John was privately educated at Bournemouth; at Bristol University College; and at St Bartholomew's Hospital, London, entering in 1903, he obtained the diplomas of M.R.C.S., L.R.C.P. in 1909 and graduated M.B., B.S.[Lond.] in 1908. For six months after qualifying, John was employed on temporary work as assistant house-surgeon at St George's Hospital, and afterwards acted as a house-physician and house-surgeon to the West London Hospital. He returned to Bournemouth in 1911, where, in addition to practicing privately, he held the posts of Medical Registrar to the Hahnemann Home and Visiting Surgeon to the Dispensaries. In the autumn of 1914 he went with a second batch of volunteer helpers from Bournemouth to the English Section of the French Military Hospital at St Malo. He then joined the R.A.M.C. on 15th July 1916, and served with the Salonika Army, entering the war in Salonika on 12th August, where he was attached to the 10th Devonshire Regiment. John was mentioned in despatches for gallant and distinguished services in the field, and was also decorated with the Distinguished Service Order "For conspicuous gallantry and devotion to duty in evacuating a large number of wounded under the most difficult conditions. He was himself subsequently wounded, and though both his feet were practically blown off he ordered his stretcher-bearers to carry away another wounded man first". John was severely wounded on the 12th February 1917 during an attack on the Bulgar Lines, near Lake Doiran, in Macedonia, and later died from his wounds. His Commanding Officer wrote: “You will have received the paper giving the words in which I recommended him for the D.S.O. But that was merely an incident of the raid in which he was wounded. He was always earning D.S.O.’s during the whole six months in which we were in the front line and in which he had to go about his duties daily under shell fire of one sort or another.” One of the senior officers also wrote: “..... was one of the finest men I have ever met, and by reason of his utter unselfishness made everyone in the regiment love him, in spite of the comparatively short time that he was with us. He was always thinking of others before himself...... He was always round doing his job in all weathers, and by his very presence and happy outlook on life cheering and encouraging others to ‘keep going’..... When he was wounded he ordered a stretcher party away to attend to someone else first. Even when they got him into the dressing station, all his thoughts were for the other wounded; he was anxious that they should be attended to before him.” The Director of Medical Services, 12th Army Corps wrote: “He behaved with the greatest gallantry, both throughout his service here and during his illness. He was a shining example to all, and was greatly beloved by the 10th Devons, the regiment he was attached to. If ever thee was a hero, he was one. When he was wounded all his thoughts were for the other wounded, and that they should be carried off the field and attended to first, and his bravery and devotion to duty gained him the decoration of the D.S.O.”. Additionally the Chaplin wrote: “None of us who came into contact with him, men and officers, can ever fully express in words how much his life and work and friendship meant to us. He gave every moment of his life while he was with us working with utter forgetfulness of self and careless of danger to himself for the relief of others’ pain...... One of the officers of his battalion, speaking of him to me said - ‘Hammond was the most perfect Christian I ever knew; he lived his Christianity.’ ” John was the only surviving son of Henry Anthony Hammond and Catherine Charlotte Hammond of Sandridge House, Gervis Road, Bournemouth; and the husband of Julia Mary [daughter of Alexander Craven Ord] Hammond of "Nonington" Talbot Avenue, Bournemouth - married at Bournemouth on 21st January 1909.