stephen's Tower, a smaller tower over the public entrance). The usage persists in Welsh, where the Westminster district, and Parliament by extension, is known as San Steffan.

On 2 June 2012, The Daily Telegraph reported that 331 Members of Parliament, including senior members of all three main parties, supported a proposal to change the name from Clock Tower to Elizabeth Tower in tribute to Queen Elizabeth II in her diamond jubilee year. This was thought to be appropriate because the large west tower now known as Victoria Tower was renamed in tribute to Queen Victoria on her diamond jubilee. On 26 June 2012, the House of Commons confirmed that the name change could go ahead. The Prime Minister, David Cameron, announced the change of name on 12 September 2012 at the start of Prime Minister's Questions. The change was marked by a naming ceremony in which the Speaker of the House of Commons, John Bercow, unveiled a name plaque attached to the tower on the adjoining Speaker's Green.

Dials


The clock and dials were designed by Augustus Pugin. The clock dials are set in an iron frame 23 ft in diameter, supporting 312 pieces of opal glass, rather like a stained-glass window. Some of the glass pieces may be removed for inspection of the hands. The surround of the dials is gilded. At the base of each clock dial in gilt letters is the Latin inscription:

"DOMINE SALVAM FAC REGINAM NOSTRAM VICTORIAM PRIMAM"

Which means O Lord, keep safe our Queen Victoria the First.

Unlike most other Roman numeral clock dials, which show the '4' position as 'IIII', the Great Clock faces depict '4' as 'IV'.

Movement


The clock's movement is famous for its reliability. The designers were the lawyer and amateur horologist Edmund Beckett Denison, and George Airy, the Astronomer Royal. Construction was entrusted to clockmaker Edward John Dent; after his death in 1853 his stepson Frederick Dent completed the work, in 1854. As the tower was not complete until 1859, Denison had time to experiment: 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. The pendulum is installed within an enclosed windproof box beneath the clockroom. It is 13 ft long, weighs 300 kg, suspended on a strip of spring steel 1/64 inch in thickness, and beats every 2 seconds. The clockwork mechanism in a room below weighs 5 tons. On top of the pendulum is a small stack of old penny coins; these are to adjust the time of the clock. Adding a coin has the effect of minutely lifting the position of the pendulum's centre of mass, reducing the effective length of the pendulum rod and hence increasing the rate at which the pendulum swings. Adding or removing a penny will change the clock's speed by 0.4 seconds per day.

On 10 May 1941, a German bombing raid damaged two of the clock's dials and sections of the tower's stepped roof and destroyed the House of Commons chamber. Architect Sir Giles Gilbert Scott designed a new five-floor block. Two floors are occupied by the current chamber, which was used for the first time on 26 October 1950. The clock ran accurately and chimed throughout the Blitz.

