A penny coined by William Wood, to whom George I. granted letters patent for the purpose. (See Drapiers Letters.)
“Sir Walter's [Scott] real belief in Scotch one-pound notes may be advantageously contrasted with Swift's forced frenzy about Wood's halfpence, more especially as Swift really did understand the defects of Wood's scheme, and Sir Walter was absolutely ignorant of the currency controversy in which he engaged.” —The Times.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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