Suddenly Ralph was halted. A hand had fallen heavily on his shoulder and he turned swiftly to look at the person who had touched him. It was the tall man in the long black coat who had been sitting in the office of the supervisor. Ralph cried out with satisfaction. “Mr. Adair! I certainly am glad to see you!” “I was looking for you, Ralph. But I supposed you were at home at this hour and I hated to disturb your mother,” said the chief detective of the Great Northern system. “Oh, no. I am around the offices now, every night. Until this Midnight Flyer pulls out, at least.” “I don’t suppose the supervisor knows that, does he?” asked Adair dryly. “He knows it to-night, anyway,” said Ralph, grimly. “I was just asking him for you—or if he knew where you were.” “Indeed? And he said he didn’t know?” “He gave me to understand that he was not giving out information to underlings,” and Ralph laughed shortly. “Oh, well! let that pass. I had something to show you, and here it is.” He hauled out the strange message that he believed had come from Zeph Dallas. Mr. Adair read it swiftly. “That’s just the thing I wanted to know!” he exclaimed. “Hang that Hopkins, anyway! He takes himself as altogether too important. Why, Malone is the man I am after!” “You don’t really think that poor, half-witted fellow can be of real importance in any conspiracy against the road?” asked Ralph, wonderingly. “He has got wit enough to give evidence in court. And he is the sort to turn state’s evidence if he is cornered. The use of such fellows as Malone by men of the calibre of McCarrey is our main chance in bringing the latter to book. “McCarrey has to engage Whitey Malone and others like him to do his dirty work. He has some plan against the division that Malone is to help put through. If the latter is down there at Shadow Valley, as Zeph intimates, I am going to make that neighborhood the main point of my investigation.” “But the strikers are here in Rockton!” cried Ralph. “Foolish as these shopmen and the other strikers are, I would not accuse any of them of being angry enough to commit an overt act against the road. Especially of the nature of train wrecking.” “I should hope not!” gasped Ralph. “Yet we have received written threats to that effect,” said Adair gloomily. “This very train,” and he nodded toward the long line of Pullmans standing beside the platform waiting for the locomotive to back down, “is on the list of those that somebody has threatened to stop.” “The Midnight Flyer?” “Yes. Here comes the old mill. Wait. By Marks is not the fellow for this job, Ralph,” and the detective shook his head. “He’s all right!” exclaimed the young train dispatcher hastily. He was determined to commend the aged engineer after this, not criticize him. “I know that nobody could take that express through to Hammerfest much better than he does. And I am the fellow who makes the schedule.”