Drew, however, was forced to wait seven minutes by his watch. He chafed at the delay. He crossed his legs at least once each leaden minute. He feared that the trail was getting cold. Twice he rose, as if to go. Each time the secretary had indicated patience by an arching of her brows and a jerk of her thumb toward the ground-glass door. "Send in Drew!" boomed as the door opened and let out the caller. Drew strode in with his notes in his hand. "Just a minute, Westlake," he said, dropping into a chair and leaning over the desk behind which sat a good-natured official of the superior order. "A minute! I'm in a jam! What d'ye make of this?" Drew related his discovery in the booths of the Grand Central. He went right to the point. He explained the auger-hole, the shavings, and the fact that it was the same set of booths to which the call had been sent from the prison, over the time Stockbridge had been slain. Westlake listened with dawning light. He leaned back as Drew finished talking. He smiled. He thrust his thumbs under his vest. "You're a hardworking man, Drew," he said, "but you didn't get it all. Do you remember the third call that I gave you this morning?--the one when the chief-operator at Gramercy Hill put the howler on? It was from the same booths you just mentioned!" "What?" "It certainly was. There's no use looking at the record. The number was 9844 Gramercy Hill. In other words we have the evidence to show that a thin, whispering voice called up Stockbridge from one booth in the Grand Central at the same time the prison was connected to the adjacent booth." "For the love of Mike!" said Drew. "Yes--your case grows interesting, Chief. You've got a lot of tangled leads and all that, but a little more work should untangle them. A telephone engineer ought to make a crackerjack detective. He's trained to unsnarl the worst snarls in the world. You ought to see some of our wiring diagrams. It takes study to trace them out. You're learning!" "I don't know if I am, Westlake. I think that Morphy, up at the prison, has been 'phoning New York. I believe he has a confederate in this town. This confederate, we will say, received his instructions about midnight last night. He bored a hole through the booths and called up Stockbridge. But what was it all for?" "That I can't answer!" Drew rose from the chair and crammed his notes in his inner, overcoat pocket. "What the devil did they do that for?" he asked with flashing eyes. "Morphy calls up Gramercy Hill 9843 at, or about, midnight. Gramercy Hill 9844 calls up Stockbridge. Stockbridge was killed by a bullet in the neck as he's talking over the 'phone. Was the call to warn him? Was it to threaten him? Was it to occupy his attention so that the murderer could get in the room and fire the shot?" "Did you find out how he got into the room?" asked Westlake, leaning forward. "I have not! The whole thing gets weird. I can't sleep! I'm not going to sleep till I get some light on this!"