A model of a prehistoric icthyosaurus is dragged from its pond in the grounds of Crystal Palace, London, for its annual clean. The 'keeper' is being helped by some of the local police force. (Photo by Fox Photos/Getty Images). February 1927

A rare turquoise mosaic mask is displayed at The Britrish Museum on April 7, 2009 in London, England. The Aztec mask, originally from Mexico will be one of the key exhibits to go on show at the Moctezuma: Aztec Ruler exhibition which opens to the public on 24 September 2009. (Photo by Dan Kitwood/Getty Images)

A sculpture of a swimming man is displayed on the banks of the Thames on September 18, 2007 in London. The new artwork, unveiled today, is to promote a new television programme set in a tattoo parlour. (Photo by Peter Macdiarmid/Getty Images)

Bunting hangs on Regent Street on April 19, 2011 in London, England. Preparations are underway across the city as the Royal wedding of HRH Prince William and Kate Middleton draws nearer. (Photo by Dan Kitwood/Getty Images)

Lance Sergent Martin Mitchell (R) pins medals to Coldstream Guardsman Martin Hughes in the Tailor Shop in Wellington Barracks on April 20, 2011 in London, England. Soldiers involved in the Royal Wedding of Prince William and Catherine Middleton are preparing their ceremonial duties ahead of the day. (Photo by Oli Scarff/Getty Images)

Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

Daisy Lowe attends The Phillips British Academy Awards 2011 at The Grosvenor House Hotel on May 22, 2011 in London, England. (Photo by Dave Hogan/Getty Images)

Kaci Nuyen 8, holds a “Kiddizoom Twist” camera during a Hamleys Christmas toy photocall at Hamleys Toy store on June 28, 2011 in London, England. The famous toy store unveiled today their “must have” toys for Christmas 2011. (Photo by Dan Kitwood/Getty Images)