In some rural districts the custom still prevails of “Thomasing” - that is, of collecting small sums of money or obtaining drink from the employers of labour on the 21st of December - “St. Thomas's Day.” December 21st is still noted in London as that day when every one of the Common Council has to be either elected or re-elected, and the electors are wholly without restriction except as to age and sex. The aldermen and their officers are not elected on St. Thomas's Day.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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