Rouletabille shrugged his shoulders.

"Is there nothing in this article in the 'Matin' by which you were
particularly struck?"

"Nothing,--I have found the whole of the story it tells equally
strange."

"Well, but--the locked door--with the key on the inside?"

"That's the only perfectly natural thing in the whole article."

"Really!--And the bolt?"

"The bolt?"

"Yes, the bolt--also inside the room--a still further protection
against entry? Mademoiselle Stangerson took quite extraordinary
precautions! It is clear to me that she feared someone. That was
why she took such precautions--even Daddy Jacques's revolver
--without telling him of it. No doubt she didn't wish to alarm
anybody, and least of all, her father. What she dreaded took place,
and she defended herself. There was a struggle, and she used the
revolver skilfully enough to wound the assassin in the hand--which
explains the impression on the wall and on the door of the large,
blood-stained hand of the man who was searching for a means of
exit from the chamber. But she didn't fire soon enough to avoid
the terrible blow on the right temple."