One of the features of this machine, was its method of obtaining lateral stability. Farman recognised the disadvantages of the vertical planes, as used in the Voisin machine. So he fitted small flaps, or horizontal planes, at the rear extremities of his mainplanes. These were hinged to the main-planes, and were termed "ailerons." Their operation produced the same result as in the application of the wing-warping device of the Wright brothers. When the biplane tilted sideways in flight, the "ailerons" were drawn down, by means of controlling wires, on the side that was depressed. The air pressure, acting upon the surfaces of the "ailerons," forced the aeroplane back upon an even keel. When not in operation, the "ailerons" flew out straight in the wind, on a level with the main-planes. The control of the Farman biplane was effected by means of a hand and foot lever. The hand lever, when moved forward or backward, operated the elevating plane. When shifted from side to side, it actuated the "ailerons." The pilot’s feet rested upon a pivoted bar, which he swung from side to side to move the rudder of the machine. [Illustration: BRITISH-BUILT SCOUTING MONOPLANE. This aircraft, an exceedingly fast, single-seated machine, represents the type of machine now favoured by French authorities for urgent, rapid, general reconnaissance. Its constructors are Messrs. Short Brothers.] Another constructional feature of this first Farman biplane was notable. This was the landing chassis. Appreciating the disadvantages of the Wright launching rail, and recognising that the Voisin chassis was heavy, Farman aimed at something lighter, and at the same time more efficient. Again he succeeded. He devised a chassis which was a combination of wooden skids and bicycle wheels. Below his biplane, upon wooden uprights, were fitted two long wooden skids. On either side of each skid, were two little pneumatic-tyred bicycle wheels, connected by a short axle. The wheels were held in position on the skid by stout rubber bands, which passed over the axle. Normally, the skids were raised off the ground by the wheels, upon which the biplane actually ran. But, in the case of a rather abrupt descent, the chassis was so designed that the wheels were forced up against their rubber bands, thus allowing the skids of the machine to come into contact with the ground. Then, when the force of the shock had been absorbed, the wheels came into play again. With this biplane, Farman achieved fine flights at Rheims. Apart from its constructional excellence, the biplane was fitted with a motor which was destined to have a remarkable influence upon the development of flying—and upon military aviation in particular. This was the seven-cylinder, revolving "Gnome." To-day, the application of this wonderful engine is practically universal. In August, 1909, it was regarded quite as a freak, and was seen for the first time upon Henry Farman’s biplane.