We cannot say for certain that this is the right man but among the naval records for August 8 1915 there is a record for a man who looks very likely. His name is recorded as (Henry) John Joseph Mathews and his wife's name as (Edith) Mary. The navy has compiled lists of WW1 casualties who are did not survive the last journey of HMS India.

An armed merchantman, India was on guard duty patrolling the coast of Norway when torpedos were fired at her from a German submarine causing the ship to split in two. There were survivors from this incident and some men were rescued from the sea, taken to Norway and interned for the duration of the war, but John Mathews (the name he used) was on the  drowned list.  The names of many men on this  list are not followed by a military number (though John's has an indication that his number places him in Devon at the time of enlistment) through which John could have been traced but on the list supplied by www.devonhonour.org, On this list, John is described as being a private who drowned. At the time of his death, John was fulfilling the function of Chief Steward and no naval rank is given for him.

This John Mathews can be linked to Broadwoodwidger through census returns and to his parents John and Grace Mathews through their address in Broadwoodwidger. We have traced his birth to 1875  and his death to 1915 (aged 40) and are presuming that this was a re-enlistment in which he kept his final rank as given on his previous service record. One day we may find documents by which all of this can be proved without doubt.