217.--THE TWICKENHAM PUZZLE.

[Illustration:

( I ) ((N))

( M ) ((A))

( H ) ((T))

( E ) ((W))

( C ) ((K))

( )

]

In the illustration we have eleven discs in a circle. On five of the

discs we place white counters with black letters--as shown--and on five

other discs the black counters with white letters. The bottom disc is

left vacant. Starting thus, it is required to get the counters into

order so that they spell the word "Twickenham" in a clockwise direction,

leaving the vacant disc in the original position. The black counters

move in the direction that a clock-hand revolves, and the white counters

go the opposite way. A counter may jump over one of the opposite colour

if the vacant disc is next beyond. Thus, if your first move is with K,

then C can jump over K. If then K moves towards E, you may next jump W

over C, and so on. The puzzle may be solved in twenty-six moves.

Remember a counter cannot jump over one of its own colour.

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