d one to
the other, but formed of a solid slab, massive, firm, and strong, and
covered with the sheen of time darkened here and there with patches of
rust. On either side and at the top and bottom the edges of the panel
fitted in a narrow groove which covered them hermetically.

He was a prisoner. In a sudden fit of rage he banged at the metal with
his fists. He remembered that Mlle. Levasseur was in the study. If she
had not yet left the room--and surely she could not have left it when the
thing happened--she would hear the noise. She was bound to hear it. She
would be sure to come back, give the alarm, and rescue him.

He listened. He shouted. No reply. His voice died away against the walls
and ceiling of the box in which he was shut up, and he felt that the
whole house--drawing-rooms, staircases, and passages--remained deaf to
his appeal.

And yet ... and yet ... Mlle. Levasseur--

"What does it mean?" he muttered. "What can it all mean?"

And motionless now and silent, he thought once more of the girl's strange
attitude, of her distraught face, of her haggard eyes. And he also began
to wonder what accident had released the mechanism which had hurled the
formidable iron curtain upon him, craftily and ruthlessly.

CHAPTER SIX

THE MAN WITH THE EBONY WALKING-STICK

A group consisting of Deputy Chief Detective Weber, Chief Inspector
Ancenis, Sergeant Mazeroux, three inspectors, and the Neuilly commissary
of police stood outside the gate of No. 8 Boulevard Richard-Wallace.

Mazeroux was watching the Avenue de Madrid, by which Don Luis would have
to come, and began to wonder what had happened; for half an hour had
passed since they telephoned to each other, and Mazeroux could find no
further pretext for delaying the work.

"It's time to make a move," said Weber. "The housekeeper is making
signals to us from the window: the joker's dressing."

"Why not nab him when he comes out?" objected Mazeroux. "We shall capture
him in a moment."

"And if he cuts off by another outlet which we don't know of?" said the
deputy chief. "You have to be careful with these beggars. No, let's beard
him in his den. It's more certain."

"Still--"

"What's the matter with you, Mazeroux?" asked the deputy chief, taking
him on one side. "Don't you see that our men are getting restive? They're
afraid of this sportsman. There's only one way, which is to set them on
him as if he were a wild beast. Besides, the business must be