There are one or two peculiar movements which are allowed only under certain conditions. One of these is Castling. If there are no pieces between the King and the Rook, and neither piece has been moved, the King may be moved two squares toward the Rook, and at the same time the Rook may be brought round to the other side of the King. The movement must be made with both hands, each manipulating a piece. In the position shown in Diagram No. 6, for instance, the King could castle on either side, with the King’s Rook, or with the Queen’s Rook:—
No. 6.
If an adverse piece commands the square that would be passed over by the King in castling, the move is not allowed; because a King must not move into check, nor cross a square that is checked by an adverse piece nor castle out of check.
In Diagram No. 7 the position that would result from castling with the Queen’s Rook is shown by the black men.
No. 7.
Queening Pawns. If a passed Pawn succeeds in reaching the last or eighth square on any file, the player to whom the Pawn belongs may call it anything he chooses, from a Queen to a Knight. If the piece he chooses has already been captured, it must be replaced on the board, and on the square occupied by the Pawn, which is then removed. If not, some other piece must be put upon the board as a marker; a Rook upside down, or a Pawn with a ring on it, may represent a second Queen.
OBJECT OF THE GAME. If all the pieces could be captured, the object of the game might be to clear the board of the adversary’s men, as in Checkers; but the peculiarity of Chess is that one piece, the King, cannot be captured, and the object is to get the adverse King in such a position that he could not escape capture if he were a capturable piece. When that is accomplished the King is said to be mated, and the player who first succeeds in giving mate to the adversary’s King wins the game, regardless of the number or value of the pieces either side may have on the board at the time the mate is accomplished.