Harry was born on 17 January 1886 in Kettering, Northamptonshire, the third child of Henry and Mary Elizabeth (née Botterill) Coles, with Mary E (1882), Joseph R (1884), Arthur F (1888) and Robert (1901) completing the family unit living in Kettering, Northamptonshire.

Harry joined the Royal Navy on 21 February 1902, 1 month after his 16th birthday when he crossed the gangway of HMS LION (a 3 masted, 2 deck ship of the line 1847-1904) used as a “Boy Training Ship” moored off Torpoint, Devonport and signed on as a Boy Second Class. On 13 November he was advanced to Boy First Class, and, on 11 August 1903, transferred to HMS AGINCOURT (that became BOSCAWEN lll and then GANGES ll ) another “Boy Training Ship” moored in Portland, Dorset, for 1 month before a draft to the battleship HMS ROYAL SOVEREIGN on 15 September 1903.  On 7 October 1903 he was drafted to HMS DUNCAN where on board he was advanced to Ordinary Seaman on 12 January 1904.

On 9 September 1905 he was rated up to Able Seaman before being drafted to HMS VERNON on 28 November 1905, HMS VICTORY l on 6 May 1906, HMS HECLA on 10 January 1907 with a return to VERNON on 13 April. He was back in HECLA on 1 May 1907 for 1 year, thence to VICTORY l on 5 May 1908, HMS CRESCENT on 17 May, HMS ORION 1 on 1 June, HMS MERCURY on 25 August 1908. Here he volunteered for service in submarines and so was drafted to HMS BONAVENTURE, the submarine depot ship based in Harwich, on 22 January 1909 to serve on HMS C11.

In the late afternoon of 14 July 1909, HMS BONAVENTURE and 8 submarines of the 6th Submarine Flotilla left Grimsby along with 8 torpedo boats and turned South for the Thames Estuary. At 2345 the flotilla was travelling at 11 knots and was 4.5 nautical miles off the Hasboro Light Vessel. C11 was the lead vessel of the Port column. Heading in the opposite direction was the collier SS EDDYSTONE who had not been informed of the flotilla’s presence in the area. The EDDYSTONE’s course had her crossing ahead of the three columns of warships, submarines and torpedo boats.  The merchant vessel swung away to avoid collision but collided with C11 and her bows tore into the stern of the submarine which disappeared within 35 seconds of the impact, trapping 13 crew members inside  the sinking vessel. Only 3 of the 16 man crew survived.

Able Seaman Harry COLES,  aged 23,  Svc No. 219513,  had “Crossed The Bar” with 12 of his fellow crew members.