The Histories · 4.132

Having heard this the Persians took counsel with one another; and the opinion of Dareios was that the Scythians were giving to him both themselves and also earth and water, making his conjecture by this, namely that a mouse is produced in the earth and feeds on the same produce of the earth as man, and a frog in the water, while a bird has great resemblance to a horse; and moreover that in giving the arrows they were delivering up their own might in battle. This was the opinion expressed by Dareios; but the opinion of Gobryas, one of the seven men who killed the Magian, was at variance with it, for he conjectured that the gifts expressed this: "Unless ye become birds and fly up into the heaven, O Persians, or become mice and sink down under the earth, or become frogs and leap into the lakes, ye shall not return back home, but shall be smitten by these arrows."

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