“Ah, ha!” he laughed, as Lecoq passed out, “here is one of those simpletons who fish for whales and do not catch even a gudgeon.”

For an instant Lecoq was angry.  He turned abruptly and looked Gevrol full in the face.

“That is better than assisting prisoners to carry on a surreptitious correspondence with people outside,” he retorted, in the tone of a man who knows what he is saying.

In his surprise, Gevrol almost lost countenance, and his blush was equivalent to a confession.

But Lecoq said no more.  What did it matter to him now if Gevrol had betrayed him!  Was he not about to win a glorious revenge?

He spent the remainder of the day in preparing his plan of action, and in thinking what he should say when he took M. Segmuller’s note to Maurice d’Escorval.

The next morning about eleven o’clock he presented himself at the house of M. d’Escorval.

“Monsieur is in his study with a young man,” replied the servant; “but, as he gave me no orders to the contrary, you may go in.”

Lecoq entered.

The study was unoccupied.  But from the adjoining room, separated from the study only by a velvet portiere, came a sound of stifled exclamations, and of sobs mingled with kisses.

Not knowing whether to remain or retire, the young policeman stood for a moment undecided; then he observed an open letter lying upon the carpet.

Impelled to do it by an impulse stronger than his own will, Lecoq picked up the letter.  It read as follows: 

“The bearer of this letter is Marie-Anne’s son, Maurice—­your son.  I have given him all the proofs necessary to establish his identity.  It was to his education that I consecrated the heritage of my poor Marie-Anne.

“Those to whose care I confided him have made a noble man of him.  If I restore him to you, it is only because the life I lead is not a fitting life for him.  Yesterday, the miserable woman who murdered my sister died from poison administered by her own hand.  Poor Marie-Anne! she would have been far more terribly avenged had not an accident which happened to me, saved the Duc and the Duchesse de Sairmeuse from the snare into which I had drawn them.

“Jean Lacheneur.”

Lecoq stood as if petrified.

Now he understood the terrible drama which had been enacted in the Widow Chupin’s cabin.

“I must go to Sairmeuse at once,” he said to himself; “there I can discover all.”

He departed without seeing M. d’Escorval.  He resisted the temptation to take the letter with him.

It was exactly one month to a day after the death of Mme. Blanche.

Reclining upon a divan in his library the Duc de Sairmeuse was engaged in reading, when Otto, his valet de chambre, came to inform him that a messenger was below, charged with delivering into the duke’s own hands a letter from M. Maurice d’Escorval.