“The curtains were drawn, sir, and the electric light was on.”

Poirot nodded approval. “Anything else?”

“Yes, sir, this chair was drawn out a little more.”

He indicated a big grandfather chair to the left of the door between it and the window. I append a plan of the room with the chair in question marked with an X.

“Just show me,” said Poirot.

The butler drew the chair in question out a good two feet from the wall, turning it so that the seat faced the door.

“ Voilà ce qui est curieux ,” murmured Poirot. “No one would want to sit in a chair in such a position, I fancy. Now who pushed it back into place again, I wonder? Did you, my friend?”