Classification
A sloop-of-war was smaller than a sailing frigate and was (by virtue of having too few guns) outside the rating system. In general, a sloop-of-war would be under the command of a master and commander rather than a post captain, although in day-to-day use at sea the commanding officer of any naval vessels would be addressed as "captain". A ship sloop was generally the equivalent of the smaller corvette of the French Navy (although the French term also covered ships up to 24 guns, which were classed as Post ships within the sixth rate of the British Navy). The name corvette was subsequently also applied to British vessels, but not until the 1830s.
American usage, while similar to British terminology into the beginning of the 19th century, gradually diverged. By about 1825 the United States Navy used "sloop-of-war" to designate a flush-deck ship-rigged warship with all armament on the gundeck; these could be rated as high as 26 guns and thus overlapped "third-class frigates," the equivalent of British post-ships. The Americans also occasionally used the French term corvette.
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