John Albert Bentinck (29 December 1737 – 23 September 1775) was an officer of the Royal Navy, an inventor and a Member of Parliament. Family background He was a member of the younger line of the house of Bentinck. His father, William, Count Bentinck, was a younger son of the 1st Earl of Portland, and married Charlotte Sophie, daughter of Anton II, the last Count of Aldenburg. John Albert Bentinck was the second son of this marriage. Naval career He entered the Royal Navy at an early age. In August 1752, he was serving as a volunteer on board , in which vessel he visited Lisbon, but returned in the same year to Leyden, where he remained for some time. In 1753, he was appointed midshipman to , a fifth-rate of 44 guns, commanded by Captain Hugh Bonfoy, and joined his ship at Plymouth in June of that year to make a voyage in the following July to Newfoundland. In 1758, Bentinck was present at an engagement in which the British captured the . In the same month, he was appointed to the command of the sloop , and in that vessel took part later in the expedition under Lord Anson to cover the landing of the Duke of Marlborough at St Malo during the Raid on St Malo. He was then for some time stationed with his sloop off Emden, at the time of the capture of Emden, and while there he became involved in an unfortunate misunderstanding, in the course of which he took the extreme step of placing a Captain Angell, his superior officer, under arrest. The affair, however, was cleared up, the accusations against Captain Angell which had prompted his arrest were fully withdrawn, and on 17 October 1758, Bentinck was promoted to be captain of the frigate . In January 1759, being then still on board the Fly, he had to aid in the transport of troops to England, and in March of that year, took up his new command. He did not remain long on the Dover, but was soon removed into the frigate . In this vessel he was employed in 1760 as a cruiser, and distinguished himself highly in an engagement with a French ship of war of very superior weight and armament—the 74-gun Diadème. About a week after this action, in returning from Plymouth, where he had gone to repair damages,