Radio operators will be in great demand for flying. Brig.-Gen. A.C. Critchley, the youngest general officer in the British service, who was a pilot in the Royal Air Force, said that the future development of the airplane must go hand in hand with the development of wireless communication. He added that the most difficult thing about flying, especially ocean flying, was to keep the course in heavy weather. There are no factors which will help a man on "dead" reckoning; and a shift in wind, unknown to the navigator of a plane, will carry him hundreds of miles from his objective. The wireless telephone was used to some extent during the war for communication between the ground and the air; it will be used to a greater extent in the next few years. Another development which is being used by the navigators flying the Atlantic is the radio compass. This instrument may be turned toward a land or sea wireless station, of which the call is known, and it will register the bearing from the flying-boat to this station. It may be turned upon another station, and this bearing also charted. The intersection of these two wireless compass bearings gives the position of the ship at sea. The radio compass is dependable day or night, and is said to be quite as reliable as a sextant or other navigating instruments. Sailmakers to repair airplane fabrics, to sew new covers for planes--these men must find an opportunity in flying. There are literally thousands of wings, as yet unmade, which will carry the air traffic of the future. It matters not whether men or women take up this branch of the work, it must be done, and done with a conscience. Like all other branches of the mechanical maintenance of an airplane, careless work on the part of a sailmaker may mean disaster for the pilot. One of the latest fatalities at a Long Island flying-field was due to careless stitching, or weakness of fabric, which gave way under great pressure due to high speed. The linen cover of an upper plane ripped off at a height of one hundred and fifty feet, and the pilot was killed in the fall of the machine. Photographers may yet take the place of surveyors, or work hand in hand with them in the making of aerial maps of the country. The map of the future must be an aerial map, a mosaic map such as was used by our army headquarters. Nothing can exceed the eye of the camera for accuracy. Cameras bolted to airplanes, such as were used by our army for reconnaissance, have already been used for mapping cities. The mapping of the entire country in such a manner is only a matter of time. One thing which an aviation mechanic of any sort must bear in mind is that he _must_ do his work with a conscience. True, he is handling mute metal engines, or dumb wires and struts--but in his work he holds the life of the pilot in his hand. It is not too much to say that hundreds of pilots' lives have been saved by the conscientious work of skilled mechanics who realized the danger of the air.