In 1904, several hundred flights were made, some being circular. All this work was carried on in a secluded spot and unpublished. In December, 1905, the world was startled by the news that the brothers Wright had flown for 24¼ miles in half an hour, at a speed of 38 miles an hour. More than this at the time the brothers would not say, and for three years the world thirsted for the fuller knowledge only revealed in 1908. In the interval some went so far as to distrust the statements of the brothers Wright; but those who, like myself, had had the privilege of correspondence with them from their first experiments felt the fullest confidence that every statement they had made was fact. I have somewhat dwelt on the preliminary experiments of the brothers Wright with their gliding structures as indicating the rapidity of progress attained when sound scientific method is combined with practical experiment. Too often in the past there has been a tendency amongst the workers in science to keep theory and practice apart. They are, however, interdependent. Each has a corrective influence on the other. To the labours of the Wright brothers we certainly owe the advent of the mobile and truly efficient military air scout. It is their efforts that have revolutionised warfare. In the present war we see only the beginnings of what will one day be; but they are none the less truly prophetic. It was the enthusiastic Captain Ferber, who later became a victim to his ardour for aërial achievement, who realised what the brothers Wright had accomplished for military aëronautics. The latter having entered into communications with the French Government respecting the sale of their machines, Captain Ferber was deputed by the French Government to go to America and report on their claims. As the brothers Wright at that time so carefully guarded the secrecy of their details, he was not allowed to see the machine when he arrived, and had to be content with the mere hearsay of certain persons at Ohio, who had witnessed their flights. But he had sufficient faith in the brothers Wright to recommend the French Government to buy their invention. The negotiations, however, fell through at the time, but in 1908 Wilbur Wright came to France to carry on experiments at Le Mans, while his brother, Mr. Orville Wright, went to Fort Myers in America. In Wilbur Wright’s machine at Le Mans, the two superposed slightly concave surfaces were about 12.50 metres long and 2 metres wide. They were separated by a distance of 1.80 metres. At a distance of 3 metres from the main supporting surfaces was the horizontal rudder for controlling the vertical motions; this was composed of two oval superposed planes. At 2.50 metres in front of the main supporting surfaces was the vertical rudder, composed of two vertical planes.