A team of researchers from the University of Leicester has used a technique called ‘laser Doppler vibrometry’ to measure four of Big Ben’s chimes (9am to 12 noon).

They created a 3-D computer model of the Westminster bell and then used lasers to map the vibrations as it chimed. The project was featured in a BBC4 programme called Sound Waves: The Symphony of Physics.

Martin Cockrill, a technical specialist at the university, said: “Many of the vibrations in the metal of Big Ben are too tiny to be seen by the naked eye. Using the lasers; we were able to get over 500 measurements across the surface, which just wouldn’t have been possible with previous technologies.”

Cast at the Whitechapel Bell Foundry in London in 1858, Big Ben weighs 13.7 tonnes and is one of the largest bells in the UK. An earlier bell, cast in 1856, was damaged beyond repair due to the striking hammer being too heavy.

Big Ben is to fall silent later this year — for the first time since 2007 — for a renovation project. The mechanism of the clock is said to be in a “chronic state”, and there are concerns that the fabric of the tower is reaching an “acute condition”.