Action of 4 August 1800 The Action of 4 August 1800 was a highly unusual naval engagement that took place off the Brazilian coast during the French Revolutionary Wars . A French frigate force that had been raiding British commerce off West Africa approached and attempted to attack a large convoy of valuable East Indiamen , large and heavily armed merchant vessels sailing from Britain to British India and China . The East Indiamen were escorted by the small British ship of the line HMS " Belliqueux " , but otherwise had to rely on their individual armament of 30 cannon to protect them from attack . Due to their large size , the East Indiamen could be mistaken for ships of the line at a distance , and the French commander Commodore Jean - François Landolphe was un - nerved when the convoy formed a line of battle . Assuming his target to be a fleet of powerful warships he turned to escape and the British commander , Captain Rowley Bulteel immediately ordered a pursuit . To preserve the impression of warships he also ordered four of his most powerful East Indiamen to join the chase . The larger British ship " Belliqueux " rapidly out ran Landolphe ' s flagship " Concorde " , leaving Landolphe with no option but to surrender without any serious resistance . The rest of the French squadron continued to flee separately during the night , each pursued by two East Indiamen . After an hour and a half of pursuit , with darkness falling , the East Indiaman " Exeter " came alongside the French " Médée " , giving the impression by use of lights that she was a large ship of the line . Believing himself outgunned , Captain Jean - Daniel Coudin surrendered , only discovering his assailant ' s true identity when he came aboard . Horrified , he demanded to be allowed to return to his ship to continue the fight , but Captain Henry Meriton on " Exeter " refused . The action is the only occasion during the war in which a British merchant vessel captured a large French warship . Background . By 1800 , the British and French had been at war for seven years and the British dominated the sea , following a number of significant victories over the French , Dutch and Spanish fleets . Off every French port , large squadrons of British ships of the line and frigate s awaited French movements and whenever possible intercepted and destroyed French merchant vessels and warships . While British trading ships travelled in large , well - armed convoys , French ships were forced to slip between harbours to avoid the British blockade squadrons . To counter the British control of the seas , the French periodically despatched squadrons of ships to raid British trade lanes , particularly off West Africa and in the South Atlantic , where the stretched Royal Navy maintained only minimal forces . The large convoys of East Indiamen were among the principal targets for any French raider . These huge ships , carrying up to , sailed from Britain with general cargo , often including military stores and troops , to India or other ports in the Indian Ocean or the Pacific , including China . There they would sell their cargoes and take on spices , tea , silk and other expensive trade goods before making the return journey to Britain . A round trip could take over a year and an East Indiaman sailing to Britain would routinely carry hundreds of thousands of pounds worth of trade goods : A convoy that sailed from Canton in January 1804 was worth over £8 million . East Indiamen were well - protected , armed with up to 30 guns and generally traveled in large convoys in which the ships could provide one another with mutual protection and have the support of a Royal Navy escort , usually including a ship of the line . On 6 March 1799 , a French squadron had sailed from Rochefort . Consisting of the frigates " Concorde " under Commodore Jean - François Landolphe , " Médée " under Captain Jean - Daniel Coudin and " Franchise " under Captain Pierre Jurien it was a powerful force , capable of inflicting significant damage on lightly defended merchant shipping . Eluding the blockade force off Rochefort , the squadron sailed southwards until it reached the coast of West Africa . There Landolphe ' s ships began an extended commerce raiding operation , inflicting severe damage on the West African trade during the rest of the year . Eventually the strain of serving in tropical waters told on the ships and all three were forced to undergo an extensive refit in the nearest available allied shipyards , which were located in the Spanish - held River Plate in South America . Repairs continued for six months , until Landolphe considered the squadron once again ready to sail in the early summer of 1800 . The squadron almost immediately captured an American schooner , which it fitted out as a tender . At the time , France and the United States had been engaged for two years in the Quasi War . Battle . At 07 : 00 on 4 August , Landolphe ' s lookouts sighted sails on the horizon while cruising off the Brazilian coast . Uncertain of the identity of the strange ships , the French squadron gradually closed the distance during the morning : Landolphe could see that there were seven large