]

This is quite a fascinating little puzzle. Place eight bishops (four
black and four white) on the reduced chessboard, as shown in the
illustration. The problem is to make the black bishops change places
with the white ones, no bishop ever attacking another of the opposite
colour. They must move alternately--first a white, then a black, then a
white, and so on. When you have succeeded in doing it at all, try to
find the fewest possible moves.

If you leave out the bishops standing on black squares, and only play on
the white squares, you will discover my last puzzle turned on its side.


328.--THE QUEEN'S TOUR.

The puzzle of making a complete tour of the chessboard with the queen in
the fewest possible moves (in which squares may be visited more than
once) was first given by the late Sam Loyd in his _Chess Strategy_. But
the solution shown below is the one he gave in _American Chess-Nuts_ in
1868. I have recorded at least six different solutions in the minimum
number of moves--fourteen--but this one is the best of all, for reasons
I will explain.

[Illustration:

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