Malfunctions, breakdowns, and other interruptions in operation



 * 1916: For two years during World War I, the bells were silenced and the clock faces were not illuminated at night to avoid guiding attacking German Zeppelins.
 * 1 September 1939: Although the bells continued to ring, the clock faces were not illuminated at night through World War II to avoid guiding bomber pilots during the Blitz.
 * 3–4 June 1941: The clock stopped from 10:13 p.m. until 10:13 the following morning, after a workman repairing air raid damage to the clock face dropped a hammer into the works.
 * 1949: The clock slowed by four and a half minutes after a flock of starlings perched on the minute hand.
 * New Year's Eve 1962: The clock slowed due to heavy snow and ice on the long hands, causing the pendulum to detach from the clockwork, as it is designed to do in such circumstances, to avoid serious damage elsewhere in the mechanism – the pendulum continuing to swing freely. Thus it chimed in the new year 10 minutes late.
 * 30 January 1965: The bells were silenced during the funeral of statesman and Prime Minister Winston Churchill.
 * 5 August 1976: First and only major breakdown. The air brake speed regulator of the chiming mechanism broke from torsional fatigue after more than 100 years of use, causing the fully wound 4-ton weight to spin the winding drum out of the movement, causing much damage. The Great Clock was shut down for a total of 26 days over nine months – it was reactivated on 9 May 1977; this was the longest break in operation since its construction. During this time BBC Radio 4 broadcast the pips instead. Although there were minor stoppages from 1977 to 2002 when maintenance of the clock was carried out by the old firm of clockmakers Thwaites & Reed, these were often repaired within the permitted two-hour downtime and not recorded as stoppages. Prior to 1970 maintenance was carried out by the original firm of Dents, and since 2002 by parliamentary staff.
 * 30 April 1997: The clock stopped 24 hours before the general election, and stopped again three weeks later.
 * 27 May 2005: The clock stopped at 10:07 p.m., possibly because of hot weather; temperatures in London had reached an unseasonable 31.8 °C (90 °F). It resumed, but stopped again at 10:20 p.m. and remained still for about 90 minutes before resuming.
 * 29 October 2005: The mechanism was stopped for about 33 hours to allow maintenance work on the clock and its chimes. It was the lengthiest maintenance shutdown in 22 years.
 * 7:00 a.m. 5 June 2006: The clock tower's "Quarter Bells" were taken out of commission for four weeks as a bearing holding one of the quarter bells was worn and needed to be removed for repairs. During this period, BBC Radio 4 broadcast recordings of British bird song followed by the pips in place of the usual chimes.
 * 11 August 2007: Start of 6-week stoppage for maintenance. Bearings in the clock's chime train and the "great bell" striker were replaced, for the first time since installation. During the maintenance works the clock was driven by an electric motor. Once again, BBC Radio 4 broadcast the pips during this time. The intention is that the clock should run accurately for a further 200 years before major maintenance is again required.
 * 17 April 2013: The bells were silenced as a mark of "profound dignity and deep respect" during the funeral of Margaret Thatcher.
 * August 2015: The clock was discovered to be running 7 seconds fast, and coins were removed from its pendulum to correct the error, which caused it to run slow for a time.

Great Bell


The main bell, officially known as the Great Bell but better known as Big Ben, is the largest bell in the tower and part of the Great Clock of Westminster.

The original bell was a 16 ton (16.3-tonne) hour bell, cast on 6 August 1856 in Stockton-on-Tees by John Warner & Sons. The bell was possibly named in honour of Sir Benjamin Hall, and his name is inscribed on it. However, another theory for the origin of the name is that the bell may have been named after a contemporary heavyweight boxer Benjamin Caunt. It is thought that the bell was originally to be called Victoria or Royal Victoria in honour of Queen Victoria, but that an MP suggested the nickname during a Parliamentary debate; the comment is not recorded in Hansard.

Since the tower was not yet finished, the bell was mounted in New Palace Yard. The first bell was transported to the tower on a trolley drawn by sixteen horses, with crowds cheering its progress. During the bell's testing, it cracked beyond repair and a replacement had to be made. The bell was recast on 10 April 1858 at the Whitechapel Bell Foundry as a 13½ ton (13.76-tonne) bell. This was pulled 200 ft up to the Clock Tower’s belfry, a feat that took 18 hours. It is 7 ft tall and 9 ft diameter. This new bell first chimed in July 1859; in September it too cracked under the hammer. According to the foundry's manager, George Mears, the horologist Denison had used a hammer more than twice the maximum weight specified. For three years Big Ben was taken out of commission and the hours were struck on the lowest of the quarter bells until it was repaired. To make the repair, a square piece of metal was chipped out from the rim around the crack, and the bell given an eighth of a turn so the new hammer struck in a different place. Big Ben has chimed with a slightly different tone ever since, and is still in use today with the crack unrepaired. Big Ben was the largest bell in the British Isles until "Great Paul", a 16¾ ton (17 tonne) bell currently hung in St Paul's Cathedral, was cast in 1881.

Chimes


Along with the Great Bell, the belfry houses four quarter bells which play the Westminster Quarters on the quarter hours. The four quarter bells sound G♯, F♯, E, and B. They were cast by John Warner & Sons at their Crescent Foundry in 1857 (G♯, F♯ and B) and 1858 (E). The Foundry was in Jewin Crescent, in what is now known as The Barbican, in the City of London.

The quarter bells play a once-repeating, 20-note sequence of rounds and four changes in the key of E major: 1–4 at quarter past, 5–12 at half past, 13–20 and 1–4 at quarter to, and 5–20 on the hour (which sounds 25 seconds before the main bell tolls the hour). Because the low bell (B) is struck twice in quick succession, there is not enough time to pull a hammer back, and it is supplied with two wrench hammers on opposite sides of the bell. The tune is that of the Cambridge Chimes, first used for the chimes of Great St Mary's church, Cambridge, and supposedly a variation, attributed to William Crotch, based on violin phrases from the air "I know that my Redeemer liveth" in Handel's Messiah. The notional words of the chime, again derived from Great St Mary's and in turn an allusion to Psalm 37:23–24, are: "All through this hour/Lord be my guide/And by Thy power/No foot shall slide". They are written on a plaque on the wall of the clock room.

