Image: Lines drawing of Royal Navy vessel
Plan for Royal Navy 10-gun brig-sloops Zephyr (1823) and Tyrian (1826). HMS Swallow would have been similar in appearance
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Image courtesy of the National Maritime Museum, Greenwich, London, NMM: ZAZ5154, http://collections.rmg.co.uk/collections/objects/84945.html. CC BY-NC-SA 3.0