+---------------------------------------+ 8 | #R | | #B | #Q | | #R | #K | | |---------------------------------------| 7 | #P | #P | | #Kt| #B | #P | #P | | |---------------------------------------| 6 | | | #P | | | #Kt| | #P | |---------------------------------------| 5 | | | | #P | | | | | |---------------------------------------| 4 | | | | ^P | | | | | |---------------------------------------| 3 | | | ^Kt| ^B | ^B | ^Kt| | | |---------------------------------------| 2 | ^P | ^P | ^P | ^Q | | ^P | ^P | ^P | |---------------------------------------| 1 | | | ^K | ^R | | | | ^R | +---------------------------------------+ a b c d e f g h DIAGRAM 51. The play might proceed like this: (1) P-g4, P-g5; (2) Bxg5, Pxg5; (3) Qxg5+, K-h8; (4) Q-h6+, K-g8; (5) P-g5, Kt-e4; (6) Ktxe4, Pxe4; (7) P-g6, Pxg6; (8) Qxg6+, K-h8; (9) R-g1, etc. Ordinarily both players castle on the same side of the board so that neither of them can advance his Pawns in an attack against the opposing King without weakening his own King's position. Only if a player holds more territory and has a greater number of pieces on the King's wing than the opponent he can embark on an attack which involves an advance of the Pawns in front of his King. Diagram 52 offers a typical example. +---------------------------------------+ 8 | #R | | | | | #R | #K | | |---------------------------------------| 7 | | | #Q | #B | #B | #P | #P | #P | |---------------------------------------| 6 | #P | | | #P | | #Kt| | | |---------------------------------------| 5 | #Kt| | #P | ^P | #P | | | | |---------------------------------------| 4 | | #P | | | ^P | | | | |---------------------------------------| 3 | | | ^P | | ^B |^Kt | | ^P | |---------------------------------------| 2 | ^P | ^P | ^B | | | ^P | ^P | | |---------------------------------------| 1 | ^R | | | ^Q | ^R | ^Kt| ^K | | +---------------------------------------+ a b c d e f g h DIAGRAM 52.
Black has a preponderance on the Queen's side, while White has more mobility for his pieces on the King's side. Considering that Black cannot easily throw his men over to the King's wing, White can risk to loosen his Pawns on this wing without fearing that Black will be able to obtain a foothold on the weak points which are necessarily created by the advance of the Pawns in White's camp. White will start the attack with (1) P-g4 and (2) Kt-g3. Then he threatens to occupy the dominating square f5 with his Knight, and Black has hardly any other move than P-g6; for if he permits Ktf5 with the view to exchanging the Knight with his Bishop, he opens the g-file for White's Rooks. P-g6 on the other hand enables White to open the h-file by advancing the h-Pawn after the necessary preparations such as K-g2, R-h1, P-g5, etc. In the vast majority of games files for the Rooks are not opened on the side but in the center of the board, as was explained in the discussion of the openings. The many advantages arising from the control of a center-file by the Rooks will be more fully analyzed in the illustrative games. Generally speaking it is easier to get the two Rooks into cooperation in the center than on the side of the board. This cooperation--usually effected by doubling in one file--is naturally very important and it is the main reason why it is desirable to castle as early as possible. Between the Rooks of a player who is prevented from castling there are, so to speak, no natural lines of communication and it takes so long to create artificial ones that in most cases the opponent can, in the meantime, force a victory through the combined efforts of his Rooks. Diagram 53 gives an example.