The number of stations to be installed would vary with the amount of definition or precision required.
Continuous development can be made, because each square mile is determined by two frequencies which serve the pilot for identifying his position and the engineer in erecting station. These stations can be put on telegraph poles or on sheds, when ther in cities, on the road or on the farm, and each of these stations, unattended, would transmit the two frequencies assigned to that particular location.
Cost would, of course, be proportional to the miles covered and the amount of "definition" required. This cost per square mile would not be greater by this system than by any other system using beams as flying
Text read from the printed page and cleaned; old type leaves the occasional error.