Tennis, a game of ball, played in a court built for the purpose, with a playing floor 112 by 40 ft., end walls 30 ft. high, side walls 20 ft. high, and usually lighted by skylights or windows above the 20-foot line. The players are two or four persons divided as partners on the "service" side and the "hazard" side. The ball is struck with a bat, called a racket, the striking part of which is covered with a close hard network of tendon. The player or party in strikes a ball, or " serves " it, against the head wall of the court. This ball must come to the ground over "the line," which is a network stretched across the middle of the court, 5 ft. high at each end and 3 ft. high in the middle. It is returned by the player or party out, who must in turn deliver it, by its rebound, at a certain place in the court, when it is again struck by the player in; and so the game continues. Whoever fails to " put the ball up" properly on the head wall, or to deliver it at the proper place on the court, loses. If it is the player in that fails, he loses his hand and goes out; if it is the player already out, his adversary scores a stroke toward game.

There are several other contingencies which go to making the score, and the numerous angles caused by the walls constitute the intricacies of the game. - The name is from the French tenez, hold, as in striking the ball the racket must be held firmly. The game originated in France in the 15th century, and Louis XL, Henry II., and Charles IX. were expert players. M. Barre, who died in 1873, for many years superintendent of the tennis court in the Tuileries, was considered the best player that ever lived. The oldest English tennis court was built early in the 16th century in Hampton Court palace. There are two or three club courts in London, one at Leamington, and one at Brighton.