In many places statute fairs are held, where servants seek to be hired. Carters fasten to their hats a piece of whipcord; shepherds, a lock of wool; grooms, a piece of sponge, etc. When hired they mount a cockade with streamers. Some few days after the statute fair, a second, called a Mop, is held for the benefit of those not already hired. This fair mops or wipes up the refuse of the statute fair, carrying away the dregs of the servants left.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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