"Yes, but on this side there is the wall, and if you succeed in
climbing it, how are you going to get over it again with Thomas Roch?
What if the madman cries out--what if he should resist--what if his
keeper gives the alarm?"

"Don't worry yourself in the least about that. We have only got to go
in and come out by this door."

Captain Spade pointed to a narrow door let into the wall a few
paces distant, and which was doubtless used by the staff of the
establishment when they had occasion to go out by the river.

"That is the way I propose to go in. It's much easier than scaling the
wall with a ladder."

"But the door is closed."

"It will open."

"Has it no bolts?"

"Yes, but I shot them back while we were strolling about, and the
director didn't notice what I had done."

"How are you going to open it?" queried the Count, going to the door.

"Here is the key," replied Spade, producing it.

He had withdrawn it from the lock, where it happened to be, when he