The Histories · 7.60

Now of the number which each separate nation supplied I am not able to give certain information, for this is not reported by any persons; but of the whole land-army taken together the number proved to be one hundred and seventy myriads: and they numbered them throughout in the following manner:--they gathered together in one place a body of ten thousand men, and packing them together as closely as they could, they drew a circle round outside: and thus having drawn a circle round and having let the ten thousand men go from it, they built a wall of rough stones round the circumference of the circle, rising to the height of a man's navel. Having made this, they caused others to go into the space which had been built round, until they had in this manner numbered them all throughout: and after they had numbered them, they ordered them separately by nations.

Herodotus of Halicarnassus · trans. G. C. Macaulay, 1890
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