o
make sure to impress it on that part of my brain where I have drawn my
circle of reasoning."

The landlady re-appeared at that moment, bringing in the traditional
bacon omelette. Rouletabille chaffed her a little, and she took the
chaff with the most charming good humour.

"She is much jollier when Daddy Mathieu is in bed with his rheumatism,"
Rouletabille said to me.

But I had eyes neither for Rouletabille nor for the landlady's smiles.
I was entirely absorbed over the last words of my young friend and in
thinking over Monsieur Robert Darzac's strange behaviour.

When he had finished his omelette and we were again alone, Rouletabille
continued the tale of his confidences.

"When I sent you my telegram this morning," he said, "I had only
the word of Monsieur Darzac, that 'perhaps' the assassin would come
to-night. I can now say that he will certainly come. I expect him."

"What has made you feel this certainty?"

"I have been sure since half-past ten o'clock this morning that he
would come. I knew that before we saw Arthur Rance at the window in the
court."

"Ah!" I said, "But, again--what made you so sure? And why since
half-past ten this morning?"

"Because, at half-past ten, I had proof that Mademoiselle Stangerson was
making as many efforts to permit of the murderer's entrance as Monsieur
Robert Darzac had taken precautions against it."

"Is that possible!" I cried. "Haven't you told me that Mademoiselle
Stangerson loves Monsieur Robert Darzac?"

"I told you so because it is the truth."

"Then do you see nothing strange--"

"Everything in this business is strange, my friend; but take my word for
it, the strangeness you now feel is nothing to the strangeness that's to
come!"

"It must be admitted, then," I said, "that Mademoiselle Stangerson and
her murderer are in communication--at any rate in writing?"

"Admit it, my friend, admit it! You don't risk anything! I told you
about the letter left on her table, on the night of the inexplicable
gallery affair,--the letter that disappeared into the pocket of
Mademoiselle Stangerson. Why should it not have been a summons to a
meeting? Might he not, as soon as he was sure of Darzac's absence,
appoint the meeting for 'the coming night?"

And my friend laughed silently. There are moments when I ask myself if
he is not laughing at me.

The door of the inn opened. Rouletabille was on his feet so suddenly
that one might have thought he had received an el