"I would have you tied till your bones were locked together. Beat him, you! He is trying to gain time."
"If you beat me," said Wimsey, "I'm damned if I'll speak at all. Control yourself, madame; it does not do to move hastily when your king is in check."
"Get on!' she cried again, stamping with rage.
"Where was I? Ah! the inner compartment. As I say, it is a little snug—the more so that it is not ventilated in any way. Did I mention that the book lay on a steel shelf?"
"You did."
"Yes. The steel shelf is balanced on a very delicate concealed spring. When the weight of the book—a heavy one, as I said—is lifted, the shelf rises almost imperceptibly. In rising it makes an electrical contact. Imagine to yourself, madame; our revered President steps in—propping the false door open behind him—he sees the book—quickly he snatches it up. To make sure that it is the right one, he opens it—he studies the pages. He looks about for the other objects I have mentioned, which bear the marks of finger-prints. And silently, but very, very quickly—you can imagine it, can you not?—the secret panel, released by the rising of the shelf, leaps across like a panther behind him. Rather a trite simile, but apt, don't you think?"
"My God! oh, my God!" Her hand went up as though to tear the choking mask from her face. "You—you devil—devil! What is the word that opens the inner door? Quick! I will have it torn out of you—the word!"
"It is not a hard word to remember, madame—though it has been forgotten before now. Do you recollect, when you were a child, being told the tale of 'Ali Baba and the Forty Thieves'? When I had that door made, my mind reverted, with rather a pretty touch of sentimentality, in my opinion, to the happy hours of my childhood. The words that open the door are—'Open Sesame'."
"Ah! How long can a man live in this devil's trap of yours?"
"Oh," said Wimsey cheerfully, "I should think he might hold out a few hours if he kept cool and didn't use up the available oxygen by shouting and hammering. If we went there at once, I dare say we should find him fairly all right."