had no technical training as an engineer, his wide practical knowledge, his courage, and his exuberant vitality made him a man of mark, and engaged the admiration of the public. Most of his work was official; he was killed by the breaking of his machine in the air while flying over Laffan's Plain, in August 1913. Another early inventor, Lieutenant J. W. Dunne, joined the balloon factory in 1906, and at once began to carry out systematic trials with gliders. Encouraged by Colonel J. E. Capper, who was in charge of the factory, and assisted by Sir Hiram Maxim, he devised a biplane glider with a box-kite tail, which when it was suspended from a kind of revolving gallows at the Crystal Palace attained a speed in the air of seventy miles an hour and rose to a height of seventy feet. Later on the experiments were transferred to Blair Atholl in Perthshire, where the power-driven Dunne aeroplane was produced and flown. It had backward sloping wings which performed the function of a stabilizing tail. Most aeroplanes are modelled more or less closely on flying animals; the Dunne aeroplane took hints from the zannonia leaf, which, being weighted in front by the seed-pod, and curved back on either side, becomes, as the tips of the leaf wither and curl, a perfectly stable aerofoil for conveying the seed to a distance. The gliding powers of the zannonia leaf were first noticed by Ahlborn of Berlin, and several foreign aeroplanes were modelled on it. The stability of the Dunne machine was surprising, and it performed many good flights before the war, but it sacrificed speed and lifting power to stability, so that its history in the war is a blank. Stability spells safety, and safety is not the first condition insisted on by war. An obstinately stable machine is good for trudging along in the air, but it is not easy to manoeuvre in face of the enemy. The Dunne machine adjusted itself more readily to the gusts and currents of the air than to the demands of the pilot. Skilled war-pilots prefer to handle a machine which is as quick as a squirrel and responds at once to the pressure of a finger on the control. If the aeroplane had been developed wholly in peace, some of the stable machines of the early inventors would have come into their own, and would have had a numerous following.