“ Très bien. The affair marches, does it not? But matters were still obscure. What was the advantage of having the crime discovered that night in preference to the following morning? The only idea I could get hold of was that the murderer, knowing the crime was to be discovered at a certain time, could make sure of being present when the door was broken in⁠—or at any rate immediately afterwards. And now we come to the second fact⁠—the chair pulled out from the wall. Inspector Raglan dismissed that as of no importance. I, on the contrary, have always regarded it as of supreme importance.

“In your manuscript you have drawn a neat little plan of the study. If you had it with you this minute you would see that⁠—the chair being drawn out in the position indicated by Parker⁠—it would stand in a direct line between the door and the window.”

“The window!” I said quickly.