Big Ben celebrates its 150th birthday today.

Contrary to popular belief, Big Ben is not the clock tower but merely the great bell of the clock (but that's being pedantic).

The clock tower is St Stephen's Tower. But, if you consider Big Ben to also be the clock (as many people do) then today is Big Ben's 150th birthday - the clock started ticking on 31st May 1859.

It is the world's largest four-faced, chiming clock and the third largest free-standing clock tower in the world.

Cast in 1856, the first bell was transported to the tower on a trolley drawn by sixteen horses, with crowds cheering its progress. Unfortunately, it cracked beyond repair while being tested and a replacement had to be made. The bell was recast at the Whitechapel Bell Foundry in east London as a 13.76-tonne (13˝ ton) bell.

This was pulled 200ft up to the Clock Tower’s belfry, a feat that took 18 hours. It first chimed in July 1859. Just two months later, the hammer that struck it caused the bell to crack.

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 reinstalled. 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 an odd twang ever since and is still in use today complete with the crack. That odd twang gives Big Ben its unique sound, famous around the world - the sound of Britain.

Big Ben was also severely damaged by the Luftwaffe in 1941 but has since been repaired to its former glory.

Where did Big Ben get its name from? That's something of a mystery.

The bell was never officially named, but the legend on it records that the commissioner of works, Sir Benjamin Hall, was responsible for the order. 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 Telegraph
31st May 2009

Big Ben turns 150 today

The clock started keeping time on May 31 1859...

...the bells began ringing on July 11. To be pedantic, Big Ben is really only the great bell and not the clock tower itself

The chimes are based on a snatch on Handel's Messiah

The tower is 314 feet high, roughly 16 storeys

Tunnelling for the Jubilee line left the tower leaning 8.66 in to the North-West

The minute hand is 14-ft long, the hour hand is 9-ft long

The north and east faces of the clock have heaters to prevent the hands freezing

The clock face is cleaned by abseilers every five years

It is the biggest CHIMING clock tower in the world...

....But in terms of size it is easily beaten. The clockface on the top of the Royal Liver Building in Liverpool is bigger. Worldwide, it looks like a wrist-watch compared to the clock on the Abraj Al Bait Towers in Mecca whose face, when finished, will measure 80 metres to Big Ben’s puny 6.9 metres

Each face is lit by 27 bulbs - low-energy and radio-controlled nowadays

The bell was made in Whitechapel. The bell's tone is E flat – very flat, in fact, due to cracks in the bell

The bell's famous crack which gives Big Ben its unique sound

The flatbed clock mechanism – revolutionary 150 years ago – ticks with remarkable accuracy

The 15 ft pendulum that controls the time-keeping keeps on swinging at two-second intervals, with minor adjustments for expansion or contraction using pre-decimal pennies: a 1d coin speeds the clock up by 2/5th of a second over 24 hours

A photo taken last year of the Whitechapel Bell Foundry Yard, Britain’s oldest manufacturing firm, in east London. It's the birthplace of Big Ben

Last edited by Blackleaf; May 31st, 2009 at 12:31 PM..