A Brig is a sailing ship, larger than a Sloop of War, but smaller than a frigate, with two masts. The foremast is square-rigged, whilst the mainmast is square-rigged, but also carries a gaff-rigged fore and aft sail known as the spanker or boom sail to make it more manoeuvrable. On the foremast, a brig can fly a triangular trysail, and a staysail from the forestay.
Brigs can be up to 480 tons, 23 to 50 meters (75 to 165 feet) in length, and can carry from ten to eighteen guns.
See also Brigantine.
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