The Histories · 7.32

Having come to Sardis he proceeded first to send heralds to Hellas, to ask for earth and water, and also to give notice beforehand to prepare meals for the king; except that he sent neither to Athens nor Lacedemon to ask for earth, but to all the other States: and the reason why he sent the second time to ask for earth and water was this,--as many as had not given at the former time to Dareios when he sent, these he thought would certainly give now by reason of their fear: this matter it was about which he desired to have certain knowledge, and he sent accordingly.

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