"Chief," he said, "that's been done. We've tapped every phone that Weimar's likely to use in the neighborhood of his house and every time he talks from a public station one of our men cuts in from near-by--by an arrangement with Central--and gets every word. But that bird is too wary to be caught with chaff of that kind. He's evidently worked out a verbal code of some kind that changes every day. He tells the man at the other end, for example, to be at the drug store on the corner of Seventy-third and Broadway at three o'clock to-morrow afternoon and wait for a phone call in the name of Williams. Our man is always at the place at the appointed hour, but no call ever arrives. 'Seventy-third and Broadway' very evidently means some other address, but it's useless to try and guess which one. You'd have to have a man at every pay station in town to follow that lead." "How about overhearing his directions to the men he meets in the open?" "Not a chance in the world. His rendezvous are always public places--the Pennsylvania or Grand Central Station, a movie theater, a hotel lobby, or the like. There he can put his back against the wall and make sure that no one is listening in. He's on to all the tricks of the trade and it will take a mighty clever man--or a bunch of them--to nail him." "H-m-m!" mused the chief. "Well, at that, I believe I've got the man." "Anyone I know?" "Yes, I think you do--Morton Maxwell. Remember him? Worked on the Castleman diamond case here a couple of years ago for the customs people and was also responsible for uncovering the men behind the sugar-tax fraud. He isn't in the Service, but he's working for the Department of Justice, and I'm certain they'll turn him loose on this if I ask them to. Maxwell can get to the bottom of Weimar's business, if anyone can. Let me talk to Washington--" And within an hour after the chief had hung up the receiver Morton Maxwell, better known as "Mort," was headed toward New York with instructions to report at Secret Service headquarters in that city. Once there, the chief and Kenney went over the whole affair with him. Cottrell and Gary and the other men who had been engaged in shadowing the elusive Weimar were called in to tell their part of the story, and every card was laid upon the table. When the conference concluded, sometime after midnight, the chief turned to Maxwell and inquired: "Well, what's your idea about it?" For a full minute Mort smoked on in silence and gazed off into space. Men who had just met him were apt to think this a pose, a play to the grand stand--but those who knew him best realized that Maxwell's alert mind was working fastest in such moments and that he much preferred not to make any decision until he had turned things over in his head.