A pistol grip moved under Culver's reaching hand and the strange weapon sprang from concealment like something alive. The pistol grip moved sideways, and the gun swung out and down, its muzzle almost touching the ground. Smithy was suddenly aware that a crystal above his instrument board was reflecting that same bit of sun-baked earth. A dot of black hung stationary at the crystal's center. "That's your target." Culver's voice held all the pride of a child with a new toy, but he released the grip, and the ungainly gun swung smoothly back to its hiding place. He settled himself in the forward cockpit. "You will find a helmet there," he said. "It's phone-equipped; you can tell me all about that wild nightmare of yours while we jog along." The white beam from the despatcher's tower had been on them while they talked. Other planes were waiting on the field. Smithy smiled as he settled the helmet over his head. "For a strictly unofficial flight," he thought, "we're getting darned good service." He taxied past a hangar where uniformed men pointedly paid them no attention. He swung the ship to the line as Airboard regulations required. "N-73" was painted on the monoplane's low wings that seemed scraping the ground. "N-73 Clear!" the despatcher's voice radioed into Smithy's ears. Then the seven-hundred-and-fifty-horsepower DeGrosse let loose its voice as Smithy gunned her down the field. * * * * * Whatever doubts Colonel Culver may have had of Smithy's ability were dissipated as they made their way cautiously through the free-flying area under five thousand. Everywhere were mail planes, express and passenger ships taking off for the transcontinental day run, and private planes scattering to the smaller landing areas among the flashing lights of the flat-topped business blocks. Among them Smithy threaded his way toward the green-lighted transfer zone, where he spiraled upward. At ten thousand he was on his course. He set the gyro-control which would fly the ship more surely than any human hands, and the air-speed indicator crept up to the four hundred and fifty miles an hour that Culver had promised. Not till then did he give the man in the forward cockpit the details of his "nightmare." He had not finished answering the other's incredulous questions when he throttled down to slow cruising speed and nosed the ship toward a distant expanse of sage-blurred sand. Outside the restricted metropolitan area he had already dropped out of the chill wind that struck them at ten thousand. Behind them and off to the right was the gray rampart of the Sierra. Ahead a rough circle of darker hills enclosed the great bowl he had learned to know as Tonah Basin. * * * * *