All these aids are splendid for the professional flier, specially one who covers the same course regularly But how about the amateur who is not an expert radio operator who wishes to fly cross-country? The answer is: Do not attempt to fly unless you are positive you will have good weather all along.
A "block" system of avenues crossing each other, just like the avenues of a planned modern city, can be installed over all the important navigational areas and gradually extended to cover the whole country. Each avenue will be characterized by something distinctive: for example, its wave length or its tone.
The variation of wave length (or ether. signal characteristic) should dually increase, or decrease, step y step, as we pass from one avenue to another. Wave length can be read on the dial of a radio receiver. Reeeivers can be made to tune themselves automatically in the signal predominating on any given place. A flier passing over a -series of such beams or avenues, each having its own wave length which varies step by step, can at all times, without touching his radio, read on his dial the number of his "avenue."
Text read from the printed page and cleaned; old type leaves the occasional error.