While he was speaking, the detective watched her narrowly. Certainly she was meditating some remarkable action. He wondered what it could be.
"Yes," said Nick, turning to the superintendent, "we have at last straightened out the matter of those two rooms and their occupants.
"As to the spot where the crime was committed, I have not been in doubt from the first.
"You will remember that the fatal wound was visible on both the woman's temples. The bullet passed entirely through her head.
"But where was the bullet? That was the question which I asked myself at once.
"I could not find it in room B, where the body lay. Then I tried room A, with no better success.
"At this point Chick took up the hunt, and carried it to the end. The bullet was in neither room. It was just between them.
"You remember that there was a door which I found fastened upon both sides.
"Chick opened that door, and in its framework, the wood of which was old and soft, he found the bullet.
"The mark was covered when the door was shut. Therefore the door must have been open when the shot was fired.