king, as that your adversary, by bringing forwards a rook or a bishop, might check your king if she were not there, for you could hardly save her, or perhaps at best must sacrifice her for an inferior piece ; as for example: place the white Icing on 61, the queen on 53 ; the black king on 4, and the rook, on 16; which last, if moved to 13, must be taken by the white queen, who in return would be taken by the black king, because the white queen could not otherwise be moved without putting the king on check to the black rook.
14. Let not your adversary's knight fork your king and queen, or king and rook, or queen and rook, or your two rooks, at the same time ; for in the two first cases, the king being forced to go out of check, the queen or the rook must be lost; and in the two last a rook must be lost, at best, for a worse piece. Place the white queen on 5, the rook on 7, and a black knight on 37• The latter piece, if moved to 22, will fork both the queen and rook, and consequently one of them must be lost for the knight.
15. Take care that no guarded pawn of your adversary's fork two of your pieces : knights and rooks are particularly liable to this mode of attack ; also guard against either a check by discovery, or a stale- mate.
16. When the kings have castled on different sides of the board, attack with the pawn you have on that side where the adversary has castled, advancing the pieces, especially the queen and rooks to support them ; aud if the adversary's king have three pawns on a line in front, he should not stir them till forced to it.
17- Endeavour to have a move in ambuscade ; that is, place the queen, bishop, or rook behind a pawn, or a piece, in such a manner, as that, upon