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

Afghan women learn how to make a doll at a workshop sponsored by a Malaysian NGO called Mercy that seeks to help local females to empower themselves on April 15, 2010 in Kandahar, Afghanistan. (Photo Majid Saeedi/Getty Images)

A horse-drawn cart passing through a section cut out of the base of a giant sequoia tree in the Mariposa groves of Yosemite Park, California. (Photo by Carleton E Watkins/Getty Images). 1870

Two horses fight during a Xinhe Festival in Peixiu Village of Antai Township in Rongshui Miao Autonomous County on July 11, 2016 in Liuzhou, Guangxi Zhuang Autonomous Region of China. Xinhe Festival is one of the most popular traditional festivals in Rongshui with various entertainment activities. (Photo by VCG/VCG via Getty Images)

Spunky runs during the third heat of a dog race Monday, September 1, 2014, at Canterbury Park, in Shakopee, Minn. Canterbury Park hosted their annual Labor Day Wiener Dog Wars in which dogs competed in seven races on the horse track for the title of Grand Champion. (Photo by Jeff Wheeler/AP Photo/The Star Tribune)