Perenna, who passed him a slip of paper, saying:

"Mme. d'Ersingen's telephone number."

M. Desmalions murmured:

"Yes, true, they may know--"

And, taking down the receiver, he asked for number 325.04. He was
connected at once and continued:

"Who is that speaking?... The butler? Ah! Is Mme. d'Ersingen at
home?... No?... Or Monsieur?... Not he, either?... Never mind, you can
tell me what I want to know. I am M. Desmalions, the Prefect of Police,
and I need certain information. At what time did Mme. Fauville come last
night?... What do you say?... Are you sure?... At two o'clock in the
morning?... Not before?... And she went away?... In ten minutes
time?... Good ... But you're certain you are not mistaken about the
time when she arrived? I must know this positively: it is most
important.... You say it was two o'clock in the morning? Two o'clock in
the morning?... Very well.... Thank you."

When M. Desmalions turned round, he saw Mme. Fauville standing beside him
and looking at him with an expression of mad anguish. And one and the
same idea occurred to the mind of all the onlookers. They were in the
presence either of an absolutely innocent woman or else of an exceptional
actress whose face lent itself to the most perfect simulation of
innocence.

"What do you want?" she stammered. "What does this mean? Explain
yourself!"

Then M. Desmalions asked simply:

"What were you doing last night between half-past eleven in the evening
and two o'clock in the morning?"

It was a terrifying question at the stage which the examination had
reached, a fatal question implying:

"If you cannot give us an exact and strict account of the way in which
you employed your time while the crime was being committed, we have the
right to conclude that you were not alien to the murder of your husband
and stepson--"

She understood it in this sense and staggered on her feet, moaning:

"It's horrible!... horrible!"

The Prefect repeated:

"What were you doing? The question must be quite easy to answer."

"Oh," she cried, in the same piteous tone, "how can you believe!... Oh,
no, no, it's not possible! How can you believe!"

"I believe nothing yet," he said. "Besides, you can establish the truth
with a single word."

It seemed, from the movement of her lips and the sudden gesture of
resolution that shook her frame, as though she were about to speak that
word. But all at once she appeared stupefied and dumfounded, pronounced a