What happened that night none of us ever knew. Dr. Kent worked late in his laboratory; he was there when Alan and Babs and the housekeeper went to bed. He had written a note to Alan; it was found on his desk in a corner of the laboratory next morning, addressed in care of the family lawyer to be given Alan in the event his father died. It said very little. Described a tiny fragment of gold quartz rock the size of a walnut which would be found under the giant microscope in the laboratory; and told Alan to give it to the American Scientific Society to be guarded and watched very carefully. This note was found, but Dr. Kent had vanished! There had been a midnight marauder. The laboratory was on the lower floor of the house. Through one of its open windows, so the police said, an intruder had entered. There was evidence of a struggle, but it must have been short, and neither Babs, Alan, the housekeeper nor any of the neighbors heard anything amiss. And the fragment of golden quartz was gone! The police investigation came to nothing. Polter was found in New York. He withstood the police questions. There was nothing except suspicion upon which he could be held, and he was finally released. Immediately, he disappeared. Neither Alan, Babs nor I saw Polter again. Dr. Kent had never been heard from to this day, four years later when I flew to join the twins in Quebec. And now Alan had told me that Polter was up there! We had never ceased to believe that Dr. Kent was alive, and that Polter was the midnight marauder. And as we grew older, we began to search for Polter. It seemed to us that now we were older, if we could once get our hands on him, we could drag from him the truth in which the police had failed. * * * * * The call of a traffic director in mid-Vermont brought me back from these vivid thoughts. My buzzer was clanging; a peremptory halting-signal day-beam came darting up at me from below. It caught me and clung: I shouted down at it. "What's the matter?" I gave my name and number and all the details in a breath. Above everything I had no wish to be halted now. "What's the matter? I haven't done anything wrong." "The hell you haven't," the director roared. "Come down to three thousand. That lane's barred." I dove obediently and his beam followed me. "Once more like that, young fellow--" But he went busy with somebody else and I didn't hear the end of his threat. I crossed into Maine in mid-afternoon. Twilight was upon me. The sky was solid lead. The landscape all up through here was gray-white with snow in the gathering darkness. I passed the city of Jackman, crossing full over it to take no chances of annoying the border officials; and a few miles further, I dropped to the glaring lights of the International Inspection Field. The formalities were soon finished. I was ready to take-away when Alan rushed at me.