An injured fan is helped by a riot policeman during clashes between Red Star Belgrade and Partizan Belgrade fans in the stadium before the teams' Serbian Superliga soccer match in Belgrade, April 25, 2015. Serbian league leaders Partizan Belgrade held champions and bitter city foes Red Star to a 0-0 draw in a derby match marred by bad crowd trouble before kickoff on Saturday. The start was delayed for 45 minutes after home Red Star supporters pelted riot police with seats and flares, forcing officers to retreat from the north tier that houses the club's diehard fans. (Photo by Marko Djurica/Reuters)

Employees conduct a final check to fix any cavities in the seams of balls inside the soccer ball factory that produces official match balls for the 2014 World Cup in Brazil, in Sialkot, Punjab province May 16, 2014. It was when he felt the roar of the crowd at the 2006 World Cup in Germany that Pakistani factory owner Khawaja Akhtar first dreamt up a goal of his own: to manufacture the ball for the biggest soccer tournament on the planet. Last year he finally got his chance – but only 33 days to make it happen. (Photo by Sara Farid/Reuters)

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)

A new monorail service in Houston, Texas, ready for its inaugural service. (Photo by Evans/Three Lions/Getty Images). Circa 1950

Actress Athene Seyler attempts to contort her body, in a scene from the show, “Skin Deep”. (Photo by Sasha/Getty Images). Circa 1928

Old Heidelberg, Dog with Pipe, 1905. (Photo by Detroit Publishing Company)

British sailors taking shore leave on the British dependency of Gibraltar visit the Suiza Bar to watch a Spanish dancer perform on August 05, 1954. These Spanish entertainers are under contract and must return over the border by 11 o'clock. (Photo by Bert Hardy/Getty Images)