|15 August 1792– 21 April 1862 (aged 69)|
|Place of birth||Edinburgh, Scotland|
|Place of death||Bath, Somerset, England|
|Years of service||1805-1862|
|Relations||Captain George Duff RN
The son of Captain George Duff RN, and Sophia Dirom, he was born at 9 South Castle Street, Edinburgh. He entered the Royal Navy in July 1805, just before his 13th birthday, serving aboard his father's ship HMS Mars as a midshipman. In October 1805 at the Battle of Trafalgar his father was killed.
Duff was promoted to Lieutenant in September 1811 and was appointed Flag-Lieutenant to the commander-in-chief in February 1814. He served on HMS Euralyus. He was promoted to Commander on 15 June 1814 and appointed to command of the 18-gun brig-sloop HMS Espoir, part of the naval force in the Chesapeake during the War of 1812, and later took part in the attack on New Orleans.
In October 1816 Duff was appointed to command of the 10-gun brig-sloop HMS Beaver and sent to the Caribbean , where he assumed command of the 18-gun HMS Rifleman in September 1817. He returned to England in August 1818. 
He undertook an extensive continental European tour in 1819 of which he kept a journal. He was promoted to Post captain on 23 April 1822.