The game of polo, which is believed by the best European authorities to have originated in Persia, was introduced into Japan from China in the sixth or seventh century after Christ. It is known here by the Chinese name of, da-kyū literally, "striking balls." A Japanese poet of the early part of the eighth century mentions pọlo as being then a favourite pastime at Court. It still remains essentially aristocratic, as a game played on horseback and entailing considerable apparatus and expense can scarcely fail to do.

The Japanese polo club, or rather racket, weighs a trifle under 2 ounces. It has a tapering bamboo handle some 3 ft. 6 in. in length, and of about ½ in. diameter at the thick end. To the thin end is spliced, with silk or cotton cord, a flat piece of split bamboo ½ in. in width, bent round so as almost to form a frame, and kept in position by a piece of double cord fastened from its extremity to the handle just above the splicing. Across this frame a light net of silk or cotton cord is stretched sufficiently loosely to avoid elasticity, but not loosely enough to present any "catch" in slinging the ball. The interior of this scoop or net measures 4 in. by 2 1/2 in. The balls are of four kinds,- plain white, plain red, banded red, and banded white. They measure 1 1/2 in. in diameter, weigh about 1 1/4 ounce, and are formed of small pebbles wrapped in rice straw or bamboo fibre, and coated with several layers of thin paper fastened up with rice paste.

The correct number of' players is fourteen-seven a side-but the game is sometimes played with a greater and often with a less number. Each side wears a distinctive badge-white and some colour. The players with white badges play with white balls, those with coloured badges play with red balls.

The court is a rectangular enclosure railed in by a stout bamboo post and rail fence about 4 ft. high, except at one end, where a boarded fence or screen about 8 ft. high replaces the post and rail. In the centre of this screen is a circular hole about 1 ft. 6 in. in diameter, behind which is fixed a netted bag rather longer than an ordinary landing-net. This is the goal. Eighteen ft. from this goal screen, another post and rail about 3 ft. 6 in. high are fixed as a barrier right across the enclosure. Three ft. nearer the goal, a balk-line formed by a bamboo embedded in the earth is fixed paralled to the barrier and goal fence. At the other end (entrance end), another barrier forms a small enclosure for attendants with balls and rackets. Close to this end are openings in the side post and rails, allowing the players ingress and egress. The space thus railed in measures 180 ft. from barrier to barrier, 60 ft. from side to side.

The players having entered the enclosure on horseback, each provides himself with a ball of similar colour to the badge worn by his side, the ball being carried balanced in the net of the racket. Each side then forms in single file at the entrance end of the enclosure, so that the two files are parallel both to the borders of the enclosure and to one another. The border of the enclosure which each side occupies is denoted by a flag and string of balls of the colour proper to that side, placed right and left of the goal. Each horseman faces goal, but also slightly turns his horse inwards, so as to face somewhat towards his corresponding opponent also. Each player then raises his racket, with the ball balanced on the net, to a horizontal position across his chest, breast high-the club being held in the right hand- and thus awaits the word to start. This being given, both sides canter en masse to the "goal barrier," and endeavour to sling their balls through the "goal hole," at the same time obstructing foes and protecting friends as far as possible. The object of the players, on both sides, during this first stage of the game, is to score seven balls of their respective colours as soon as possible. Should a player inadvertently put a ball of the opponents' colour into goal, it scores for them, and against his own side. The duration of each game being limited to half-an-hour, scoring is of more importance during the first stage than obstructing. Consequently the play is chiefly confined to shooting at goal. If, however, one side gains a long lead at starting, it is usual for the other side to station a "goal keeper," in front of the goal to impede the shooting of the successful side. At the entrance end of the court, behind the barrier, are piles of balls of both colours. It is usual for a player of each side to supply his allies with ammunition, by slinging up balls of their colour towards the goal. For during the first stage of the game the number of balls in play is practically unlimited, those only being out of play which fall outside the enclosure, or remain between the balk-line and goal screen. It is not "good form" to sling the opponents' balls out of the enclosure, but it is so to return them towards the entrance end.

The fragile nature of the rackets necessitates gentle play, and reduces hitting or striking to a minimum. It is not allowable to handle the ball, or to carry it in any other way than in the racket net. The score is kept by means of two strings of seven balls each, of the respective colours of the two sides. These strings of balls are hung outside the screen on either side of goal. When a ball is put into goal, a ball of the same colour is taken off its string. Thus the number of balls remaining on each string denotes, not the number of balls already scored by each side, but the number which still remains to be scored to complete the tale of seven. The scoring of a ball is further announced by two blows upon a drum for one side, upon a gong for the other.

When one side has scored seven balls, it enters the second and final stage of the game. Drum or gong, as the case may be, loudly announces the fact by repeated strokes. That side's hitherto slanting flagstaff is raised to a vertical position, its scoring string stands empty. A banded ball of its colour is thrown into the enclosure from the entrance barrier by an attendant, and is scrambled for by both sides. This is the only ball of the colour now in play. Should it be forced out of play, it is immediately replaced by a similar banded ball thrown into the enclosure in the same manner, and so on. Should it be slung into goal, the game is over, the side of that colour winning the game. In like manner, should the other side score their seventh ball before the opponents score their banded ball, they too are heralded into the second stage of the game, with flag, gong, or drum, and empty scoring string. They, too, have a banded ball of their colour thrown into court, the only one of that colour then in play, also replaced by a similar ball in the event of its being forced out of play. The two sides are in that case again equal, and whichever side scores its banded ball first wins the game. (Until the unsuccessful side scores its seventh ball, however, it still remains in the first stage of the game, and can play with an unlimited number of balls. The winning stroke is announced by loud beating of the gong or drum, and by waving of the flag which distinguishes the winning side. The winners ride out of the enclosure in single file, while the losers dismount and follow on foot, leading their horses,-a picturesque conclusion to a noble and manly game. Should neither side score its banded ball within a given time (half-an-hour usually) from the commencement of play, the game is drawn.

The following minor points deserve notice:-

The importance of the banded ball is always denoted by a change in the whole character of the game. "Goal keepers" are stationed near the goal to defend it. Players are told off to endeavour to obtain and keep possession of the opponents' banded ball. Dodging, slinging from a distance, passing, dribbling, and empounding all add an animation and excitement to the last stage of the game which are somewhat wanting in the first.

Picking up the ball is an art easily acquired; not so the wrist motion necessary to retain the ball in the racket net. This must be the result either of practice or of natural sleight of hand.

The game is sometimes played with three balls instead of seven, either in order to shorten it, or when there is not the full complement of players.

Other games played on horseback are the Samurai Odori, or Warriors' Dance, which may perhaps be best described as a giant quadrille in armour, and the Inu Ou Mono, or Dog Chase, a cruel though not exactly bloody sport, the gist of which is shooting at dogs with blunt arrows. Both are now extremely rare.