Don Berg
                                                                12/5/95
           SOLUTION TO THE 11TH HOUR FOUR KNIGHTS PUZZLE

 It helps to number the chessboard squares as shown, and to imagine the
 squares connected in a line according to the allowed knight movement:

      Chessboard Square Layout         Linear Square Layout
    ______                      
   |      |                                  
   |  3   |                                      7A
   |______|______ ______ ______                  |
   |      |      |      |      |                 6A
   |  6A  |      |  4   |  1   |                 |
   |______|______|______|______|                 5A
   |      |      |      |                        |
   |  5   |  2   |  7A  |               1--2--3--4--5
   |______|______|______|       
   |      |      |                      
   |      |  5A  |              
   |______|______|                      


 The goal is to move the knights from the initial linear square position
 to the final linear position shown below:
        Initial Position               Final Position
                  x                             x
                  |                             |
                  x                             x                         
                  |                             |
                  x                             x                         
                  |                             |                                 
         W--W--B--x--B                 B--B--W--x--W


 This can be accomplished in exactly 40 moves as follows:
      COLOR             MOVES
        B       3  -> 4  -> 5A -> 6A -> 7A
        W       2  -> 3  -> 4  -> 5A -> 6A
        W       1  -> 2  -> 3  -> 4  -> 5A
        B       5  -> 4  -> 3  -> 2  -> 1
        W       5A -> 4  -> 3  -> 2
        W       6A -> 5A -> 4  -> 3
        B       7A -> 6A -> 5A -> 4  -> 5
        W       3  -> 4  -> 5A -> 6A
        W       2  -> 3  -> 4  -> 5A
        B       5  -> 4  -> 3  -> 2
        W       5A -> 4  -> 3
        W       6A -> 5A -> 4  -> 5