“We must have more talk,” responded the Chief Constable. “As you say—afterwards.”

The Professor rose and picked up his hat and walking-stick.

“I am going to stay at the Mitre here for a day or two,” he said. “So, if you want me, you’ll know where to find me. But while I am here, I should like to see the scene of all this mystery, and if you’re going out there, Sergeant, I’ll go with you, if I may.”

“Great pleasure, sir,” replied Blick.

He took the Professor out and through the streets of Selcaster to the long straight road that led towards Markenmore. As they walked along he detailed to him the whole of his own proceedings, from the finding of the dead man to the affairs of that morning with Mrs. Braxfield.

“Whether the offering of a reward will do any good, I don’t know,” he said in conclusion. “If anybody had seen such a stranger as you indicate it might, but I’m sure I should have heard of that before now.”

“Ah, you’ll have to go back on your trail—you’ll have to go back on your trail!” said the Professor. “The secret lies away back, I’m convinced. All the theories are wrong, so far!—it’s not money—at least not ready money. It’s the Spindler formula—with its vast potentialities. Now, what does this Mrs. Braxfield propose to offer for information?”

“Don’t know—she didn’t say,” answered Blick. “But we soon shall know. Look there!”

A bill-poster’s cart, driven by a man in white linen overalls, passed them, going rapidly in the direction of the village.

“Her solicitor spoke of having these things out at once,” continued Blick. “He’s evidently lost no time—that chap’s going out to post them.”