The Yarrow, called by the French the herbe aux charpentiers—i.e., carpenter's wort, because it was supposed to heal wounds made by carpenters' tools. Called Achillea from Achilles, who was taught the uses and virtues of plants by Chiron the centaur. The tale is, that when the Greeks invaded Troy, Telephus, a son-in-law of King Priam, attempted to stop their landing; but Bacchus caused him to stumble over a vine, and, when he had fallen, Achilles wounded him with his spear. The young Trojan was told by an oracle that “Achilles (meaning milfoil or yarrow) would cure the wound;” but, instead of seeking the plant, he applied to the Grecian chief, and promised to conduct the host to Troy if he would cure the wound. Achilles consented to do so, scraped some rust from his spear, and from the filings rose the plant milfoil, which, being applied to the wound, had the desired effect.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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