This is the kind of flying machine that inventors at the present moment are trying to produce. They have, in their machines, to reproduce artificially two essential conditions that cause a kite to fly. They have to provide a substitute for the strength of the wind, and also a substitute for the pull of the string which keeps the kite at the best angle to profit by that strength. The first they achieve by using a suitable engine or motor, and the second by supplying it with what are called “aeroplanes”--large flat surfaces, light but rigid, inclined at a suitable angle to the horizon. By the use of these the power of the engine is employed to best advantage in causing the machine to sail through the sky. The great advantage of the aeroplane over any other mode of flying is thus described by Major Baden-Powell, one of our greatest living authorities on aeronautical matters: “When people realise that in the case of the aeroplane a contrivance like the awning of a small steam launch is capable of supporting the man and the engines, and that in the case of the balloon a mass like a big ship is necessary to lift the same weight, one can readily understand the advantages of the aeroplane, especially when to the drawbacks of the bulky balloon are added the great difficulties inherent in the retention of a large volume of expensive, inflammable, and subtle gas, ever varying in its density.” The most successful inventors of flying machines at the present day are all Americans, though one of them has made his experiments on this side of the Atlantic. They are Sir Hiram Maxim, inventor of the famous gun, and one of the greatest mechanicians living; Professor Langley, Secretary of the Smithsonian Institute, Washington; and the brothers Wright.