Chess no. 346

PHILIDOR n

A. Ellerman (3rd prize, Good Companions, 1917). White to play and mate in two moves; solution next week.

Solution to no. 345 (Hartong): B - B 3, threat 2 Kt - Q 2 eh, P x Kt; 3 Q - Q 3 mate. (a) 1 ... Kt -B 5; 2 Kt x P ch, B / Kt; 3 B- B 5. (b) 1 . . . P - B 5; 2 B - B 5 ch. Kt x B; 3 Kt x P. Complex half-pin problem: Black defences inter- fere with the half-pin on White king and free the B and Kt to exploit the half-pin by rook on Black's king.

Fair exchange ?

Games in which one exchanges different but more or less equivalent combinations of pieces for each other, e.g. R and two Ps for B and Kt, have a special interest arising from the rival merits of the opposing combinations. In particular, the ex- change of Q for its various equivalents, e.g. Q for R, B and one or two Ps or Q and P for two Rs or Q for three minor•pieces, gives rise to difficult and interesting games. I think that it is a sound general principle that the queen will do well in loose positions where there is a good deal of un- protected material—she can so often pick some of it up; however, if the opponent can consolidate, the piece combinations (especially the three •minor pieces) will usually win. Here is an amusing— though not very good—game in which the minor pieces are far too strong.

White, Kolos. Black, Anoshin. Opening. Three Knights. (USSR, 1956.)

1P-K4 P - K 4 2 Kt B 3 Kt -Q B 3 3 Kt - B 3 P - K Kt 3. This is used sometimes by players who wish to avoid the drawing tendencies of the Four Knights, but is rather in White's favour. 4 An aggressive alternative is 4 P - Q 4, P x P; 5 Kt -Q 5 with good chances; the text is fairly innocuous.

K 2

5 -.la 3 K Kt t -K 2

6 B -K Kt 5 P- K R 3. A weakening move he cannot well avoid.

7 B- K 3 P- Q 3 7 . . . Kt - R 4 eliminating the K • B is better as this would reduce the danger of attack against the king should be play 0 -0. 8 Q- Q 2?. . an indifferent reply; better P- Q R 3 (against Kt - R 4). or Q - IC 2. s . . P - B 4!

9 Q - K 2 P - B 5

10 B - Q 2 B - Kt 5. While Kt - R 4 is probably still

best, this should also be all right.

11 P - K R 3 B- R. 4. It is rather better to play (a) 11 . . Kt - Q 5; 12 Kt x Kt!, B x Q; 13 Kt - K 6, B- R 4! (best); 14 Kt x Q!, R X Kt or (b) 11 B x Kt; 12 Q X B, Kt - Q 5. However, he does not realise his danger, tries for too much and is slaughtered,

12 P-K Kt 4 P xPe.p. 13 P x P Kt - Q 5? He must play 13 .. B x Kr;

14 Q x B, R - K B 1; 15 Q - Kt 2 when be still has only a little the worse of matters.

14 Kt x Kt! B x Q 14 . . P x Kt; 15 P - K Kt 4. P x Kt; 16 B X P is better but leaves White with a markedly superior game, e.g. 16 . B x B; 17 P x B,

Q - Q 2; 18 P x B or 17. . . P; 18 Q x B.

15 Kt -K 6 Q - Kt 1. And not 15 . . . B - R. 47;

16 Kt XQ R XKt; 17 P-K Kt 4!

16 Kt X 13 ch K - Q 2 17 K X

18 Q R-B K B I R - B I

19 B - K 6 ch K - B 2

20 B -B 7! . . A neat finesse. 20..R-R 1 21 B -.Ks 3! K - Kr 3. White threatened a winning pin by R - B 7. 22 R - B 7 Q-Q 1

23 Kt - K 6 Q - K 1 24 Kt - R 4 ch K - R 3 25 Kt - B 7 mate