Water polo was invented in the middle of the nineteenth century, apparently to amuse swimmers in training.The name water polo derives from the fact that in the earliest form of the game the players were mounted astride barrels and used their paddles to propel the ball. In time the game changed to a sort of water baseball, and then to water football and finally the water handball that it has become today. The rules of the present game were codified in the early twentieth century.Two teams of seven players each compete in four seven-minute periods in which each team tries to score more goals than their opponents. In the event of equal scores at the end of the set time, extra time is given to decide the issue.In Barcelona in 1992 six periods of extra time were needed to produce a winning team.Hungary, with six titles won in twelve finals played is the top Olympic water polo nation. Hungary's most memorable victory was over the USSR in 1956. The match ended in an all in fight in the pool while in Budapest Soviet tanks were attempting to put down a rebellion by the Hungarian people.At the Saint Louis games in 1904 there were not enough teams for a tournament, so the United States entered three teams and cleaned up all the medals. The pool in which the tournament was played was also used as a cattle trough, and a few months after the games three of the finalists died of typhoid fever.