Jimmy had been in fog before, but he had never made a trip such as this one promised to be. Always the fogs he had ridden through had dissipated after a time, but this fog-bank bade fair to cover every inch of the four hundred and fifty miles or so to his home field. The possibilities of getting lost, of crashing, of meeting with dire disaster in a flight of such length, were too many for Jimmy to allow himself to consider them. He did not permit himself even to think of these possibilities. Instead, he called up every bit of flying ability he possessed to meet the situation. At two or three hundred feet elevation he had gone blind. From that point onward, he had to fly wholly by his instruments. Setting his course by his compass, he sat listening to the guiding note of the radio beacon, his eyes glued to the instrument board. From his compass his eyes darted to his turn-and-bank indicator, then to his air speed indicator. Occasionally he glanced at his engine instruments, to see that his propeller was making the necessary revolutions per minute, that the engine temperature was not too high, that his oil pressure remained constant. But mostly he kept watch of his speed and of his position. The steel ball in the centre of the turn-and-bank indicator had to be kept right in the centre. Every time the ball began to slide one way or the other, Jimmy had to bring his ship back to a level keel, for the moving steel ball showed that he was beginning to dip to one side or the other. Sense of balance told him little or nothing; and had it not been for his indicator, he might soon have been flying upside down, as many a pilot before him had done. Nor could he allow his ship to drop below a speed of sixty miles an hour, lest it come crashing to earth. All the while the radio beacon signal was buzzing loudly in his ears. “Dah, dah, dah, dah, dah, dah,” the signal sounded. It came to him with startling intensity. That was because his ship was close to the beacon itself. As he traveled onward, Jimmy knew, the signal would grow fainter and fainter, for during the first half of the flight to Bellefonte he would be guided by the signals from the airport he had just left. Beyond that he would be guided by the Bellefonte signals, and he knew these would grow ever louder as he neared that field.