As I stood there on the track before the engine I had a strange sensation. It was very still; there was a ghostly fog, and somewhere beyond me, as though out of the sky, I heard whispering voices. I strained my ears to listen, standing as one does on tiptoe. But I could not be certain. No word was audible to me nor any decided voice, but now and then there seemed to be a murmuring in the fog, and, what was beyond understanding, it seemed behind the engine in the clouded sky. What human creatures could thus whisper in the sky? Mooney and White returned presently in no very pleasant mood. I think the time taken with the thing made them uneasy. White had the loot sack and we started along across the field, to where we had left the automobile on the road. It was then that I got the explanation of the mysterious voices. There were three hobos riding on the top of the mail car. They had been witnesses of everything that had occurred. They sat there like immense buzzards outlined against the dim light of the sky. Mooney stopped a moment. He seemed to reflect, turning his weapon about in his hand. Then he spoke to the derelicts on the top of the car. “If they pinch you for this job,” he said, “write me a letter.” And he went on. I thought for a moment that he intended to shoot the men, but no such idea was passing through his mind. It had occurred to him that, perhaps, these unfortunate derelicts would be charged with the robbery. And, as it happened, they were in very grave danger. The posse that gathered, seeing them on the top of the car, opened a fusillade. It was very lucky that the idea occurred to Mooney, for, as it happened, these men drew all the suspicion of the officials. Three men had held up the train. They were three men. They were afterwards tried before the District Court of the United States and very nearly convicted. No doubt they often recalled those significant words of Mooney’s. But unfortunately he had left them no address to which their communication could be sent. When we got to the car Mooney again turned his lantern on the clock. He swore softly; then he stood back a moment in reflection. “We’re late,” he said, “I don’t see how we could have taken up so much time on this job; it was the cursed mail.” White did not speak and I remained silent, standing by the little man now motionless in reflection. I suppose it must have been five minutes ticked off by the clock while he stood there. Then suddenly he came to a conclusion. “Give me the spook faces,” he said. He meant the masks under the hats. I handed him my hat, pulling the mask up over my face. He seized White’s, drew off his own, and disappeared in the direction of the track from which we had just come.