Illustration of Small Multiples – Magic Knight Tours

I found a good example of using small multiples (Tufte, Visual Display of Quantitative Information, p.170 and elsewhere) in an article on slashdot today.

The subject example concerns the computation of “Magic Knight’s Tours”. A Knight’s Tour is a set of standard moves of a Knight piece on a chessboard, such that each square on the board is visited exactly once. Each square is numbered in the sequence of moves, so you have the numbers 1 through 64 on a standard 8×8 chess board. A Knight’s Tour is called a Magic Knight’s Tour if the resulting numbers on the squares form a magic square. It turns out there are 140 possible Magic Knight’s Tours.

The most interesting graphic is one that shows all 140 combinations in a single graphic, enabling you to see the beginning and ending point of each tour, and to observe certain patterns in the tours.

A candidate for Beautiful Evidence?