Guy Hart was born on 21 July 1883 and joined the Royal Navy Training Ship HMS BRITANNIA at the age of 15.  He served briefly in the battleships HMS DUKE OF WELLINGTON, HMS ROYAL SOVEREIGN and HMS FORMIDABLE.  In 1904, he was promoted Sub Lieutenant and appointed to a destroyer running from Portsmouth followed by the Submarine Depot Ship HMS THAMES ‘additional for Training’ . By April 1905 he was serving in ‘Submarine Holland No. 4 in Command’ He was re-appointed to HMS THAMES as a Lieutenant ‘for Command of Submarines’ and took command of HMS C8.

Guy Hart was killed as the result of the diesel engine back firing into the crank pit. The crank pit had been covered by a wooden cover and, as this was a temporary arrangement, the cover had not been bolted down. The temporary cover was in place following a previous crank pit explosion in which the usual aluminium covers had been damaged.

Guy had been sitting on the temporary covers at the time talking to one of his engineers, and was thrown upward and then fell back into the crank pit. He suffered a fractured skull and compound fractures of both legs. He died of his injuries shortly afterwards.

His father was living in Bangalore, India and his brother was Captain Hart, RGA, of Sand Hills, Letchworth, Surrey. He was buried, with full Military Honours in the Haslar Naval Cemetery, Gosport.