question is, what is the secret of this terrible influence he
has gained over her? I have positive proof that they have not met
since their early youth until fifteen months ago; and, as Mme. Fauvel's
reputation has always been above the reach of slander, we must seek in
the past for the cause of her resigned obedience to his will."

"We can never discover it," said Prosper mournfully.

"We can discover it as soon as we know Clameran's past life. Ah,
to-night he turned as white as a sheet when I mentioned his brother
Gaston's name. And then I remembered that Gaston died suddenly, while
his brother Louis was making a visit."

"Do you think he was murdered?"

"I think the men who tried to assassinate me would do anything. The
robbery, my friend, has now become a secondary detail. It is quite
easily explained, and, if that were all to be accounted for, I would say
to you, My task is done, let us go ask the judge of instruction for a
warrant of arrest."

Prosper started up with sparkling eyes.

"Ah, you know--is it possible?"

"Yes, I know who gave the key, and I know who told the secret word."

"The key might have been M. Fauvel's. But the word----"

"The word you were foolish enough to give. You have forgotten, I
suppose. But fortunately Gypsy remembered. You know that, two days
before the robbery, you took Lagors and two other friends to sup with
Mme. Gypsy? Nina was sad, and reproached you for not being more devoted
to her."

"Yes, I remember that."

"But do you remember what you replied to her?"

"No, I do not," said Prosper after thinking a moment.

"Well, I will tell you: 'Nina, you are unjust in reproaching me with
not thinking constantly of you; for at this very moment your dear name
guards M. Fauvel's safe.'"

The truth suddenly burst upon Prosper like a thunderclap. He wrung his
hands despairingly, and cried:

"Yes, oh, yes! I remember now."

"Then you can easily understand the rest. One of the scoundrels went to
Mme. Fauvel, and compelled her to give up her husband's key; then, at
a venture, placed the movable buttons on the name of Gypsy, opened the
safe, and took the three hundred and fifty thousand francs. And Mme.
Fauvel must have been terribly frightened before she yielded. The day
after the robbery the poor woman was near dying; and it was she who at
the greatest risk sent you the ten thousand francs."

"But which was the thief, Raoul or Clameran? What enables them to thus
tyrannize ov