312.--THE FIVE CRESCENTS OF BYZANTIUM.

When Philip of Macedon, the father of Alexander the Great, found himself

confronted with great difficulties in the siege of Byzantium, he set his

men to undermine the walls. His desires, however, miscarried, for no

sooner had the operations been begun than a crescent moon suddenly

appeared in the heavens and discovered his plans to his adversaries. The

Byzantines were naturally elated, and in order to show their gratitude

they erected a statue to Diana, and the crescent became thenceforward a

symbol of the state. In the temple that contained the statue was a

square pavement composed of sixty-four large and costly tiles. These

were all plain, with the exception of five, which bore the symbol of the

crescent. These five were for occult reasons so placed that every tile

should be watched over by (that is, in a straight line, vertically,

horizontally, or diagonally with) at least one of the crescents. The

arrangement adopted by the Byzantine architect was as follows:--

[Illustration]

Now, to cover up one of these five crescents was a capital offence, the

death being something very painful and lingering. But on a certain

occasion of festivity it was necessary to lay down on this pavement a

square carpet of the largest dimensions possible, and I have shown in

the illustration by dark shading the largest dimensions that would be

available.

The puzzle is to show how the architect, if he had foreseen this

question of the carpet, might have so arranged his five crescent tiles

in accordance with the required conditions, and yet have allowed for the

largest possible square carpet to be laid down without any one of the

five crescent tiles being covered, or any portion of them.

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