One of the requirements for the clock was that the first stroke of the hour bell should be correct to within one second per day. The tolerance is with reference to Greenwich Mean Time (BST in summer). So, at twelve o'clock, for example, it is the first of the twelve hour-bell strikes that signifies the hour (the New Year on New Year's Day at midnight). The time signalled by the last of the "six pips" (UTC) may be fractionally different.

Nickname
The origin of the nickname Big Ben is the subject of some debate. The nickname was applied first to the Great Bell; it may have been named after Sir Benjamin Hall, who oversaw the installation of the Great Bell, or after boxing's English heavyweight champion Benjamin Caunt. Now Big Ben is often used, by extension, to refer to the clock, the tower and the bell collectively, although the nickname is not universally accepted as referring to the clock and tower. Some authors of works about the tower, clock and bell sidestep the issue by using the words Big Ben first in the title, then going on to clarify that the subject of the book is the clock and tower as well as the bell.

Cultural importance


The clock has become a cultural symbol of the United Kingdom, particularly in the visual media. When a television or film-maker wishes to indicate a generic location in the country, a popular way to do so is to show an image of the tower, often with a red double-decker bus or black cab in the foreground.

In 2008 a survey of 2,000 people found that the tower was the most popular landmark in the United Kingdom. It has also been named as the most iconic film location in London.

The sound of the clock chiming has also been used this way in audio media, but as the Westminster Quarters are heard from other clocks and other devices, the sound is by no means unique. Big Ben is a focus of New Year celebrations in the United Kingdom, with radio and TV stations tuning to its chimes to welcome the start of the New Year. To welcome in 2012, the clock tower was lit with fireworks that exploded at every toll of Big Ben. 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 the two minutes' silence. Londoners who live an appropriate distance from the tower and Big Ben can, by means of listening to the chimes both live and on analogue radio, hear the bell strike thirteen times. This is possible because the electronically transmitted chimes arrive virtually instantaneously, while the "live" sound is delayed travelling through the air since the speed of sound is relatively slow.

ITN's News at Ten opening sequence formerly featured an image of the tower with the sound of Big Ben's chimes punctuating the announcement of the news headlines. The Big Ben chimes (known within ITN as "The Bongs") continue to be used during the headlines and all ITV News bulletins use a graphic based on the Westminster clock dial. Big Ben can also be heard striking the hour before some news bulletins on BBC Radio 4 (6 p.m. and midnight, plus 10 p.m. on Sundays) and the BBC World Service, a practice that began on 31 December 1923. The sound of the chimes is sent live from a microphone permanently installed in the tower and connected by line to Broadcasting House.

At the close of the polls for the 2010 general election the results of the national exit poll were projected onto the south side of the tower. On 27 July 2012, starting at 8:12 a.m, Big Ben chimed 30 times, to welcome in the London Olympic Games (i.e. the 30th Olympiad), which officially began that day.

Cultural Depictions
The Clock Tower features in many dramatic representations, and as a specific location in:
 * My Learned Friend, 1943 film starring Will Hay
 * Peter Pan, 1953 Walt Disney animated feature
 * "The Nightmare Man", a 1978 episode of Return of the Saint starring Ian Ogilvy
 * The Thirty-Nine Steps, 1978 film starring Robert Powell
 * "The Great Mouse Detective", a 1986 Walt Disney animated feature
 * "Shanghai Knights", a 2003 film starring Jackie Chan
 * "Aliens of London", a 2005 Doctor Who episode

2017 Renovation
The Elizabeth Tower and Great Bell have been scheduled for a major renovation which is expected to last three years and is due to begin in early 2017. Essential maintenance will be carried out on the clock mechanism, which will be stopped for several months during which there will be no chimes. Striking and tolling will however be maintained for important events.

The aim of the renovation is to repair and conserve the tower, upgrade facilities as necessary, and to ensure its integrity for future generations. The last significant renovation work was carried out to the tower over 30 years ago in 1983-85. The most significant addition to the tower in the forthcoming works will be the addition of a lift.