HMS Comet was launched in 1807 as a Thais-class fireship of the Royal Navy. In 1808 the class were re-rated as sloops, and in 1811 they were re-rated as 20-gun sixth rates. Comet participated in one action that resulted in her crew being awarded the Naval General Service Medal, and some other actions and captures. The Navy sold her in 1815. In 1816 she became an East Indiaman, sailing under a license from the British East India Company (EIC). She sailed between the United Kingdom and Ceylon. It was on one of these journeys that she was wrecked on Cole House Point on the River Thames on 9 August 1828. Royal Navy Commander Cuthbert Featherstone Daly commissioned Comet in January 1808 for the Channel. In June 1808 and Comet went to St Andero to assist Spanish loyalists and bring off any British subjects. On 21 June boats from Cossack and Comet landed seamen and Royal Marines who spiked the guns of Fort St Salvador de Ano and Fort Sedra, near the town of St Andero, to prevent them falling into French hands. They also blew up two magazines, during which Captain Daly of Comet and Lieutenant Read of the Marines were injured when one of the magazines blew up. Comet shared with HMS Seine, Cossack, and in the capture on 29 June of Pierre Caesar (or Pierre Cézar). The Royal Navy took Pierre Caesar into service as . On 9 August the , under the command of capitaine de frégate M. Louis Marie Clément, (a Member of the Legion of Honour), sailed with Diligente and Espiègle, to carry supplies from Lorient to Guadeloupe. On 11 August they encountered Comet. The French, under orders to avoid combat, attempted to escape. Diligente out-sailed her two consorts. Comet caught up with the two laggards, with Espiègle ahead. Comet then engaged Sylphe, capturing her near the Île d'Yeu. In the 20-minute engagement, the French suffered seven men killed and five wounded, most severely; the British had no casualties. This action earned Daly his promotion to Post-captain, dated 18 August. In 1847 the Admiralty awarded the Naval General Service Medal to the three surviving claimants from the action. The British took Sylphe into Royal Navy service as HMS Seagull. Captain Richard Henry Muddle replaced Daly in August 1808. He sailed to Newfoundland on 17 April 1809, and again in 1810-1811. She overwintered there in and