She was present at two notable occasions, the surrender of the Dutch fleet in the Vlieter Incident and the capture of Alexandria, and her crew participated in two land attacks on forts.

Wells & Co. of Rotherhithe built Cynthia with a shallow draught and three daggerboards (John Schank's sliding keels) for stability.

[3] Thirteen months later, Cynthia, in company with Diamond, Minerva, Camilla, and the hired armed cutter Grand Falconer captured the American ship Favourite on 19 April 1797.

[4] On 5 October Cynthia was in company with Diamond, Syren and Melampus when they captured the Spanish ship Nostra Senora Del Carmen.

[8] On 28 August 1799, Cynthia was with the British fleet that captured the Dutch hulks Drotchterland and Brooderschap, and the ships Helder, Venus, Minerva, and Hector, in the New Diep, in Holland.

[11] The 32-gun frigate Thames, Captain William Lukin, Cynthia, and some small-craft, attacked the south-west end of Quiberon and silenced the forts.

[11] Because Cynthia was with Pellew's squadron for a time, she benefited from the prize or salvage money for the Vigilant, Menais, Industry, Insolent, Ann and for the wreck of a vessel sold.

[14] She participated in another attack on a fort at the bay of Playa de Dominos (Doniños), outside the port of Ferrol, together with the 74-gun Impétueux, the 28-gun frigate Brilliant, and the 14-gun hired armed cutter St Vincent.

In the morning of 17 August, after the Battle of Alexandria and the subsequent siege, Captain Alexander Cochrane in the 74-gun Ajax, with the sixth-rate Bonne Citoyenne, Cynthia, the brig-sloops Port Mahon and Victorieuse, and three Turkish corvettes, were the first vessels to enter the harbour.

[20] Because Cynthia served in the navy's Egyptian campaign between 8 March 1801 and 2 September, her officers and crew qualified for the clasp "Egypt" to the Naval General Service Medal that the Admiralty authorised in 1850 for all surviving claimants.