13 APRIL 1956, Page 35

Chess

BY PHILIDOR

No. 45 Specially contributed by BLACK (10 men)

Solution to last week's problem by Weenink: Kt–Q 4!

waiting. 1 . . • B–B 2; 2 Q X Kt.

1 . . B else; 2 Kt–Kt 6. 1 . . . R x Q; 2 Kt x R. 1 . . R–B 8; 2 Bx Kt. 1 • • • mull: (6 men) Kt x Kt; 2 Q–B 4. 1 . . . Kt–B 4; 2 Q–R 1. 1 ... Kt-.Q 7; 2 Q–B 6. Remarkable variety and scope considering the comparatively few pieces employed.

CHESS PROBLEMS

From time to time I get puzzled letters from readers complaining gently of the jargon used in solutions given to the chess problems: an article, therefore, on what chess problems are about and on some of the commoner ideas might not be out of place. Chess notation I cannot explain in an article because of the stupefying boredom of the subject, but any elementary book—e.g., Golombek's excellent Penguin, The Game of Chess—will clear this up.

The object of a problem is not to ahoy) how one player or other can win; it is to illustrate some idea—often a geometrical one—on the chess board, this idea being the 'theme' of the problem. A problem is, in fact, a minor work of art, where a game is a struggle. Take, for example, a 'half-pin' theme: here we have two Black pieces intervening between a White piece and the Black king—each of these is free to move, but if either does so, the other is then pinned. In a half-pin problem, then, the various 'thematic' Black defences will consist in his moving one of these pieces to prevent a threa- tened mate, whereupon White will take advan- tage of the other piece being unable to move to give a new mate.

Another type of problem is the 'waiter,' where White's initial move threatens nothing, but Black must move—and all moves are fatal. A very popular development from this is the 'mutate' or 'change-mate' problem. Here the initial position is such that if White did not need to move at all Black would have to make a fatal move (the various mates that would follow from his moves are called 'set' mates, being in the position as set); White, however, cannot find a move which leaves the position, essentially un- altered,and has to play a move which, while making no threat, again leaves Black in a position where all his moves are fatal, but some or all of . the resulting mates are different from those arising from original position (these are the 'changed mates').

Understanding of some of these basic ideas adds greatly to the pleasure to be got from problems. I hope this very sketchy introduction will therefore have done something to' increase readers' enjoyment.