Henry was born in Crewe (Nantwich) on the 22 November 1897 the eighth child of Arthur and Elizabeth (nee Yarwood) Moss, with three elder brothers and four sisters. His mother had three more male children and one female of whom eleven survived to adulthood. Between leaving school and joining the RN on 19 May 1914 Martin had been employed as an engine fitter but preferred and qualified in boys training to become a telegraphist.

Henry joined the Roya Navy when at 16 years and six months old he climbed the gangway for the first time of the converted cruiser HMS POWERFUL in Devonport dockyard as a “Boy 2c” for basic training. In December POWERFUL had a name change and became HMS IMPREGNABLE though it continued in the role of “Boy Traning Ship” and on 14 January 1915 he was advanced to “Boy 1c” , two moths later on the 20 March selected for “Boy Telegraphist”. On the 9 April 1915 he was drafted to Portsmouth and onto the hulks that made up HMS VERNON for five weeks of branch training before joining the battleship HMS QUEEN MARY on the 14 May 1915 as Boy Tel. though  still with an under training draft orders for 4 months,  Finally on the 21 September 1915 he was drafted as Ordinary Telegraphist to a ships compny billet on the cruiser HMS ROYAL ARTHUR the designated submarine support vessel in Scapa Flow. On the first of June 1916 another advancement to Telegraphist , on the 21 April 1917 a draft to HMS LUCIA for the submarine  C 34 of the 10th Flotilla based in Scapa Flow. On the 16 July 1917  C 34 left the harbour for a patrol area North of the island of Fair Isle, it is reported that about midday on the 17 April she was spotted on the surface and stopped in the water by the German submarine U52.

U 52 was able to manouvre into an attack position and that one torpedo released by  U 52 hit  C34 just aft of the bridge causing a large explosion and C 34 sank very quickly. The German submarine surfaced and found one crew member swimming in the wreckage that they recovered and took back to Germany and he was interred as a POW for the rest of the war.