His docility still surprised me.

Thanks to hasty pencil-notes, he was able to reproduce, almost textually, the questions and the answers given.
It looked as if Monsieur Darzac were being employed as the secretary of my young friend and acted as if he could refuse him nothing; nay, more, as if under a compulsion to do so.
The fact of the closed window struck the reporter as it had struck the magistrate.

Rouletabille asked Darzac to repeat once more Mademoiselle Stangerson's account of how she and her father had spent their time on the day of the tragedy, as she had stated it to the magistrate.

The circumstance of the dinner in the laboratory seemed to interest him in the highest degree; and he had it repeated to him three times.

He also wanted to be sure that the forest-keeper knew that the professor and his daughter were going to dine in the laboratory, and how he had come to know it.
When Monsieur Darzac had finished, I said: "The examination has not advanced the problem much." "It has put it back," said Monsieur Darzac.
"It has thrown light upon it," said Rouletabille, thoughtfully..