"This failure was wholly my own fault," he said in a low tone. "I knew when I found the duplicate financial statement in Madame Sin's rooms that it was a trap to draw me to Chichester's home. Doctor Satan would never have been so careless as to leave a thing like that behind inadvertently. Knowing it was a trap, I entered it, and found Satan's soulless body. If I'd destroyed it immediately.... But I didn't dream that Madame Sin would follow me so quickly." * * * * * Beatrice's hand touched Keane's fleetingly. He was looking at the geometric figure and did not see the look in her eyes. "The world can thank heaven you're alive," she said softly. "With you dead, Doctor Satan could rule the earth----" There was a knock at the door. Gest was in the hall. "Keane," he said. "I suppose this will sound like a small thing after all you've done. You've saved us from bankruptcy and saved Lord knows how many people from a living death from that time-business you tried to explain to us. Now there's one more thing. Workmen in Chichester's home tell us that they can't build up one of the walls of the library, which is non-existent for some reason. There the room is, with one wall out, and it can't be blocked up! Do you suppose you----" Keane nodded, with a little of his bitterness relieved by a smile. "I remember. The time-diverter was pointed at that wall for an instant as the girl and I struggled. Evidently it was set for maximum acceleration, to burst my heart as it did Wilson's. It got the library wall, which is gone because in the point of the future which it almost instantly reached, there is no library or home or anything else on that spot. I'll bring it back to the present, and to existence again, so you won't have a physical impossibility to try to explain to nervous guests of Blue Bay Resort." "And after that," he added to himself, "I'll destroy this invention of Hell. And I wish its destruction would annihilate its inventor along with it--before he contrives some new and even more terrible toy!"