"You did."
"I was in the library. Mark went in—he may have come out again—I know nothing. Somebody else may have gone in—"
"Yes, yes," said Antony patiently, as if to a little child. "You know your cousin; I don't. Let's agree that he had nothing to do with it. But somebody was in the room when this man was shot, and—well, the police will have to know. Don't you think—" He looked at the telephone. "Or would you rather I did it?"
Cayley shrugged his shoulders and went to the telephone.
"May I—er—look round a bit?" Antony nodded towards the open door.
"Oh, do. Yes." He sat down and drew the telephone towards him. "You must make allowances for me, Mr. Gillingham. You see, I've known Mark for a very long time. But, of course, you're quite right, and I'm merely being stupid." He took off the receiver.
Let us suppose that, for the purpose of making a first acquaintance with this "office," we are coming into it from the hall, through the door which is now locked, but which, for our special convenience, has been magically unlocked for us. As we stand just inside the door, the length of the room runs right and left; or, more accurately, to the right only, for the left-hand wall is almost within our reach.
