Page:Amusements in mathematics.djvu/238

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226
AMUSEMENTS IN MATHEMATICS.

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.

329.—THE STAR PUZZLE.

The illustration explains itself. The stars are all struck out in fourteen straight strokes, starting and ending at a white star.

330.—THE YACHT RACE.

The diagram explains itself. The numbers will show the direction of the lines in their proper order, and it will be seen that the seventh course ends at the flag-buoy, as stipulated.

331.—THE SCIENTIFIC SKATER.

In this case we go beyond the boundary of the square. Apart from that, the moves are all queen moves. There are three or four way in which it can be done.

Here is one way of performing the feat:—

It will be seen that the skater strikes out all the stars in one continuous journey of fourteen straight lines, retutning to the point from which he started. To follow the skater's course in the diagram it is necessary always- to go as far as we can in a straight line before turning.

332.—THE FORTY-NINE STARS.

The illustration shows how all the stars may be struck out in twelve straight strokes, beginning and ending at a black star.