The detectives had already distributed themselves on every side to bar the fugitive’s road.  It soon became manifest that Florence, for whom they were hunting on the ground floor and in the basement, had gone from the yard into the room underneath her own, which happened to be the mother superior’s; that she had put on a nun’s habit; and that, thus disguised, she had passed unnoticed through the very men who were pursuing her.

They rushed outside.  But it was now dark; and every search was bound to be vain in so populous a quarter.

The Prefect of Police made no effort to conceal his displeasure.  Don Luis was also greatly disappointed at this flight, which thwarted his plans, and enlarged openly upon Weber’s lack of skill.

“I told you so, Deputy Chief!  You should have taken your precautions.  Mlle. Levasseur’s attitude ought to have warned you.  She evidently knows the criminal and wanted to go to him, ask him for explanations and, for all we can tell, save him, if he managed to convince her.  And what will happen between them?  When the villain sees that he is discovered, he will be capable of anything.”

M. Desmalions again questioned the mother superior and soon learned that Florence, before taking refuge in the nursing-home, had spent forty-eight hours in some furnished apartments on the Ile Saint-Louis.

The clue was not worth much, but they could not neglect it.  The Prefect of Police, who retained all his doubts with regard to Florence and attached extreme importance to the girl’s capture, ordered Weber and his men to follow up this trail without delay.  Don Luis accompanied the deputy chief.

Events at once showed that the Prefect of Police was right.  Florence had taken refuge in the lodging-house on the Ile Saint-Louis, where she had engaged a room under an assumed name.  But she had no sooner arrived than a small boy called at the house, asked for her, and went away with her.

They went up to her room and found a parcel done up in a newspaper, containing a nun’s habit.  The thing was obvious.

Later, in the course of the evening, Weber succeeded in discovering the small boy.  He was the son of the porter of one of the houses in the neighbourhood.  Where could he have taken Florence?  When questioned, he definitely refused to betray the lady who had trusted him and who had cried when she kissed him.  His mother entreated him.  His father boxed his ears.  He was inflexible.

In any case, it was not unreasonable to conclude that Florence had not left the Ile Saint-Louis or its immediate vicinity.  The detectives persisted in their search all the evening.  Weber established his headquarters in a tap room where every scrap of information was brought to him and where his men returned from time to time to receive his orders.  He also remained in constant communication with the Prefect’s office.

At half-past ten a squad of detectives, sent by the Prefect, placed themselves at the deputy chief’s disposal.  Mazeroux, newly arrived from Rouen and furious with Florence, joined them.