HMS Emerald (1795) dispatched a squadron of five ships, including "Emerald" and commanded by Nelson in the 74-gun , to locate a large invasion fleet that had left Toulon. After receiving intelligence on 22 May, Nelson correctly predicted the French fleet's destination and set course for Alexandria where the British captured or destroyed all but two of the French ships at the Battle of the Nile, which occurred between 1–3 August 1798. "Emerald" missed the battle; having previously become separated from the rest of the squadron in a storm on 21 May, she arrived at Aboukir Bay on 12 August. When Nelson left
Mediterranean campaign of 1798 Citoyenne" finally caught up with the fleet, followed on 17 August by "Seahorse" and "Terpsichore". "Mutine" was detached on 13 August with despatches for the Admiralty and on 14 August Nelson sent seven ships with the six seaworthy prizes to the mouth of Aboukir Bay under the command of Saumarez. This convoy sailed for Gibraltar on 15 August and the following day Nelson burnt "Heureux", followed on 18 August by "Mercure" and "Guerrier", none of which were fit for continued service. On 19 August Nelson separated his remaining ships, leading three vessels northwards towards Naples and leaving a blockade squadron