The top of the clock tower, housing the Ayrton Light, which is lit whenever Parliament meets after dark. The lantern is named after Thomas Ayrton, the first Commissioner of Works, who had the lamp installed.
Big Ben is probably the most photographed building in London. Almost all the tourists who come to the capital have the great clock tower of the Palace of Westminster firmly on their itinerary. This is partly because it is unique – there is really no other building in the world quite like it – but also because its huge clock and sonorous bells seem to embody the best of British engineering and accomplishment. Yet the story of the building suggests something different, and the familiar exterior conceals a complex and intriguing interior.
The top of the clock tower, housing the Ayrton Light, which is lit whenever Parliament meets after dark. The lantern is named after Thomas Ayrton, the first Commissioner of Works, who had the lamp installed.
Big Ben is, strictly, not a building at all. The name refers not to the tower, but to the giant bell on which the clock strikes each hour, though the name long ago passed into common usage as a description of the whole structure – tower, clock and bells. It is thought to have acquired its sobriquet in reference to either Sir Benjamin Hall, the Chief Commissioner of Works in the 1850s, or Ben Caunt, a giant boxer of the period.
The entrance to the clock tower.
The 334 steps to the belfry.
The tower of Big Ben stands 316 ft (96 m) high, and the staircase that winds up to the belfry has 334 steps, with a further fifty-nine to the lantern at the summit. The building, now officially known as the Elizabeth Tower, was begun in 1843, to designs by Sir Charles Barry, following a disastrous fire nine years earlier. Unusually for the period, the central core of the tower was erected first and the exterior added as the structure rose, but progress was slow and, when completed in 1859, the project was five years behind schedule. The centrepiece of the tower was to be a clock of unprecedented size and accuracy, and a competition was held for its design in 1846. The requirement was that the first strike of each hour should be accurate to within one second, and after five fruitless years a design was accepted from Edmund Beckett Denison, an MP with a strong amateur interest in horology, who was to become Lord Grimthorpe. The clock was constructed by E.J. Dent, a London firm more accustomed to manufacturing high-class pocket watches and chronometers for the Royal Navy. Grimthorpe’s enormous clock has a pendulum 14 ft 5 in (4.4 m) in length and a mechanism 15½ ft (4.7 m) long, weighing around 5 tonnes. The clock was completed in 1854, but stood in Dent’s workshops pending completion of the tower and was not installed until 1859.
Inside the south clock face.
The clock controls five bells, four to strike the quarter hours and mighty Big Ben itself. The current bell is the second, a replacement for the original which, to continue the theme of this troubled enterprise, cracked during testing in 1858. The 16-ton monster was broken up and recast to a lighter, but slightly larger, specification. The new bell survived initial testing but proved too wide to be hauled directly up the tower. It was turned through 90 degrees and, over thirty torturous hours, winched into the belfry. Next, the hands on the four enormous dials proved too heavy and stopped the clock. The solution lay in hollow minute hands – which are 14 ft (4.2 m) long – made from copper. The clock was started in July 1859, but the drama continued two months later when Big Ben developed a crack, and was silent for four years. The crack was said to have been caused by the deployment of a hammer that was too heavy for the bell. It was repaired, but the crack is visible to this day, and audible in the bell’s sonorous, slightly imperfect tone. The mechanism has belied its troubled gestation by performing with remarkable accuracy. It has undergone few modifications since 1859 and is still regulated by the use of old pre-decimal coinage, which is placed on the pendulum rod. The addition of a single old copper penny causes the clock to gain two-fifths of a second in twenty-four hours.
