As Old Bob seemed to be in a churlish humor, we left him—that is, Rouletabille and myself did. M. Darzac remained gazing at his spoiled drawing, but thinking, doubtless, of altogether different things.

As we went out of the Round Tower, Rouletabille and I raised our eyes to the sky which was rapidly becoming covered with great, black clouds. The tempest was near at hand. In the meantime, the air seemed to grow more and more stifling.

“I am going to lie down in my room,” I said. “I can’t stand any more of this. Perhaps it may be cooler there with all the windows open.”

Rouletabille followed me into the New Castle. Suddenly, as we reached the first landing of our winding staircase, he stopped me:

“Ah,” he said in a low voice; “she is there!”

“Who?”

“The Lady in Black. Can’t you smell the perfume?”

And he hid himself behind a door, motioning me to continue without waiting for him. I obeyed.

What was my amazement in opening the door of my room to find myself face to face with Mathilde!

She uttered a low cry and disappeared in the shadow, gliding away like a surprised bird. I rushed to the staircase and leaned over the balustrade. She swept down the steps like a ghost. She soon gained the ground floor and I saw below me the face of Rouletabille, who, leaning over the rail of the first landing, looked at her, too.