“You may argue—but I have too much respect for your judgment, Watson, to think that you will do so—that the ring may have been taken before the man was killed. The fact that the candle had been lit only a short time shows that there had been no lengthy interview. Was Douglas, from what we hear of his fearless character, a man who would be likely to give up his wedding ring at such short notice, or could we conceive of his giving it up at all? No, no, Watson, the assassin was alone with the dead man for some time with the lamp lit. Of that I have no doubt at all.
“But the gunshot was apparently the cause of death. Therefore the shot must have been fired some time earlier than we are told. But there could be no mistake about such a matter as that. We are in the presence, therefore, of a deliberate conspiracy upon the part of the two people who heard the gunshot—of the man Barker and of the woman Douglas. When on the top of this I am able to show that the blood mark on the windowsill was deliberately placed there by Barker, in order to give a false clue to the police, you will admit that the case grows dark against him.
“Now we have to ask ourselves at what hour the murder actually did occur. Up to half-past ten the servants were moving about the house; so it was certainly not before that time. At a quarter to eleven they had all gone to their rooms with the exception of Ames, who was in the pantry. I have been trying some experiments after you left us this afternoon, and I find that no noise which MacDonald can make in the study can penetrate to me in the pantry when the doors are all shut.