A silicon rug in the form of Adolph Hitler on display during an exhibition by Israeli artist Boaz Arad, at the Center for Contemporary Art February 22, 2007 in Tel Aviv, Israel. Arad is an Israeli artist who is dealing with the Holocaust in a provocative way. He uses the Holocaust to discuss human evil and contemporary Israel, which he says is torn and crumbling. (Photo by David Silverman/Getty Images)

A nurse consoles herself with a box of chocolates as she reads a paper-back thriller. (Photo by Hulton Archive/Getty Images). Circa 1955

Two dummy tanks being pushed along a road by German soldiers. (Photo by Hulton Archive/Getty Images). Circa 1925

11th February 1974: A Maori wields his spear to terrifying effect, during the state visit of Queen Elizabeth II and Prince Philip to New Zealand.

King George V inspects the day's kill after a tiger hunt in India during his royal visit to celebrate his accession to the throne. (Photo by Hulton Archive/Getty Images). 1911

Grafitti by the illusive artist Banksy adorns the levee wall in the Lower Ninth Ward on August 29, 2008 in New Orleans, Louisiana. New works by the artist, whose paintings are also sold in galleries, have been popping up throughout New Orleans coinciding with the third anniversary of Hurricane Katrina. (Photo by Chris Graythen/Getty Images)

A caterpillar driven ferry with a 24 horsepower engine takes holidaymakers from the mainland at Bigbury in Devon to Burgh Island, a quarter of a mile away. (Photo by Reg Speller/Fox Photos/Getty Images). 4th April 1935

The first load of passengers queuing for the Bennie Railplane in Glasgow; the inventor George Bennie is third in the queue. The streamlined cars are self propelled, driven by air screws in front and behind, and hang from a steel girder. (Photo by J. A. Hampton/Topical Press Agency/Getty Images). 4th July 1930