On 26 December 1799, at 10:15 a.m. HMS Viper, under the command Lieutenant John Pengelley and armed with twelve 4-pounder guns and eight ½-pounder swivel guns, was seven or eight leagues south of the Dodman serving as escort to a convoy of three merchant vessels, a sloop, a brig, and a three-masted ship, when she sighted a suspicious vessel sailing towards her. Realising that the approaching vessel was an enemy, Pengelley sailed towards him. The French captain thought that Viper was maneuvering with such timidity that he could prevail. The engagement commenced at 10:45 a.m. The close action continued for three-quarters of an hour, when casualties on board the privateer caused the majority of the crew of the privateer to panic, forcing the captain of the enemy vessel to take flight. A running fight of an hour and a half ensued as Viper pursued her opponent. Eventually, Viper got close enough to be able to pour two broadsides into her enemy, who then struck his colours.

The enemy turned out to be the French privateer Furet, of fourteen 4-pounder guns and 57 men under the command of Citizen Louis Bouvet. Furet was two days out of Saint Malo and had earlier that day put a seven-man prize crew aboard a vessel that she had taken. In the battle with Viper, Furet had four men killed and her first and second captains and six men wounded, four dangerously; Viper had one man wounded, with Pengelley also being slightly injured. Because both captor and captive were much damaged in their sails and rigging, Pengelley put into Falmouth, from where he intended to sail to Plymouth as soon as he could. The French wounded were transferred to the hospital of Mill Prison. Some weeks later the British paroled Bouvet and sent him in the cartel John to Morlaix.

This was a sufficiently notable single-ship action that in 1847, the Admiralty awarded the Naval General Service Medal with clasp "Viper 26 Decr. 1799" to the one surviving claimant from the action.