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

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

A visitor walks past an installation artwork entitled “Confuciuse” which combines the word “Confucius” and “confuse” in the contemporary art exhibition at “Fun and Art” Festival on December 13, 2008 in Xian of Shaanxi Province, China. (Photo by China Photos/Getty Images)

Workers feed water to a Slow Loris at the Guangdong Wild Animal Rescue Centre on December 21, 2004 in Guangzhou, China. Many protected species at the Centre have been seized by Police from illegal traders. (Photo by China Photos/Getty Images)

In this photo illustration a plastic carrier bag is blown along the road by the wind on March 4, 2008 in Birmingham, England. (Photo illustration by Christopher Furlong/Getty Images)

Hao Han (8), Shaolin kung fu student and child actor. Shaolin Monastery, Henan. (Photo by Mathias Braschler and Monika Fischer)

Synalpheus iocasta; Singapore Marine. (Photo by Arthur Anker)

A demonstrator is detained during May Day rallies in Santiago May 1, 2013. (Photo by Ivan Alvarado/Reuters)