The H.M.S. Fowey was a British ship with a notable history in the colony of Virginia in the days just before the Revolutionary War. It was also listed as part of Lord Cornwallis's small fleet at Yorktown in 1781, though that could well have been a different Fowey. At Yorktown, it was listed as carrying 24 guns.
Edit: that one might have been the one rated "sloop," as anything with 40 guns (as in the tag) would be considered fifth rate, and there are two ships named Fowey on the 1748 list.