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.

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.

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.

Howard Staunton Quotes