A child stands inside a large soap bubble made by a street artist at the Mayor square in central Madrid, Friday, December 9, 2016. (Photo by Francisco Seco/AP Photo)

A boat sails behind a woman looking through binoculars as she sits on a cliff on a sunny day in Sydney, Australia, May 29, 2016. (Photo by David Gray/Reuters)

Dr. P.A. Smithe was sent by the American Red Cross as a doctor and surgeon to work at a hospital in Vienna. He sailed to Europe in December 1915 and returned home in August 1916, according to his daughter, who donated his images to the National World War I Museum. Photo: Turkish army, including cavalry, infantry and artillery. (Photo by Dr. P.A. Smithe/National World War I Museum, Kansas City, Mo.)

A woman sits as she gets a tattoo on her leg during the annual Panama City Ink Fest in Panama City August 16, 2015. (Photo by Carlos Jasso/Reuters)

U.S. Marines kick in a door while securing a building next to the main hospital in central Baghdad April 15, 2003, which will be used as a temporary Iraqi police headquarters. (Photo by Jerry Lampen/Reuters)

Filipino boys play basketball at an improvised court hooked on multi-layered tombs at a public cemetery in Navotas, north of Manila, Philippines on Thursday Oct. 31, 2013. Filipinos are expected to flock to cemeteries on November 1 to remember their dead as they observe All Saints Day in this predominantly Roman Catholic country. (Photo by Aaron Favila/AP Photo)

Officers react at their graduation ceremony during Iraqi Army Day anniversary celebration in Baghdad January 6, 2015. Iraqi Defence Minister Khaled al-Obeidi said on Tuesday that the Iraqi military has started rebuilding after its near total collapse last summer but that the effort is still in its initial phase. (Photo by Ahmad Mousa/Reuters)

German flying ace Baron Manfred von Richthofen (1892–1918) also known as The Red Baron with his dog Moritz, circa 1916.