Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

A couple passes the sculpture “Transformer” by Chinese artist Bi Heng during snowfall in Kassel, central Germany, Tuesday March 12, 2013. Frankfurt airport closed, a quarter of flights out of Paris were canceled, Belgium suffered record traffic jams and high-speed trains were stuck in stations – all because of a sudden dump of oddly late snowfall on Western Europe. Less prepared for the kind of heavy snow that regularly hits northern and eastern neighbors, France, Britain and Belgium struggled Tuesday to keep moving amid the frosty, blustery conditions. (Photo by Uwe Zucchi/AP Photo/Dpa)

A veterinarian kisses an 8-month-old cat, wearing a prosthetic two-wheel device, at a veterinary hospital in Chongqing municipality, March 16, 2015. The cat's rear legs lost the abilty to walk after falling from the ninth to fifth floor of a building last November, its since undergone four major surgeries which included removing parts of its organs, local media reported. (Photo by Reuters/China Daily)

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

Soldiers, including two recruits who have brought some chickens, at Victoria prepare to board the train for the battle front. (Photo by Hulton Archive/Getty Images)

“Unexpected x2 (a.k.a. “how much is that doggie in the window”)”. Taiwan, 2011. (Photo and caption by Asian (Street) Impressions)

A Chicago Police Officer runs toward gunfire as looters break into downtown stores in the early hours of the morning on August 10, 2020. (Photo by RMV/Rex Features/Shutterstock)

UEFA staff member carry away the trophy from the pitch prior the UEFA Champions League semi-final football match between Leipzig and Paris Saint-Germain at the Luz stadium in Lisbon on August 18, 2020. (Photo by David Ramos/Pool via AFP Photo)