In a public place in Rome there once stood a prison divided into
sixty-four cells, all open to the sky and all communicating with one
another, as shown in the illustration. The sports that here took place
were watched from a high tower. The favourite game was to place a
Christian in one corner cell and a lion in the diagonally opposite
corner and then leave them with all the inner doors open. The consequent
effect was sometimes most laughable. On one occasion the man was given a
sword. He was no coward, and was as anxious to find the lion as the lion
undoubtedly was to find him.
[Illustration:
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| L |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
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| C |
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+-- --+-- --+-- --+-- --+-- --+-- --+-- --+-- --+
]
The man visited every cell once and only once in the fewest possible
straight lines until he reached the lion's cell. The lion, curiously
enough, also visited every cell once and only once in the fewest
possible straight lines until he finally reached the man's cell. They
started together and went at the same speed; yet, although they
occasionally got glimpses of one another, they never once met. The
puzzle is to show the route that each happened to take.