Shells with three fuzeholes. They are projected from mortars ( q.v.), howitzers (q.v.), and guns. They will burn furiously for eight or ten minutes, do not burst like shells, but the flames, rushing from the three holes, set on fire everything within their influence.
“Charlestown ... having been fired by carcass from Copp's Hill, sent up dense columns of smoke.” —Lessing: United States
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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