At the time the Introduction was written the Air Force was in the throes of the disintegration which followed the armistice. There were criticisms in the press against the conduct of some of the members of the service. Sir Walter was impatient of these criticisms. “Critics who speak of what they have not felt and do not know, have sometimes blamed the air service because, being young, it has not the decorum of age. The Latin poet said that it is decorous to die for one’s country; in that decorum the service is perfectly instructed.” That is the spirit of his book. At first he intended to devote a longish chapter only to the early history of flying, but as he dipped into the subject he found himself committed to something fuller. The first flight in a power-driven heavier-than-air machine was made on December the 17th, 1903. Eleven years later the question of war in the air was beginning to agitate the minds of half the world. The development of air power in those few short years was amazing. The movement had started with extreme sluggishness. The feat of the Wright brothers attracted little attention at first. The world which is often slow to recognize the significance of contemporary events, did not know that a new era in its history had already opened. Certainly the few years immediately following the flight over the Kill Devil sand hills were years of scepticism and witticism. Only a handful of men laboured in whole-hearted enthusiasm for the cause of the air because they had vision and knew what it meant to the future of the world. But recognition forced itself on the nations of the world. Once interest was aroused it spread with amazing swiftness. People felt uneasy. The aeroplane was taken up as a weapon of national defence. The movement was under way and gathering increasing momentum. The progress of the art must have a share in the record of the war in the air, otherwise the story would not be understood. Sir Walter soon saw this. “If the battle of Trafalgar had been fought only some ten short years after the first adventurer trusted himself to the sea on a crazy raft,” he writes, “the ships, rather than the men, would be the heroes of that battle, and Nelson himself would be overshadowed by the _Victory_.”