The Queen is usually reckoned equal, in average situations, to two Rooks and a Pawn, but towards the end of a game she is hardly so valuable as two Rooks.

If, during the course of the game, it be discovered that any error or illegality has been committed in the moves of the pieces, the moves must be retraced, and the necessary correction made, without penalty.

In Castling, the King must be moved first, or before the Rook is quitted. If the Rook be quitted before the King is touched, the opposing player may demand that the move of the Rook shall stand without the Castling being completed.

Each player, it will be observed, has eight superior Pieces or officers, and eight minor ones which are called Pawns; and, for the purpose of distinction, the Pieces and Pawns of one party are of a different color from those of the other.

It is the duty of the Umpire to determine all questions submitted to him according to these laws, when they apply, and according to his best judgment when they do not apply.

When a Piece or Pawn is in a situation to be taken by the enemy, it is said to be en prise. To put a piece en prise, is to play it so that it may be captured.

A Rook is of the value of five Pawns and a fraction, and may be exchanged for a minor Piece and two Pawns. Two Rooks may be exchanged for three minor Pieces.