The extreme radius of Zeppelin activity is usually considered to be 600 miles out, 600 miles home, and judged from the three principal Zeppelin centers--Heligoland, Brussels and Friedrichshaven--embraces, with the possible exception of a small and unimportant portion of the west coast of Ireland and north coast of Scotland, every city, military camp, munition factory, dockyard and industrial center in Great Britain. CHAPTER XXIV LAWS OF THE AIR At a recent coroner’s inquest on the death of a young Service pilot in England, an instructor of the flying school at which he was being trained, stated in the course of his evidence that if the pilots--there had been a horrifying collision in mid-air--had only been familiar with aerial rules and regulations, the accident would never have occurred. In this particular instance one machine had been coming down, while another was just leaving the ground. Both of the pilots were aware of the danger they were in, but neither knew the right course to pursue. Result--collision and death. Had both of them carried out the Royal Aero Club’s regulation: that an aeroplane passing another aeroplane in mid-air must leave at least ten meters’ space between the extreme wing-tips and always pass to the right of the approaching craft, both of them would have been alive to-day. So very few of the public outside the flying world are aware that, as navigation of the sea is ordered by the Navigation Act, so is the navigation of the air by the Aerial Navigation Acts of 1911 and 1913, and by the rules and regulations of the Royal Aero Club, which latter organization previous to the war controlled all matters aeronautical and still controls the granting of pilot’s certificates. Even in the ballooning days a charter was drawn up at a conference at Brussels, which ordained that every private balloon--that is to say, one not in the hands of the naval or military authorities--must be registered and have a name and number, which should be printed in large letters on the body of the balloon. The place of residence of the owner must also be stated, and the number and the place of origin be printed in red. Every ascent by a private person must be under the control of a state official. Government balloons, on the other hand, are not expected to carry papers, but private balloons must have a copy of the official particulars and a list of the passengers. A balloon must be identified in the same way as a ship, and must carry a flag, fastened to the net half-way down the balloon, and this must be recognizable both by its shape and coloring, and be properly mounted in position. A journal must be kept and the man in charge must produce his certificate on demand.