"Hello!" he exclaimed involuntarily, and every sense was on the alert in an instant. Two flashes inside the downstairs wing of the house, which Ralph knew Mr. Little used as a library, had glinted across the panes of an uncurtained window. Somebody inside the room had scratched a match which went out, then another which stayed lighted. Its flickerings for a moment illuminated the apartment and revealed two men standing near a desk at one side of the room. "Why," exclaimed the young railroader--"those mysterious men again!" CHAPTER VI IN THE TUNNEL Ralph pressed close to the window pane of Mr. Little's library room but he did not succeed in seeing much. The last match struck revealed to his sight the two men who had acted so suspiciously the day he had seen them hanging around the Overland Express train with Glen Palmer's grandfather. If all that he had surmised and discovered was true, it was quite natural that he should come upon them again. Ralph was less startled than surprised. He wondered what their motive could be in visiting the paymaster's house. "They are not up to burglary," the idea ran through his mind. "It must be they are searching among the paymaster's papers to find out what they can about his system and methods. Yes, that is it." Ralph saw the man who had struck the matches draw from his pocket a tallow candle, evidently intending to light it. His companion had pulled up the sliding top of a desk and was reaching out toward some pigeon holes to inspect their contents. Just then an unexpected climax came. The foot of the young railroader slipped on a patch of frozen grass as he pressed too close to the window. Ralph fell up against this with a slight clatter. The man with the match turned very sharply and suddenly. He glared hard at the source of the commotion. He must have caught sight of Ralph's face before the latter had time to draw back, for he uttered a startled ejaculation. With a bang the desk top fell back in place, the match went out, and the man with the candle fired it wildly at the form at the window with sufficient force to penetrate the pane with a slight crash. Ralph drew back, some fine splinters of glass striking his face. It was totally dark now in the room into which he had peered. He could catch the heavy tramping of feet in flight and a door slammed somewhere in the house. "Hey, there--what are you up to," challenged Ralph, sharply, as he stood in a puzzled way debating what was best to do. He turned about, to face a powerfully-built man, cane in hand, storming down upon him from the front of the house. "It is you, Mr. Little?" inquired Ralph quickly. "Yes, it's me. Who are you? Oh, young Fairbanks," spoke the paymaster, peering closely at Ralph. "Yes, sir." "I thought I heard a pane of glass smash--" "You did. Hurry to the rear, Mr. Little." "What for?" "I'll cover the front." "Why--" "Two men are in your house. They were just at your desk when I discovered them."