THE QUEEN'S TOUR.
(
The Guarded Chessboard)
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:
+---+---+---+---+---+---+---+---+
| | | | | | | | |
| ............................. |
| . | | | | | | | . |
+-.-+---+---+---+---+---+---+-.-+
| . | | | | | | | . |
| . | ..........................|
| . | .| | | | | | . |
Answer:
The annexed diagram shows a second way of performing the Queen's Tour.
If you break the line at the point J and erase the shorter portion of
that line, you will have the required path solution for any J square. If
you break the line at I, you will have a non-re-entrant solution
starting from any I square. And if you break the line at G, you will
have a solution for any G square. The Queen's Tour previously given may
be similarly broken at three different places, but I seized the
opportunity of exhibiting a second tour.
