Alan Wilson, Director of James Ritchie & Son clockmakers, founded in 1809, adjusts a clock face at the Cannongate Tobooth to British Summer Time on March 21, 2012 in Edinburgh, Scotland. The Tolbooth, built in 1591, was where tolls and public dues were collected. The clock face dates back to 1820 and replaced an earlier clock from the 17th Century. Clocks will be put forward by one hour on Sunday March 25, 2012 at 1.00am and British Summer Time (BST) will officially start. (Photo by Jeff J. Mitchell/Getty Images)

A preparatory model of the Imperial State Crown of India worn in 1911 by King George V stands next to original ledgers dating from 1735 in Garrard's flagship store in Mayfair on April 6, 2011 in London, England. Garrard is the world's oldest jewellers having been founded by George Wickes in 1735 and soon after appointed as goldsmith to the Prince of Wales. For over 160 years Garrard held the title of Crown Jeweller, bestowed by Queen Victoria in 1843, Garrard have served six successive monarchs. They have produced several royal crowns as well as the engagement ring presented to Kate Middleton by Prince William and formerly Princess Diana's engagement ring. (Photo by Oli Scarff/Getty Images)

Laura Titch, dressed as Mary of Guise, and Duncan Maclachlan, dressed as Alexander of Stewart, rehearse for Stirling Castle's grand renaissance palace opening on June 3, 2011 in Stirling, Scotland. The palace has been closed for two years, while a Ј12 million pound project was undertaken to return the palace to how it might have looked back in the 1540s, when it was home to Mary of Guise, the widow of James V. Their daughter, Mary Queen of Scots, was raised there before living in France. (Photo by Jeff J Mitchell/Getty Images)

An Israeli jail authority officer escorts a prison van containing Palestinian prisoners as it enters Hasharon jail on October 16, 2011 in Tel Mond, Israel. IDF soldier Gilad Shalit is to be freed from 5 years of captivity in Gaza in an exchange deal which will see the release of 477 Palestinian prisoners in an initial deal with another 550 to freed after the return of Shalit. (Photo by Uriel Sinai/Getty Images)

Artists preform on a pool suspended above the audience during the Fuerza Bruta dress rehearsal on February 1, 2012 in Tel Aviv, Israel. (Photo by Uriel Sinai/Getty Images)

The Soyuz TMA-18M spacecraft is transported from an assembling hangar to its launch pad at the Baikonur cosmodrome, Kazakhstan, August 31, 2015. The Soyuz is scheduled to blast off with Aidyn Aimbetov of Kazakhstan, Sergei Volkov of Russia and Andreas Mogensen of Denmark to the International Space Station (ISS) on September 2, 2015. (Photo by Shamil Zhumatov/Reuters)

Marcos Trujillo cleans the engines of a boat made by Contender in preparation for tomorrow's opening day of the four day long Progressive Insurance Miami International Boat Show at the Miami Beach Convention Center on February 15, 2012 in Miami Beach, Florida. The boat show features more than 3,000 boats and 2,000 exhibitors from all over the globe. (Photo by Joe Raedle/Getty Images)

Melissa Sinclair livestock apprentice prepares seven year old Maisie the Highland cow ahead of the International Highland Cattle Show being held at Pollock Country Park on September 15, 2011 in Glasgow, Scotland. This year's event , takes place on Saturday 17th in the grounds of the park, with 30 breeders from across the UK attending with more than 100 head of cattle competing in 12 classes, to win the supreme champion. (Photo by Jeff J Mitchell/Getty Images)