“I know; that’s why I think it was a sign of revenge. Suppose the motive was revenge and the reason for revenge had something to do with a quarrel in which a small glass or cup figured. That’s the idea, though, of course, it needn’t have been a glass or cup at all, but something with a ring-like edge. Thus, there was a reason for the sign on the dead man’s face.” “I see; though I never could have doped it out like that.” “Oh, I don’t say it’s exactly what happened, but there must have been something of the sort, for what other hypothesis fits the case at all? We can’t imagine Doctor Waring branding his own forehead, and then killing himself, can we?” “No; and if he had, where’s the branding iron—to call it that—and where’s the dagger?” “That’s right. Now, I propose to treat the matter as a murder case, and look for the criminal first, and then find out how he entered the locked room afterward.” “Pooh! those locked rooms—” “You’re ’way off, Morton, when you sneer at a ‘locked room.’” “It was locked—I mean impenetrably locked. There is no secret passage—of that I’m sure. Your ingenious idea of removing and replacing a whole pane of glass was clever, I grant, but we’ve seen that not a pane has been lately reputtied. They’re all framed in old, dried, hard, and even painted putty.” “I know it. But some other such way might have been devised.” “Can’t think of any. We’ve examined all the window sashes and door frame—oh, well, so far as I can see the room was absolutely unenterable. But, notwithstanding, I’m going to work on a murder basis. Because inexplicable as that seems, there are even more insurmountable difficulties in the way of the suicide theory. Now, I suppose you’ve had the finger print expert in?” “No—I haven’t—not yet.” “Good Lord! What kind of a detective are you? Well, get him, and put him to work. What about footprints?” “Inside the room?” “Or outside, either. But inside, I suppose has been trampled by a score of people!” “You can’t get footprints on a thick rug,” the discomfited Morton grumbled. “Sometimes you can. And a polished floor will often show marks. What have you done, anyway?” “There was enough to do, Mr. Cray,” Morton flared back at him. “I have been busy every minute since I began, except for a few hours sleep.” “Over twenty-four hours since the alarm was given. You’ve put in at least twelve, then. What have you done?” “A lot. I’ve found out, to my own satisfaction, that—if it is a murder—Gordon Lockwood knows all about it.” “You suspect him?” “Either of the deed, or of guilty knowledge.” “And his motive?” “Money. That young man is over head and ears in debt.” “To whom?” “To shops—jewelers, florists, restaurants. All the debts a gay young blade would incur.” “You amaze me, Morton. Lockwood isn’t that sort.” “Isn’t he? You’re deceived, like every one else, by that icy calm of his. He stares haughtily, and appears above and beyond ordinary mortals, but he’s deep. That’s what he is, deep.”