or Double-walkers. Those aerial duplicates of men or women who represent them so minutely as to deceive those who know them. We apply the word to such persons as the Dromio brothers, the Corsican brothers, and the brothers Antipholus. The “head centre Stephens” is said to have had a double, who was perpetually leading astray those set to hunt him down.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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