The ship was first commissioned in March 1756 under Captain John Lockhart, and earned a reputation as a fast sailer during service in the English Channel. She made many captures of French ships during the Seven Years War, including 4 in 1756 and 7 the following year. During the peace that followed, the ship sailed to Barbados carrying a timekeeper built by John Harrison, as a part of a series of experiments used to determine longitude at sea. She also served in the American Revolutionary War, capturing the Spanish Santa Margarita of 28 guns off Cape Finisterre on 11 November 1779, and went on to see further service during the French Revolutionary War.