There was a puzzled note to Mathieson's voice as he answered. "He disagreed with me on the supposed effects of the cosmic rays. It has been my contention that they are of lethal effect, and Gaddon maintained that I was wrong. He kept insisting that they were a source of life energy. That was why we decided to experiment with an animal--to see what effect the rays would have on a living creature ... "But this! I never dreamed of such a possibility--to prove his point he signed his own death warrant!" "That's a story, doctor, a real story!" Trent heard the newsman exclaim excitedly. And then it came to him that the real story was as yet untold. The real story that had been unfolded in his car earlier that day. Fred moved suddenly away from the clamor of the newsmen around the scientist. He knew what he had to do. He hurried across the ground to his waiting coupe outside the Administration building. Then he got behind the wheel and started the motor. He drove to the gate and waited until the guard passed him through, then he turned up the road toward Tucson. As he drove he felt an odd tenseness sweep through him. For he was thinking of what Gaddon had said on the drive up to the Proving Grounds. He was remembering the man's words on the cosmic rays and the secret of eternal life they held. And Fred Trent knew that this was the biggest story. The story that he alone held. It was the big break that he had been waiting for. It would be his exclusive. The inside, personal story of a man who had died to prove his theory. Told as Gaddon himself had related it. With all the vanity of the man, all the pompous assurance he had shown. It would make the headlines and feature sections all over the country. The story of a man who had flown to his death in quest of immortality. And then Trent's thoughts grew sober suddenly. But was he going to his death? Could he be sure that Mathieson was right? That Gaddon was suffering from some streak of insanity that had manifested itself in this final venture of madness? Or could it be that Gaddon might be right, that ... Trent set his lips and sighed. No, that couldn't be true. It was beyond the comprehension of man. What mattered now was the story. The story that would put his name in a thousand papers all over the country. And he thought in that moment of Joan Drake. A warm smile pulled at his lips as he thought of her. This would force her to quit her job now and marry him. The one condition she had made--he had finally overcome. He thought of the date he was supposed to have with her that evening. It would have to be postponed until later. The story came first. And then ... He drove his car swiftly through the outskirts of the city and into the main part of town. Then he pulled up before the offices of the _Tucson Star_ and left his car at the curb. * * * * *