vessels and three smaller ships , all unmistakably British . He was unable however to tell whether they were naval ships of the line or mercantile East Indiamen . Initially he thought they might be merchant ships , but at noon he sighted double rows of gunports along the side of each ship and called off the attack , turning away and signalling for his squadron to split up , assuming the enemy to be large warships capable of destroying his small force with ease . Captain Jurien protested Landolphe ' s order , insisting that the convoy was composed of merchant ships and not warships , but his protests were overruled . In fact , Jurien was correct – only one of the vessels posed a serious threat to his force : the seven ships were a convoy of six large East Indiamen sailing from Britain to India , escorted by the 64 – gun ship of the line HMS " Belliqueux " under Captain Rowley Bulteel . With the French in full flight , Bulteel determined to continue the ruse that his convoy consisted of warships . Ordering " Belliqueux " to pursue " Concorde " , he signalled for his largest East Indiamen to follow the other French ships , to ensure that they did not return and counterattack the convoy while " Belliqueux " was engaged . " Exeter " under Captain Henry Meriton and " Bombay Castle " under Captain John Hamilton were to follow " Médée " while " Coutts " under Captain Robert Torin and " Neptune " under Captain Nathaniel Spens were to follow " Franchise " . All four vessels were over and carried 30 guns , but none had more than 130 crew aboard and could not compete in accuracy or rate of fire with the 315 men aboard each of the French ships . Throughout the afternoon the chase continued , with " Belliqueux " steadily gaining on the French flagship while " Franchise " made rapid progress beyond the range of her pursuers , accompanied by the American schooner . At 17 : 20 , Bulteel was within long range of Landolphe ' s ship , which returned fire when possible . During the exchange of gunfire neither side suffered damage or casualties , but the ship of the line was clearly gaining on the frigate and within ten minutes Landolphe surrendered rather than see his ship destroyed in an unequal combat . By 19 : 00 , " Franchise " had dumped her lifeboats and a large quantity of guns and supplies overboard , lightening the ship enough for it to far outstrip the pursuit . As night fell the French frigate made a full escape from the British force . " Médée " however had not escaped : although " Bombay Castle " was many miles behind , only distantly visible on the horizon , " Exeter " had been able to follow the frigate closely . Henry Meriton was aware of the disparity between the French warship and his own merchant vessel , but believed that as the frigate had made no effort to fight , her commander must believe " Exeter " to be a ship of the line . Enhancing this image in the rapidly approaching darkness , Meriton arranged lights behind every gunport , whether or not it contained a cannon , creating an effect described as " a fearsome , leering jack - o ' - lantern " . As his ship drew level with the French frigate , Meriton hailed to the enemy ' s deck , calling on them to surrender . Intimidated by this large and seemingly powerful enemy , Coudin decided that his only option was to strike his flag and come aboard the British ship to make a formal surrender . Arriving on board , he was astonished to see far fewer and smaller guns than would be normally carried on a warship . Asked by Coudin to whom he had surrendered , Meriton is said to have replied " To a merchantman " . Appalled , Coudin demanded to be allowed to return to his ship and conduct a formal naval battle , but Meriton refused . Aftermath . The engagement on 4 August 1800 had cost neither side a single man killed or wounded , but still inflicted a severe naval defeat on a powerful French frigate force , ending its cruise : " Franchise " , the only French survivor , had lost many guns and much of her supplies to decrease the ship ' s weight and , although Captain Jurien spent another three weeks off the Brazilian coast before returning to France , he did not see another sail . Bulteel ' s convoy continued on its journey to India , pausing at Rio de Janeiro on 12 August to resupply before continuing on to Saint Helena . The captured frigates were valuable prizes but were not bought by the Royal Navy , thus denying their captors a significant amount of prize money : they been brought into port shortly before the Peace of Amiens and thus were deemed surplus to Navy requirements and not commissioned . The ships and the stores and equipment seized from them were sold privately , and the proceeds from the sale were paid in February 1803 , in addition to the head - money , a financial award for each French sailor captured during the engagement . Bulteel and Meriton were commended , and the latter was to fight two more naval battles against the French , serving at the successful defence of the China Fleet at the Battle of Pulo Aura in February 1804 and eventually being badly wounded and captured by a French frigate squadron after a fierce defence at the Action of 3 July 1810 .