THE MOVE AND ITS VAGARIES.

Otago Witness, Issue 2667, 26 April 1905, Page 60

THE MOVE AND ITS VAGARIES.

By James Mtjlvey.

No. 11. The next step to be able to discover, at any stage of the game, which player has possession of this very important factor, the move, as it is constantly passing from one to another as the pieces are exchanged and removed from the board. There are several ways of doing thia, but the simplest is to divide the board into two systems of squares, consisting of four columns each — viz., those columns with a white square at the bottom to form one system, and those with a black one the other, as in the two diagrams given below: ' ' First System. " ' ' Second S ystem".

Then count the pieces in one system only (either will do). If the number be an odd one. and it cs your turn to play, you have the "move" ; if even, your opponent has it. The following little rhyme should be committed to memory by the learner, in order to fix this rule in his mind: — When it is your turn to play, Systems one to four survey ; If the number odd should prove You will find you have the move, But if even, then 'tis clear, You will have a block to fear. Example : —

Black to move and win.

By applying the rule in this position, it will at .once be seen that the number of pieces is odd.: therefore, Black has the "move," and is enabled to block his opponent's pieces, and force the win thus:— l 5, 28 24, 48, 24 19. 8 11, 29 25, 59, 25 22, 9 13. White must now lose a piece and the game. An exception to the above rule arises when one of the pieces is in an .unplayable position, as in the following example: — White men on 24, 17, 5; Black men on 1, 2, 8. White to play. In this position White has the "move" in theory only, as in practice it is "Black that does N^he blocking. In cases of this kind it is necessary io reverse the rule. The following is a gtfod example o£ the practical utilisation of the knowledge that the forcing of an opponent's piece on to an unplayable square alters the move: — .

Black: kings 3, 21. White: 29, king 4.

Black to play and. -win.

It is at once apparent that Black has not got the "move," and a carefui study of the position shows that he cannot force an exchange, and so alter it, but he forces the White man into an unplayable position, and so gains the move on the other piece as follows: -21 17, 29 25, 17 14, 25 22, 14 9, 22 17. 9 6, 17 13, 6 1, 13 9, 3 7, 4 8, 7 2, 9 5, 2 7, and Black wins.

This phase is not mentioned in several of the books, including Dunne's Guide, and there is another which is also neglected, and that is •when it so happens that a player's own pieces stop the full development of his -game tnus : — White men on 32, 23, 20, 19; Black men on 1. 6, 11, 12. White to play. It will be seen that "White has The move in theory, but owing to the j>iece on 32 being unable to get out, its possession is of no use, and Black wins as follows: — 23 18, 6 10, 32 27, 1 6, 27 23, 6 9. and wins. The above is a rather simple position, but it serves to illustrate my point, showing that it is not always an advantage to have the "move." The idea might come up with any number of men on tlie board. I remember losing a game once by being blocked in this •way, when 1 ixad sis. or seven pieces on the board, although I had the "move" in theory. It is therefore advisable not to take it for granted that because you have the "move" you will always block the other fellow. It is in end-game play that a thorough knowledge of the "move" is absolutely indispensable. Tile first thing an expert does before he starts to study an end-game problem is to see which side possesses it. The following position shows the working of the theory very neatly : —White man on 28, king on 31 ; Black man on 7,. king on 23. Black to play and win. BlaeJ^has the move, and -it is possible to block White if played correctly. A short study will show th»t you must allow the white man to crown, and it is also evident that you cannot ciown the black man and bring it back in time to prevent White from getting into the double corner. The secret cs to make the man take the king's place in blocking the white king. and then impri=on the white man with the black king as follows:— 7 11, 28 24, 11 15, 2i 20. 15 18, 20 16, 23 19, 16 11, 18 23. and the end is *n view.

If it should be desirable to alter the "move." the hooks tell us that it can be effected by an exchange of odd pieces, such as one for one, or three for three. Dunne's Guide goes further, and says that the lule will not apply unless one of the capturing pieces be removed from the board. Examples are given proving the above rules to he correct, aud there the explanation ends. Unfortunately, exceptions can be found in every one of them. In the first place, it does not always follow that an exchange of odd pieces will alter the "move." On the other hand, the "move" may be altered by the exchange of any number of pieces, it feeing immaterial whether the number be odd or even, the result whollj depending upon the manner in which tlie exchanges are made. Nor is it necessary th.it one of the capturing •oieces be removed, as the "move" may be altered without the removal of either.

(To be continued.)