A man walks down a flooded road in Islip, New York August 13, 2014. More than a foot of rain hit parts of New York's Long Island on Wednesday, enough to set a preliminary state record, triggering flash floods and swamping cars on major roads that were turned into rivers during the morning rush hour. (Photo by Lucas Jackson/Reuters)

A recruitment drive during the First World War at Trafalgar Square, London. (Photo by Central Press/Getty Images)

Indonesian air force personnel carry the flight data recorder of the ill-fated AirAsia Flight 8501 that crashed in the Java Sea, at airport in Pangkalan Bun, Indonesia, Monday, January 12, 2015. Divers retrieved one black box Monday and located the other from the AirAsia plane that crashed more than two weeks ago, a key development that should help investigators unravel what caused the aircraft to plummet into the Java Sea. (Photo by Achmad Ibrahim/AP Photo)

A British woman plays a piano designed especially for people who are confined to bed. Date: 1935. (Photo by Mary Evans Picture Library/Caters News)

Dancers audition for a post as cheerleaders of the Miami Dolphins, in Rio de Janeiro, Brazil, Thursday, March 3, 2016. Brazilian dancers audition in the first international cheerleader recruitment for the Miami Dolphins in Rio de Janeiro. The Dolphins will also hold auditions in Colombia, Argentina, Mexico and South of Florida. (Photo by Felipe Dana/AP Photo)

Afghan protesters beat a policeman after a suicide attack that targeted crowds of minority Shiite Hazaras during a demonstration at the Deh Mazang Circle of Kabul on July 23, 2016. Islamic State jihadists claimed responsibility for twin explosions July 23 that ripped through crowds of Shiite Hazaras in Kabul, killing at least 61 people and wounding 207 others in apparently their deadliest attack in the Afghan capital. The bombings during a huge protest over a power transmission line could deepen sectarian divisions in a country well known for communal harmony despite decades of war. (Photo by Wakil Kohsar/AFP Photo)

Tube passengers take a selfie next to a London underground roundel designed for the launching of the Night Tubes on display at Oxford Circus underground station in London, Britain, 19 August 2016. The long delayed Night Tubes service launched on 19 August. The 24-hour service will operate on Fridays and Saturdays. (Photo by Hannah Mckay/EPA)

Passengers wait at the departure hall of the Beijing Railway Station in central Beijing, China January 27, 2017 as China gears up for Lunar New Year, when hundreds of millions of people head home. (Photo by Damir Sagolj/Reuters)