The Royal Naval Air Service has lost a valuable officer by the death in a flying accident of Squadron-Commander Dalrymple Clarke. Before joining the R.N.A.S., in 1913, he was in business in London, and prior to that he was an officer of cavalry. After joining the R.N.A.S., he was stationed for some time at Eastchurch, and quickly showed that he was not only a very fine pilot, but had the gift of studying his machine’s peculiarities and reporting thereon in a manner which made his tests of high value to the Service. From Eastchurch he was transferred to the Central Flying School, under Commodore (then Captain) Godfrey Paine, R.N., and was appointed an instructor. There he did much useful work, and was responsible for the training of many pilots who have since distinguished themselves on active service. Later on he was appointed to experimental work, and carried out many tests which produced far-reaching results, not only as regards aeroplanes, but also concerning engines, bomb-dropping, and various scientific adjuncts to aircraft. Another loss to the Royal Naval Air Service and the country came with the death of Flight-Lieutenant Charles Walter Graham, R.N., D.S.O., who was awarded the D.S.O. for his services on December 14, 1915, when, with Flight-Sub-Lieutenant A. S. Ince as observer and gunner, he attacked and destroyed a German seaplane off the Belgian coast. The Royal Flying Corps lost another most promising officer with the death in action of Captain J. O. Cooper, R.F.C., previously reported missing, now stated to have fallen in action. He was twenty years of age, and was the youngest son of Lady Cooper, of Ossemsley Manor, Christchurch, Hampshire. Educated at Lockers Park and Harrow, he returned from Australia for the war. He joined the R.F.C. and got his commission in January, 1915. Captain Cooper was considered by all who knew him one of the most promising men in the R.F.C., and if he had been spared would, it is said, have led a squadron before he was twenty-one.