Apart from the factory, or factories, upon a modern aerodrome, there are the offices of the company which controls it; and in addition the sheds of various firms which, renting accommodation from the owners of the ground, are operating flying schools or experimenting with new machines. So that a day spent at an aerodrome, and particularly at such grounds as Hendon or Brooklands, is never for a moment dull. Even when there is no air-racing, a fund of interest may be found in the doings at the sheds; while on those days when a programme of contests is carried out, and racing craft are “banking” round the pylons, there is so much to be seen that a spectator becomes almost bewildered. Air-racing, as made popular by the proprietors of the Hendon aerodrome, forms so fascinating a sight that, on a day of public holiday, as many as 50,000 people will assemble in the enclosures. To stand near one of the pylons--wooden towers which mark the turning-points of the course--and see the air-racers come rushing by, is to gain such an impression of speed as almost makes the watcher hold his breath. The pilot in a flying race has one chief aim: to fly the shortest way. Every fraction of a second is of importance; and if he can circle the pylons more skilfully than his rivals, he may win the race, even though his machine--in its actual speed--may be no faster than theirs. So a flying race, from the moment the timekeeper waves his flag and the machines leap from the starting line, is a contest of sheer nerve and skill. To fly a winning course, upon a high-powered craft, requires, indeed, a judgment that is exceptional. Towards each of the mark-towers, hurtling through the air at perhaps 100 miles an hour or more, comes the airman with a roar and rush. Peering above his screen, in the fierce wind-blast, he seeks to gauge distance and speed; and here, if ever there was one, is a crucial test of airmanship. The pilot knows that, if he would hope to win the race, he must pass as close to each tower as his skill can take him; and yet, even while he strains to this end both nerve and eye, he must not forget for an instant what is the penalty for error. Were he to press too hard upon the rudder-bar, were the wing-tip to strike the tower instead of sweeping past it, his machine would swerve sideways with the momentum of its rush, and break itself to fragments as it crashed upon the ground.