THE MOVE AND ITS VAGARIES. (Concluded.)

Otago Witness, Issue 2578, 12 August 1903, Page 59

THE MOVE AND ITS VAGARIES.

(Concluded.)

By James Muxvey, Gore.

As I pointed out in former articles, it is the removal of the men from the different systems which causes the alteration in the "move." A treble exchange, or three for three, removes six men from the board, of which five may be in one system, and one in tho other,, or four and two, or three and three respectively, or the whole of them may be removed from one system. If the removal of the men were the only thing we had to consider, it would be comparatively easy, to decide tho effect on the

"move, ' but this is not all. During the progiess of the exchange there may be a number 01 waiting moves, which must not be overlooked, or we will find our calculations of no avail. After ths exchange is completed, there is another important point which must not be left out, and that >s whose turn to play will it be? Your own or your opponent's? There are thus three elements to be conpJdered, but these may be reduced to one, in order to simplify matters. We will suppose it is our turn to play, then we will calculate up to the first move we make after the exchange is completed. Our first consideration is the six men actually removed from the board, of which the mimbers in each system will either be both even or both odd. As both systems are the same as regards odd or even, it is only necessary for us to count the men removed from one system only. Our second consideration is the number of waiting moves Each waiting move is piayed from one system into the other, and therefore alter 3 the total in both systems from odd to even, or vice versa. We will, therefore treat each waiting move as a piece removed from one system by the exchange. It is only necessary to count the waiting moves mado by pieces which are not removed from the board. Those moves made by pieces which aie taken off during the progress of 'the ex- : change do not affect our calculations in any way. If it will be our own turn to play after the exchange is completed, well and good, but if our opponent's, then it will be necessary to add another to our total, as his move alters the to'al m the different systems. I have explained -the details very fully, in order that even the beginner raav grasp them without tho slightest difficulty. To reduce these to concrete form, we can make tho following lule to govern this exchange—or in fact any species of exchange, no matte.- how many pieces aside are removed: — "Count the number of pieces removed fiom one system only, and then add to them the number of single or waiting moves, including your opponent's if it is his turn to piay after the exchange is completed, but do not inc'.ude any waiting moves made by pieces removed from the board. If the grsnd total is even, the 'move' will not be altered ; if odd it will be." Although there are hundreds of different niodo3 of effecting a treble exchange, there are only 16 main governing conditions, and in each instance one of these will be employed. They | are as follows: — First, an exchange purs and ; simple, in which an even number of men are removed from each system, with no waiting moves, and your own turn to play after the exchange. Second, ditto; but your opponent's turn to play afterwards. The third and fourth are similar to the first and second respectively, except thai an odd number of men <s removed from each system. The conditions are similar [ in the fifth, sixth, seventh, and eighth respec- | tively, except that in each instance there 13 one waiting move. In the next four styles j there are two waiting nnoves, and in the last four there are three waiting movo3. It would occupy too much space to give examples of | each, but players can easily set up examples I for themselves. } When wo understand the principles governing the alterations of the move, we might further simplify the rule by leaving out all even r umbers. For instance, if the number of men removed from one system is even, or if there is an even number of waiting moves, they need rot be included in our calculation, as even numbers do not. alter tho "move" ; it is only liecessary, therefore, to count the odd numbers, but in the examples giveu below we will apply tlio rule in its entirety. Black moves fust in all examples. No. 1. Black men on 1, 6, 9, 15, 19. White men .on 30, 29, 28, 26, 17. White has the "move," and we wish to decide ••■•hat effect the exchange by 9 14, 17 10, 19 23, •2G 19. 15 24, 28 19, G 24 will have on it. We will first count the number of men which will 1>? removed from one of the systems. Take the White system, and we find that the man on 15 is the only one affected, there are no waiting moves, but it will be White's turn to play after the exchange, and we muat, therefore, add one to tho man removed, which makes the tcfal 2, which is an .even number. White will thus retain the "move." No. 2. Black men on 1, 2, 5, 9, 13. White men on 31, 29, 23, 22, 15. Black has the move, and if we exchange t3 17, 22 6, I 26, 31 22, what will the result be? There are no waiting moves, and it will be Black's turn to play afterwards, so we need oi.ly count the pieces removed from one system. There are two men removed from the Black system, those on. 1 and 9. The number being oven, Black retains the "move." No. 3. Black on 1. 2, 6, 10, 11. White men on 29, 27, 20, 18, 12. What effect will the exchange by 11 16. 20 11, 2 7, 11 2, 1 5, 2 9, 5 32 have on the "move," which is iii tho possession of White at present? There is one piece (that on 6) removed from ths White system, one waiting move (1 5), and White's turn to play afterwards. Our total is, therefore, three, which is an odd number. Black gains the "move." No. 4. Exactly the same position as No. 3, except that a black man is on 7 instead of 2. Black has the "move," and by exchanging 11 IG. etc., he retains it, as our total is even, there being two man removed from the White system, plus one wailing move, plus White's move. No. 5. Black men on 2, 7, 14, 16, king 13. White men m 29, 28, 27, 26, king 3. Black has the "move," and retains it by playing 16 20, cs our total is even, there being three men removed from the Black system, plus one waiting move. No. 6. Black men on 2, 7, 8, 14, king G. White men on 32, 29. 27, 26, 12. White has the "move." If Black plays 6 9 and 9 13, White will retain the "move," our total being even. There are three men removed from the Black system, plus tlio two v/aiting moves, plus White's move afterwards.

Black men on 5, 7, 8, 14, king 9. White men on 32, 29, 27, 26, 12. Black ha 9 the "move," but will lose it if he plays 9 13, 12 3, 13 17, 3 10, 17 13, 10 17, 13 24, as we have an odd total— three men removed from the Bla-ck system, plus three waiting moves, plus White's move. The above examples are sufficient to show the detailed method of calculating th^effect of a treble exchange on the "move. ' When the principles are undeistood, the simpler methods may bo adopted.