[Illustration]
A pretty symmetrical solution to this puzzle is shown in the diagram.
Each of the four kangaroos makes his little excursion and returns to his
corner, without ever entering a square that has been visited by another
kangaroo and without crossing the central line. It will at once occur to
the reader, as a possible improvement of the puzzle, to divide the board
by a central vertical line and make the condition that this also shall
not be crossed. This would mean that each kangaroo had to confine
himself to a square 4 by 4, but it would be quite impossible, as I shall
explain in the next two puzzles.