"Now for it," Jack said, breathing a little faster in his excitement. "Perhaps we had better have the assistance of your lantern as well. I thought that the poster was there. It was there. I'll swear that that is the very spot, just where that picture of the pretty girl taking the pills is. Good heavens, man, the poster has gone! It has been covered up since we were here before by that mustard advertisement. At the hour after midnight the thing has been done. But the right thing must be underneath. See! The poster is wet!"
Jack advanced to tear the poster down, but the inspector pulled him roughly aside.
"Don't touch it," he said hoarsely. "Whatever you do, don't touch it. Wait!"
[CHAPTER V.]
A VANISHED CLUE.
Jack Masefield paused for Inspector Bates to say more. Possibly the officer was possessed of some brilliant idea, but after the first glance at his face it was easy to see that he was as nonplused as Jack himself. It was only the professional caution that spoke; there was no illumination at the back of the policeman's brain.
"I had hoped that perhaps you had discerned something," Masefield said.
"Not quite that, sir," Bates admitted. "So far I am as much in the dark as you are yourself, but my experience is that nothing is to be gained by haste. What I mean is that a thoughtless movement often destroys a clue of the utmost value. I should like to stand here for a moment and consider my position."
Jack drily remarked that there could be no objection to the course proposed by Inspector Bates. It was very late now; there was nothing to be seen, so that the train of thought of the inspector was not likely to be interrupted. He stood facing the great boarded hoarding with its wealth of gaudy pictorial advertisements, but his face did not lighten, and the moody frown was still on his brow.
"Blessed if I can make anything of it," he said in vexed tones. "Here's a man found dead under the most amazing circumstances. There seems to be no motive for the crime; nothing has been removed from the body so far as we know; the man evidently died where he fell. That he was killed I dare say the medical examination will show."