And who could say what words had passed between them at that final interview? Perhaps Appleby had goaded him to the breaking point; perhaps Wheeler had stood it, but his wife, descending the stairs and hearing the men talk, had grown desperate at last; or, and Stone knew he thought this most plausible of all, perhaps Maida, in her window-seat, had stood as long as she could the aspersions and tauntings directed at her adored father, and had, with a reckless disregard of consequences, silenced the enemy forever. Of young Allen, Stone had no slightest suspicion. To be sure, his interests were one with the Wheeler family, and moreover, he had hoped for a release from restrictions that would let the Wheelers go into Massachusetts and thereby make possible his home there with Maida. For Maida’s vow that she would never go into the state if her father could not go, too, was, Allen knew, inviolable. All this Stone mulled over, yet had no thought that Allen was the one he was seeking. Also, Curtis Keefe had testified that Allen was with him at the fire, during the time that included the moment of shooting. Strolling out into the gardens, the detective made his way to the great tree, the big sycamore. Here Fibsy joined him, and at Stone’s tacit nod of permission, the boy sat down beside his superior on the bench under the tree. “What’s this about the tree going to Massachusetts?” Fibsy asked, his freckled face earnestly inquiring. “One of old Appleby’s jokes,” Stone returned. “Doubtless made just after a reading of ‘Macbeth.’ You know, or if you don’t, you must read it up for yourself, there’s a scene there that hinges on Birnam Wood going to Dunsinane. I can’t take time to tell you about it, but quite evidently it pleased the old wag to tell Mr. Wheeler that he could go into his native state when this great tree went there.” “Meaning not at all, I s’pose.” “Of course. And any human intervention was not allowed. So though Birnam Wood _was_ brought to Dunsinane, such a trick is not permissible in his case. However, that’s beside the point just now. Have you seen any of the servants?” “Some. But I got nothing. They’re willing enough to talk, but they don’t know anything. They say I’d better tackle the ladies’ maid, a fair Rachel. So I’m going for her. But I bet I won’t strike pay-dirt.” “You may. Skip along, now, for here comes Miss Maida, and she’s probably looking for me.” Fibsy departed, and Maida, looking relieved to find Stone alone, came quickly toward him. “You see, Mr. Stone,” she began, “you must _start_ straight in this thing. And the only start possible is for you to be convinced that I killed Mr. Appleby.” “But you must admit, Miss Wheeler, that I am not _too_ absurd in thinking that though you say you did it, you are saying it to shield some one else—some one who is near and dear to you.” “I know you think that—but it isn’t so. How can I convince you?”