THE MOVE AND ITS VAGARIES.

Otago Witness, Issue 2668, 3 May 1905, Page 62

THE MOVE AND ITS VAG ARIES.

By James Mttlvey.

No. 111. There are quite » number of ways of effecting an exchange of one for one, of which the following are a few examples ; and it will be observed that in some instances the. "move" is changed, and in others it is not. The student will also notice in & few of the positions that neither of the capturing pieces is removed from the board, notwithstanding which the effect on the "move" is not always the same. The following rule, however, seems to cover all the different phases of an exchange of one for one: — "In order to alter the 'move' b^ a single exchange, it is essential that the capturing pieces should, at the time of capturing, be in different systems. If they capture from the same system the "move' will remain unaltered." A careful study of the examples given will show that this is correct. For convenience I White System. Buck System.

shall call the system having the Black squares at the bottom the Black System, and that with the White squares the White System. No. 1. White men on 20, 15. Black men on 3, 7. Black plays 7 11, 15 8. 3 10 and gains the "move?" one of the capturing pieces being in the White Systenij and the other being in the jJJagk .- . '_

No. 2. White men on 29, 25, IS, 13. Black men on 1. 2, 6, 9. Black plays 9 14, 18 9, 1 5, 25 22, 5 14, and White now has the "move." Continue 29 25, 6 9, 13 6, 2 9, and Black regains the move and wins. No. 3. White men on 19, 16. Black men on 8, king 23. White to play. He has the "move," 7mt the position is hopeless. Play 16 12, 23 16, 12 3, ! 16 11, and Black has gained the move, although i both capturing pieces remain. No. 4. White man on 18, king 15. Black man on 8, king 22. White to play. White has the "move," but supposing he exchanges by 15 11, he will lose it, whether Black takes 8 15 or 22 15, the effect on the "move" being the same, although, in one instance one of the v capturing pieces ia removed and in the other neither is. It will thus be seen that Dunne's rule is nofc correct. No. 5. White mm on 16, king 25. Black man on 17, king 24. Black plays, but White has the "move." Suppose Black plays 24 20, then by applying the rule given above, it is at once apparent that White will lose the "move" if he goes 25 21, and allows Black to capture 20 11, as Black captures from the White System and White ~from the Black one. Instead of 25 21. play . ]6 11, and if Black now plays 20 16, White can play 25 21, 16 7, 21 14, and retain the "'move," as both captures are made from the White System. No. 6. White men on 32, 30, 27. 24. Black men on 15, 17. 20, 22. White, playing first, has the "move" — 27 2-3,-20 27, 23 18, 27 31, 18 11, and White retains the "move,' both captures being made from the Black System. No. 7. White men on 24. 23, 19, 17. 14. Black men on 1. 2, 7, 10, 12. Black to play. White has the "move.'' Continue 7 11, 14 7. 11 16, 7 3, 16 20 19 15. 20 27, and Black now has the "move," White having; captured from the WEite and Black from the Black System. Instead of playing 7 3 at the fourth move of White plays 24 20. 2 11, 17 14, 1 6. and White is blocked owing to Black gaining the "move,' on account of the captures being made from different systems. There are numerous other ways of making a single exchange, but the foresroing examples are sufficient to prove that *he only element which effects the "move" is a consideration of the systems from which the captures are made.

(To be continued.)