132 Geometrical Problemsmoves, to compartment F. You can move the counters one at a time to any
compartment, but may never place a counter on one that bears a smaller
number than itself. Thus, if you place I on Band 2 on C, you can then place
1 on 2, but not 2 on 1.
- MAGIC FIFfEEN PUZZLE
This is Sam Loyd's famous 14-15 puzzle, in which you were asked to get
the 14 and 15 in their proper order by sliding the blocks about in the box. It
was, of course, impossible of solution. I now propose to slide them about un-
til they shall form a perfect magic square in which the four columns, four
rows, and two diagonals all add up to 30.CD ®
@
®0) ® (j)
®® @ @ @
@ @ @
It will be found convenient to use numbered counters in place of the
blocks. What are your fewest possible moves?- TRANSFERRING THE COUNTERS
Place ten counters on the squares of a chessboard as here shown, and
transfer them to the other comer as indicated by the ten crosses. A counter
may jump over any counter to the next square beyond, if vacant, either
horizontally or vertically, but not diagonally, and there are no captures and
no simple moves-only leaps.
Not to waste the reader's time it can be conclusively proved that this is im-
possible. You are now asked to add two more counters so that it may be done.