The Histories · 8.28

Thus had the Phokians done to the Thessalian footmen, when they were besieged by them; and they had done irreparable hurt to their cavalry also, when this had invaded their land: for in the pass which is by Hyampolis they had dug a great trench and laid down in it empty wine-jars; and then having carried earth and laid it on the top and made it like the rest of the ground, they waited for the Thessalians to invade their land. These supposing that they would make short work with the Phokians, riding in full course fell upon the wine-jars; and there the legs of their horses were utterly crippled.

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