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)

A little girl hangs three Siamese kittens on a washing line in a garden in Croydon, London. (Photo by Fox Photos/Getty Images). 14th July 1931

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)

A child attends a training session in a swimming pool on July 10, 2007 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

A woman participates in the “Carnaval na Central” block party in Rio. (Photo by Felipe Dana/Associated Press)

“Monorail Subway, Capitol To Senate. The Car. Senators Swanson And Townsend As Passengers, 1916”. (Photo by Harris & Ewing Collection). (Please click to enlarge)

Fireworks explode over Elizabeth Tower housing the Big Ben clock in London. (Photo by Kirsty Wigglesworth/Associated Press)