A dog welcomes a volunteer at the “Ping An A Fu” (“Safe and Happy”) Homeless Animals Rescue Center on September 11, 2006 in Nanjing of Jiangsu Province, China. (Photo by China Photos/Getty Images)

An x-ray of a woman drinking, taken by British artist and photographer Hugh Turvey in London, England. (Photo by Hugh Turvey/SPL/Barcroft Media)

Brick-carving featuring Tang Dynasty (AD 618-907) maids performing musical instruments is seen at the Chinese Music History Museum in Xian University of Architecture and Technology on September 27, 2008 in Xian of Shaanxi Province, China. (Photo by China Photos/Getty Images)

The Dynasphere, an electrically-driven wheel, invented by Mr. J. A. Purves of Taunton and his son. It had 2.5 horse power and once attained a speed of 25 mph. (Photo by Fox Photos/Getty Images). 1932

Hot air balloons fly during the Irish hot air ballooning championships in Galway, Ireland September 26, 2016. (Photo by Clodagh Kilcoyne/Reuters)

Hillary Clinton waves to a selfie-taking crowd at a recent campaign event in Orlando, Florida on September 26, 2016. (Photo by Barbara Kinney/Hillary for America)

An installation with a copy of a tank is seen at a villager's house in the village of Vits, Belarus November 8, 2016. (Photo by Vasily Fedosenko/Reuters)

A truck driver cleans the mirror of his decorated truck in Charsadda outside Peshawar, Pakistan October 18, 2016. (Photo by Fayaz Aziz/Reuters)