'Me lord,' he went on, 'there's a Judas window in nearly every door, if you just come to think of it. I mean that every door has got a knob. This door has. And, as I've pointed out to several people, what a whackin' big knob it is’
'Suppose you took the knob off that door; what'd you find? You'd find a steel spindle, square in shape, runnin' through a square hole - like a Judas window. At each end of this, a knob is attached by means of a little screw through a hole in each end of the spindle. If you took everything out, you'd End in the door an opening - in this case, as we'll see, an opening that must be nearly half an inch square. If you don't realize just how big a space half an inch can be, or how much you can see when you look through it, we'll try to indicate it in just a minute. That's why I objected to the word "sealed".
'Now, suppose you're goin' to prepare this simple little mechanism in advance. From the outside of the door, you unscrew the knob from the spindle. You notice that there's a very small screw-driver contained in the suitcase that was left at Paddington Station; so I'll just ask the Inspector to do it for us now. Ah! That gives you, in the end of the spindle, a little hole where the screw had been. Through this hole you tie tightly a very heavy length of black thread, with a good length of slack. Then you take your finger and push the spindle through its hole to the other side of the door, the inner side of the door. There's now only one knob - the one inside the door - fastened to the spindle; on the other end is attached your length of thread, and you're paying out the slack. Whenever you want the spindle and knob back up again, you simply pull the thread and up it comes. The weight of the knob inside the door is sufficient to make it hang down dead straight, so you've got no difficulty in gettin' the square spindle back in the square hole; it comes up in a straight line and slides in as soon as the edge of the spindle crosses the edge of the Judas window. As soon as it's back in again, you jerk off your thread; you put the outside knob of the door back on the spindle again; you screw it up again ... It's heart-breakin'ly simple, but the door is now apparently sealed.
'Again suppose you'd prepared the mechanism in advance, with the thread already twined. Somebody is in that room with the door bolted. You start to work your mechanism. The feller inside don't notice anything until he suddenly sees the knob and spindle beginnin' to be lowered a little way into the room. You want him to see it. In fact, you begin to talk to him then through the door. He wonders what the - he wonders what is goin' on. He walks towards the door. He bends down, as anyone will when wantin' to look close at a knob. As he bends forward - a target only three feet away from your eye, where you can't miss -'
'My lord,' cried Sir Walter Storm, 'we are willing to grant all liberties, but we must protest against this argument in -'
'- with your arrow balanced in the opening,' said H.M., 'you fire through the Judas window.'
There was a sort of thunderous pause, while Inspector Mottram stood with the screw-driver in his hand.
'My lord, I've had to say it,' said H.M. apologetically, 'in order to make clear what I'm goin' to show you. Now, that door has been in the possession of the police ever since the night of the murder. Nobody could 'a' tampered with it; it's just as it was ... Inspector, have you unscrewed one knob from that spindle? So. Will you sort of tell my lord and the jury what there seems to be tied to the hole in the spindle?'
'Please speak up,' said Mr Justice Rankin. 'I cannot see from here!'
Inspector Mottram's voice rose, a ghostly kind of effect, in the silence. I am not likely to forget him standing there under the glow of the yellow light, with the oak panelling, and the yellow furniture, and the tiers of people who were now frankly standing up. Even the white wigs and black gowns of counsel had reared up furtively to obscure our view. At the core of all this, as though in a spotlight under the white dome of the Old Bailey, Inspector Mottram stood looking from the screw-driver to the spindle.
'My lord,' he said, 'there appears to be a piece of black thread tied to the hole in the spindle, and then wound a few lengths round -'
The judge made a note in his careful handwriting.
'I see. Proceed, Sir Henry.'
'And next, Inspector,' pursued H.M., 'just push the spindle through with your finger - use the point of the screw-driver if it's more convenient - and take the whole thing out. Ah, that's got it We want to see the Judas window, and ... ah, you've found somethin', haven't you? There's somethin' lodged in the opening between the spindle and the Judas window, stuck there? Quick, what is it?'
Inspector Mottram straightened up from inspecting something, in the palm of his hand.
'It would appear,' he said carefully, 'to be a small piece of blue-coloured feather, about a quarter of an inch, triangular in shape, evidently torn off something -'
Every board in the hardwood floor, every bench, every chair seemed to have its own separate creaking. At my side Evelyn suddenly sat down again, expelling her breath.
'And that, my lord,' said H.M. quite mildly, 'together with the identification of the last piece of feather, will conclude the evidence for the defence. Bah!'
XVIII
'The Verdict of You All
4.15 p.m.-4.32 p.m. From the Closing Speech for the Defence, by Sir Henry Merrivale
'... and so, in what I've just spoken to you about, I've tried to outline what we'll call the outlying phases of this case. You have been told, and I think you believe, that this man was the victim of a deliberate frame-up. You have heard now that, far from taking a pistol to that house, he was goin' to see the one man in the world he wanted most to please. You have heard the details that twisted up everything he said to an extent that will make me, for one, walk warily henceforward. That frame-up has been concealed and elaborated by several people -notably one you heard speak right up before you, and in his own malice try to send this man to the rope. That's a pretty thought to take with you when you consider your verdict.
'But you have nothing to do with pity or sympathy. Your business is justice, plain justice, and that's all I'm asking for. Therefore I'm goin' to submit that the whole point of this case depends on two things: a piece of feather and a cross-bow.
'The Crown ask you to believe that this man - with no motive - suddenly grabbed an arrow down from the wall and stabbed Avory Hume. It's a simple case, and makes a simple issue. Either he did do that, or he didn't. If he did do that, he's guilty. If he unquestionably did not do it, he's unquestionably innocent.
'Take first the feather. When Dyer left the prisoner in that study, alone with Avory Hume, the feather was on the arrow - all of it - intact. That's a simple fact which hasn't been disputed by anyone, and the Attorney-General will acknowledge it to you. When the door was unbolted, and Dyer and Mr Fleming went into that room, half that feather was gone from the arrow. They searched the room immediately, and the feather was not there: that's also a simple fact. Inspector Mottram searched the room, and the feather was not there, and that's a simple fact too. All this time, you remember, the accused had not left the study.
'Where was the feather? The only suggestion the police can make is that it was unconsciously carried away in the prisoner's clothes. Now, I submit to you simply that this couldn't possibly be true. There are two reasons. First of all, you saw it demonstrated here that two people could not possibly tear that feather - in a struggle - in the way it was torn; therefore there wasn't any struggle, and what becomes of the prosecution's case on that score alone? Second, and even more important, we know where the feather actually was.
'You've heard it testified by the manager of the Left-Luggage Department at Paddington that a certain person - not the prisoner - left a suitcase at the station early in the evening of January 4th. (In any case, the prisoner was not in a position to go on any errands, having been under the eye of the police from the time the murder was discovered until the followin' morning.) That suitcase contained the cross-bow you've seen; and stuck into the teeth of the windlass was a big part of the missing piece of feather.