6…d5This leaves the KP weak. Usually P—QKt3 is played at this juncture.
8.c5Quite safe now as White can maintain the chain of Pawns by P—QKt4 in reply to P—QKt3 without being liable to have his Pawns broken up by P—QR4, as he would then answer P—QR3.
8…Nbd7An error which costs time.
13.Nf2Obviously if P—Kt3 Black would sacrifice the Kt for two Pawns with an irresistible attack.
19…Nc6The tempting 19....P—B5 was not good on account of 20 B—K2, and if 20....P—KB5; 21 B—B3, 21 Q—Kt4 (of course if 21....Q×P; 22 B—Q4 and wins); 22 P—K4 with the superior game.
20…Qb8Clearly best, for he could not allow White's Kt to enter at QB7.
31…Nd8Not good. He could more safely play 31....B—Q3, for if 32 Kt—K6 ch., 32 B×Kt; 33 Q×B, 33 B×P ch.; 34 K—R sq., 34 B—Kt6; 35 KB—QB4, 35 Q—K sq.; etc.
35…Ra8Black had probably contemplated 35....R×Kt; but found on further examination that White then wins by 36 Q×R, 36 Q×Kt; 37 B×Kt, 37 P×B (best, for if B×B he is mated by Q—Q6 ch.); 38 Q—R6 ch., 38 K—K sq.; 39 Q—R5 ch., 39 K—B sq. (or 39....K—Q2, 40 Q×BP ch.); 40 Q×RP, 40 Kt—K3; 41 R×Kt.
38.Bxg7+This at last breaks into the adverse game and White is bound to win another P afterward.
41.Rxh7Perhaps Kt—B3 was more simple and would have also won a second P, as Black had nothing better than K×R, since White threatened to win a piece by R—K8.
46.f4+This is decisive. See Diagram page 180.
46…Kd4R×P was the best under the circumstances, but of course White would then have replied Kt×KtP, winning slowly but surely. If, however, 46....K—Q4; 47 Kt×BP, 47 Kt—B2; 48 R—B6, 48 Kt—R sq.; 49 Kt—K3 ch., 49 K—K5; 50 Kt—B2 and wins. Obviously if 46....K×P White would answer R—R4 ch. followed by exchanging Rooks and Kt×KtP.
William Steinitz, The Modern Chess Instructor (1889) · Public domain · source