Henry Duncan had a line of sailor ancestors on his mother’s side, so it was appropriate that in due course he joined the Royal Navy.
His elder brother Gavin relates in his memoirs: “In those days the first step was a period of training in the old Britannia. Thither he went and passing out in due course, was posted to one ship after another whose names I forget, until at the outbreak of the 1914 war he was lieutenant in H.M.S. Formidable. This ship was sunk in the Channel on New Year’s Eve 1914 by an enemy torpedo. My brother was the senior officer of the remnant of officers and crew who were saved and had the melancholy task of reporting the event to the Admiralty. I do not know what was in his report but have a vivid recollection of what he and others said of the order which had sent a cruiser squadron into the Channel unescorted by destroyers when enemy submarines were known to be lurking there. There followed a spell in one of those dressed-up tramps [Q-ships] whose aim it was by their innocent appearance to lure enemy submarines to their destruction – an adventure very suitable to his histrionic abilities. Then he was commissioned to the “Warspite” on her first commission and in her took part in the battle of Jutland. It will be recalled how something went wrong with her steering gear and she did an unwilling half-circle under heavy fire from a large part of the German fleet. However she staggered home under her own steam. My brother was uninjured but for long afterwards a chunk of steel severed by an enemy shell from the gun turret which he commanded was kept by him as a memento of a near miss. When the war was over he resigned his commission and joined the brewery where his chief duty was the organisation and supervision of transport. His experience as a naval officer in administration and his knowledge of men made him a valuable member of the board.”
He married Molly Zillah Ramsden in 1927 and the family holidayed in Bembridge, Isle of Wight, where they were keen sailors, still remembered at Bembridge Sailing Club.