[Illustration]
If the reader should cut out the above diagram, fold it in the form of a
cube, and stick it together by the strips left for that purpose at the
edges, he would have an interesting little curiosity. Or he can make one
on a larger scale for himself. It will be found that if we imagine the
cube to have a complete chessboard on each of its sides, we may start
with the knight on any one of the 384 squares, and make a complete tour
of the cube, always returning to the starting-point. The method of
passing from one side of the cube to another is easily understood, but,
of course, the difficulty consisted in finding the proper points of
entry and exit on each board, the order in which the different boards
should be taken, and in getting arrangements that would comply with the
required conditions.