A theory had half formed itself in Lecoq’s brain.  He determined to prove its truth.  Disguised as a clown, he attended the fancy-dress ball, and in the character of a mountebank collected a group of ladies and gentlemen around him while he related with the inimitable skill of a buffoon a romantic narrative.  To most of the people present it was simply an amusing story, but to the count and Lagors and Madame Fauvel, who were among the listeners, it seemed something much more, for Lecoq dressed out his theory of the robbery in the trappings of romance.  Just as he reached the climax of the story there was a cry, and Madame Fauvel almost fell fainting on the floor.  The count and Lagors rushed up furiously to Lecoq.

“Master Clown,” said Lagors, “your tongue is too long.”

“Perhaps, my pretty boy,” retorted Lecoq, “perhaps it is.  But it is, I can assure you, not so long as my arm.”

“Who are you, M. le Clown?” the count exclaimed angrily.

“I am,” replied Lecoq, “the best friend your brother Gaston had.  I was his counsellor.  I am the confidant of his last wishes.”

Though the solution of the problem seemed so tantalisingly near, there were still some threads in the tangle which required sorting out before Lecoq could say that the case was complete.  Among other matters he inquired of Bertomy the word which had been used to lock the safe on, the night of the robbery.  The word had been “gipsy.”  Bertomy was confident that he had not mentioned it to anybody, but Nina Gipsy was able to throw light on this part of the problem.  She recollected a chance remark of Bertomy’s while sitting at dinner with herself and Lagors on the night of the robbery.  She had reproached Bertomy with neglecting her.

“It’s too bad for you to reproach me,” cried the cashier, “for it is your name which at this very moment guards the safe of M. Fauvel.”

Lagors, therefore, had known the password.  What did this new discovery imply?  How did it fit in with the rest of the data which Lecoq had so brilliantly collected?

After his custom, he marshalled once more in his mind all the facts at his disposal, but they were like so many loose links in a chain.  They required the connecting link to make the chain complete.  To find that link Lecoq spent a month in visiting the old home of the De Clamerans, the estate formerly occupied by Gaston de Clameron, who had died a few days before the robbery, and also in a trip to England.  When he returned to Paris, dossier No. 113 was complete.

III.—­The Dossier

In her extreme youth, Madame Fauvel had been secretly loved by Gaston de Clameron.  It was a result of certain contemptuous words spoken of the girl he loved that Gaston had committed those deeds which had compelled him to fly the country.  Shortly after his flight, the girl, finding that she was about to give birth to a child, imparted the secret to her mother.  Fearing a scandal, the mother, accompanied by a faithful nurse, took her daughter over to England.  There, near London, a child was born, who was immediately handed over to some simple country people to adopt.  The unhappy girl returned to France, and shortly after married M. Fauvel, the banker.