During these years, Duff saw action thirteen times on both sides of the Atlantic, including at the Great Siege of Gibraltar and culminating in the battle of the Saintes in 1782 when he was serving on HMS Montagu.

With a reputation thus secured and plenty of family interest in his career, Duff had little difficulty progressing, being promoted to commander in 1790 and then Post Captain in 1793, a meteoric rise resulting from the growth of the Navy in the buildup to war during this period.

Following the Peace of Amiens, Duff was given HMS Mars,[3] something of a celebrity ship in the Royal Navy following her capture of the French Hercule in 1799 in which her captain Alexander Hood was killed.

Rapidly moulding the ship with his own brand of Scottish discipline, Duff took her to join the fleet off Cádiz at the beginning of October and instantly became friends with Nelson, despite their vastly different characters.

During this approach, which due to poor wind had been conducted at walking speed, Duff was able to write a final note home to his wife, which he entrusted to his thirteen-year-old son Norwich, who was serving as a midshipman on Mars: Dearest Sophia, I have just time to tell you we are going into Action with the Combined Fleet.

The crew were undismayed however, carrying the headless corpse around the deck and giving three cheers in memory of their captain, before replacing him where he fell and covering him with a Union Flag.

A large marble monument by John Bacon with the inscription "Erected at the Public Expense to the memory of Captain George Duff who was killed the XXIst of Octr MDCCCV.