"Look at the ground, all humps and ravines. On the right, on the left, everywhere, there are places in the rock for observations, so to speak, from which one can hear and see everything that takes place inside the boundaries of the estate. D'Estreicher is there."
"What is he doing?"
"He's searching and, what's more, he is keeping an eye on my investigations. He also—for all that I can't guess exactly the reason—wants the gold medal. And he is afraid that I shall get it before him."
"But we must inform the police!"
"Not yet. This underground hiding-place should have several issues, some of which perhaps run under the river. If we give the ruffian warning, he will escape."
"Then what's your plan?"
"To get him to come out of this lair and trap him."
"How?"
"I'll tell you at the appointed time, and that will not be long. I repeat: the hour draws near."
"What proof have you?"