He hastened to withdraw attention from the scratch upon the lock.

"To conclude," he said, addressing the commissary, "I am convinced that
no one outside of the bank could have obtained access to this room. The
safe, moreover, is intact. No suspicious pressure has been used on the
movable buttons. I can assert that the lock has not been tampered with
by burglar's tools or false keys. Those who opened the safe knew the
word, and possessed the key."

This formal affirmation of a man whom he knew to be skilful ended the
hesitation of the commissary.

"That being the case," he replied, "I must request a few moments'
conversation with M. Fauvel."

"I am at your service," said the banker.

Prosper foresaw the result of this conversation. He quietly placed his
hat on the table, to show that he had no intention of attempting to
escape, and passed into the adjoining room.

Fanferlot also went out, but not before the commissary had made him a
sign, and received one in return.

This sign signified, "You are responsible for this man."

The detective needed no admonition to make him keep a strict watch. His
suspicions were too vague, his desire for success was too ardent, for
him to lose sight of Prosper an instant.