(related to Problem: The Ruby Brooch)

In this case, we were shown a sketch of the brooch exactly as it appeared after the four rubies had been stolen from it. The reader was asked to show the positions from which the stones "may have been taken;" for it is not possible to show precisely how the gems were originally placed because there are many such ways. But an important point was the statement by Lady Littlewood's brother: "I know the brooch well. It originally contained forty-five stones, and there are now only forty-one. Somebody has stolen four rubies, and then reset as small a number as possible in such a way that there shall always be eight stones in any of the directions you have mentioned."


The diagram shows the arrangement before the robbery. It will be seen that it was only necessary to reset one ruby — the one in the center. Any solution involving the resetting of more than one stone is not in accordance with the brother's statement, and must, therefore, be wrong. The original arrangement was, of course, a little unsymmetrical, and for this reason, the brooch was described as "rather eccentric."

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Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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