Crew members work to secure a hot-air balloon after landing at the city of Luxor, south of Cairo, Egypt December 13, 2016. (Photo by Amr Abdallah Dalsh/Reuters)

Passengers watch as The Waverley, the world's last remaining seagoing passenger paddle steamer arrives at Clevedon Pier on June 10, 2011 in Clevedon, England. Built in 1946, the trust which owns and operates the Waverley, is warning that this could be the last season for the vessel and is appealling for more public funding saying it is struggling to make ends meet in the current financial climate due in part to rising fuel costs. Restored in 1973 after service on Loch Long in Scotland, since 2003, Waverley has been listed in the British National Register of Historic Ships core collection as 'a vessel of pre-eminent national importance'. (Photo by Matt Cardy/Getty Images)

A girl poses at an entrance of her house next to a bomb dropped by the U.S. Air Force planes during the Vietnam War, in the village of Ban Napia in Xieng Khouang province, Laos September 3, 2016. From 1964 to 1973, U.S. warplanes dropped more than 270 million cluster munitions on Laos, one-third of which did not explode, according to the Lao National Regulatory Authority. (Photo by Jorge Silva/Reuters)

“Liu Bolin is an artist born in China’s Shandong province in 1973, and he earned his Bachelor of Fine Arts from the Shandong College of Arts in 1995 and his Master of Fine Arts from the Central Academy of Fine Arts in Beijing in 2001. His work has been exhibited in museums around the world. Also known as “The Invisible Man”, Liu Bolin's most popular works are from his “Hiding in the City” series; photographic works that began as performance art in 2005”. – Wikipedia. (Photo by Reuters/China Daily)

From the 1940s through the 1960s, the Alfred Mainzer Company of Long Island City, NY published a series of linen and photochrome humorous cat postcards illustrated by Eugen Hartung (or Hurtong) (1897–1973), sometimes referred to as “Mainzer Cats”. These postcards normally illustrate settings that are filled with action, often with a minor disaster just about to occur. While the dressed cats were by far the most popular and most plentiful cards, Hartung also painted other dressed animals – primarily mice, dogs, and hedgehogs.

A dancer warms up backstage before the final of the 46th Prix de Lausanne, in Lausanne, Switzerland, 03 February 2018. Launched in 1973, the Prix de Lausanne is an international dance competition for young dancers aged 15 to 18. Closing the six-day event, prizes are awarded to the best of 21 finalists consisting of scholarships granting free tuition in a world-renowned dance school or dance company. (Photo by Valentin Flauraud/EPA/EFE)

Abbas (1944 – 25 April 2018) was an Iranian photographer known for his photojournalism in Biafra, Vietnam and South Africa in the 1970s, and for his extensive essays on religions in later years. He was a member of Sipa from 1971 to 1973, a member of Gamma from 1974 to 1980, and joined Magnum Photos in 1981. Here: Kuwait, 1991. (Photo by Abbas Attar/Magnum Photos)

Participants arrive at the finish line during the annual Maldon Mud Race in Maldon, east England on May 7, 2017. Originating in 1973, the race involves competitors racing around a course through the River Blackwater in Essex at low tide. (Photo by Daniel Leal-Olivas/AFP Photo)