320.--THE ROOK'S TOUR.

[Illustration:

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The puzzle is to move the single rook over the whole board, so that it

shall visit every square of the board once, and only once, and end its

tour on the square from which it starts. You have to do this in as few

moves as possible, and unless you are very careful you will take just

one move too many. Of course, a square is regarded equally as "visited"

whether you merely pass over it or make it a stopping-place, and we will

not quibble over the point whether the original square is actually

visited twice. We will assume that it is not.

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