Dimensions, quite New, and sails very fast." The Royal Navy took her into service as HMS Bacchante. In July 1803 Endymion encountered the East Indiaman , which was returning to Britain after having sailed to Bengal and Benkulen. The officer Paget sent aboard the Indiaman proceeded to press 12 seamen. Culland's Groves captain and second officer protested vehemently that this would leave them short-handed, but Paget was acting within the law. The Royal Navy was short of men and was in the habit of stopping homecoming merchant vessels and taking some of their best sailors. Paget's position was that the men he took were "surplus company, and that he was authorized to press men out of homeward-bound ships." In Autumn 1805, Endymion joined the squadron of Rear Admiral Louis off Cadiz, part of Vice Admiral Nelson's fleet, blockading the allied Franco-Spanish force under Admiral Villeneuve. On 2 October, Nelson ordered Louis's five ships of the line with Endymion to Gibraltar for water and provisions; in consequence, Endymion missed the Battle of Trafalgar on 21 October. In 1807 she took part in the Dardanelles Operation, where she was detached to Constantinople with the British ambassador for negotiations with the Ottoman Empire. The mission was a failure and when the squadron sailed back through the Dardanelles, Turkish shore batteries attacked the British, with Endymion suffering three killed and nine wounded. From 1808 on, Endymion served again in home waters, where she took a number of French privateers. Rockall In August 1810, Endymion, in company with , sailed to the then little-known remote islet of Rockall. T. Harvey, her master under Captain Thomas Bladen Capel, plotted its position to , around north-east its true position. John Purdy's Memoir was long accepted for dating the first landing on Rockall as being on this voyage, on 8 July 1810. However, examining Endymions own logs at the Public Record Office, James Fisher (of the 1955 Rockall landing) discovered that the first landing date was actually Sunday 8 September 1811. Captain Sir William Bolton took command sometime in 1810 through to 9 March 1812. One of her lieutenants during the 1810 voyage was one Basil Hall, who was still with the ship when the 1811 landing was made. In July 1811 Endymion was again within sight of Rockall and made soundings of the Rockall Bank. By 8 September she had returned and hove to east north east.