ing for the stuff. There's a hundred places in the house where it could be hid; and we might search a month and not find it. Anyway, I'll go out there to-night and tell O'Brien to watch for it. If she's on the lookout she maybe can spot any attempt to use it."
"What astounds me," remarked the Inspector, "is the security felt by the thief. Within an hour of the time Rex Greene is shot the poison disappears from the upper hall. Good Gad! That's cold-bloodedness for you! And nerve, too!"
"There's plenty of cold-bloodedness and nerve in this case," answered Vance. "A relentless determination is back of these murders—and calculation no end. I wouldn't be surprised if the doctor's satchel had been searched a score of times before. Perhaps there's been a patient accumulation of the drugs. This morning's theft may have been the final raid. I see in this whole affair a carefully worked-out plot that's been in preparation perhaps for years. We're dealing with the persistency of an idée fixe, and with the demoniacal logic of insanity. And—what is even more hideous—we're confronted with the perverted imagination of a fantastically romantic mind. We're pitted against a fiery, egocentric, hallucinated optimism. And this type of optimism has tremendous stamina and power. The history of nations has been convulsed by it. Mohammed, Bruno, and Jeanne d'Arc—as well as Torquemada, Agrippina, and Robespierre—all had it. It operates in different degrees, and to different ends; but the spirit of individual revolution is at the bottom of it."
"Hell, Mr. Vance!" Heath was uneasy. "You're
