In July 1800, Devonshire was given command of His Majesty's Sloop Dart and fought on board at the Battle of Copenhagen on 2 April following, after which he was made an acting captain.
Re-assigned to North America in the 74-gun HMS Albion in February 1813, Devonshire was on blockade duty off Providence, Rhode Island, when, on 5 December, USS President escaped to sea.
Devonshire later transferred to HMS Sceptre serving in the English Channel but was forced to resign his commission due to ill health.
He was forced out of retirement in order to qualify for an additional promotion and in January 1829, he took command of HMS Kent, a guardship on the Hamoaze at Plymouth.
Born in Cornwall in 1774, John Ferris Devonshire joined the Royal Navy in 1788, as a volunteer aboard the guardship, HMS Cumberland, at Plymouth.
[3] In 1794, Devonshire, who had been commanding various small vessels and co-operating with a Spanish brig in curbing piracy in the waters around Puerto Rico, was rewarded for his conduct when John Jervis promoted him to acting ninth lieutenant aboard the flagship, HMS Boyne.
[4] Since the beginning of that year, Boyne and the other ships in Jervis's fleet, had been supporting troops under Charles Grey in the capture of the French Islands of Martinique, St Lucia and Guadeloupe.
[4] Devonshire was responsible for communication between the fort and ships, and the transport of supplies; a role he maintained until the troops were evacuated at the end of December.
[19] He and his ship served, in particular, in support of the garrison on the Isla de Leon, until the French were forced to withdraw after their defeat at the Battle of Salamanca in July.
[20] In January 1814, Devonshire was in command of a small squadron, comprising Albion, a frigate and a sloop, which menaced enemy shipping off the Nantucket Shoals and took many prizes.
[21] In order to gain a promotion, Devonshire was obliged to seek a further appointment and in January 1829, he took command of HMS Kent, serving as a guardship on the Hamoaze, Plymouth.
[22] Devonshire retired a rear-admiral on 22 July 1830,[22] he was nominated a Knights Commander of the Royal Guelphic Order in January 1835,[23] and died early in 1839.