The Queen is by much the most powerful of the forces.

The Bishop moves diagonally forwards or backwards, to the extent of the Board.

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.

The Queen is by much the most powerful of the forces.

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.

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.

A player is said to have the opposition when he can place his King directly in front of the adverse King, with only one square between them. This is often an important advantage in ending games.