“Yes, I remember that. It comes into puzzles and things of that sort.”
Westenhanger thought for a short time without saying anything.
“One knight gives a tip to the other,” he mused at last. “There’s only one tip worth having in chess: and that’s how to checkmate your opponent.”
He looked over the board once or twice.
“That’s it!” he exclaimed. “One of these knights can mate the black king without the help of any other piece if he moves this way. One—two—three—four moves!”
He moved the white knight from the knight’s square successively to the squares number 1, 2, 3, and 4 in the diagram.
“That gives checkmate. Now let’s try the other knight.”
He tried a move or two.
“This second knight can’t get a mate in four moves by any chance. That looks all right, doesn’t it?”