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 member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

A surfer heads out at Coldingham Bay an inlet in the North Sea on February 15, 2012 in Coldingham, Scotland. (Photo by Jeff J. Mitchell/Getty Images)

A young sloth named Gloria, that was rescued after being stolen from the wild destined for trafficking, peeks out of the box it is being taken to be released at the city's Botanical Garden in Rio de Janeiro, Brazil, Monday, March 13, 2023. Gloria was cared for by the Free Life Institute NGO that rehabilitates injured wildlife found in the surrounding Rio area and returns them, when possible, back to the wild. Those that are too injured to be released are sent to other rehab centers or sanctuaries to live out their lives in protected environments. (Photo by Bruna Prado/AP Photo)

A cloud of black smoke billows out the exhaust pipe of John Robertson's diesel dragster as he runs down the track during the 2015 NHRA Kansas Nationals, Friday, May 22, 2015, at Heartland Park in Topeka, Kan. (Photo by Chris Neal/The Topeka Capital-Journal via AP Photo)