Another common form of trap is to get a player into such a position in the end game, when he has only one or two men, that he cannot get to the king row without being caught; sometimes because he is driven to the side of the board by the man following him, and sometimes because the man meeting him can head him off. The adversary can do this only when he has “the move.”
Theory of the Move. When the position is such that you will be able to force your adversary into a situation from which he cannot escape without sacrificing a piece or losing the game, you are said to have the move; and if he does not change it by capturing one of your men he must lose the game. As the move is often of the greatest importance in the end game, every checker-player should understand its theory, so that he may know when it is necessary to make an exchange of men in order to secure the move, and when he should avoid an exchange which would lose it. The move is only important when the number of men on each side is equal.
In order to calculate the move, the board is supposed to be divided into two systems of squares, sixteen in each. The first system is formed by the four vertical rows running from your own side of the board, as shown by the dotted lines in Diagram No. 8. The second system runs from your adversary’s side of the board, as shown in Diagram No. 9.
FIRST SYSTEM.
No. 8.
SECOND SYSTEM.
No. 9.