“Ah, yes, I know, I know!” said Lecoq.

“The thief,” resumed the sergeant, “walked into a pretty trap when he got over that wall.  There was a reception at the mansion this evening, as there is every Monday, and every one in the house is still up.  The guests are only just leaving, for there were five or six carriages still at the door as we passed by.”

Lecoq darted off extremely troubled by what he had just heard.  It now seemed to him that if May had got into this garden, it was not for the purpose of committing a robbery, but in the hope of throwing his pursuers off the track, and making his escape by way of the Rue de Grenelle, which he hoped to do unnoticed, in the bustle and confusion attending the departure of the guests.

On reaching the Hotel de Sairmeuse, a princely dwelling, the long facade of which was brilliantly illuminated, Lecoq found a last carriage just coming from the courtyard, while several footmen were extinguishing the lights, and an imposing “Suisse,” dazzling to behold in his gorgeous livery, prepared to close the heavy double doors of the grand entrance.

The young detective advanced toward this important personage:  “Is this the Hotel de Sairmeuse?” he inquired.

The Suisse suspended his work to survey the audacious vagabond who ventured to question him, and then in a harsh voice replied:  “I advise you to pass on.  I want none of your jesting.”

Lecoq had forgotten that he was clad as a barriere loafer.  “Ah,” he rejoined, “I’m not what I seem to be.  I’m an agent of the secret service; by name Lecoq.  Here is my card, and I came to tell you that an escaped criminal has just scaled the garden wall in the rear of the Hotel de Sairmeuse.”

“A crim-in-al?”

The young detective thought a little exaggeration could do no harm, and might perhaps insure him more ready aid.  “Yes,” he replied; “and one of the most dangerous kind—­a man who has the blood of three victims already on his hands.  We have just arrested his accomplice, who helped him over the wall.”

The flunky’s ruby nose paled perceptibly.  “I will summon the servants,” he faltered, and suiting the action to the word, he was raising his hand to the bell-chain, employed to announce the arrival of visitors, when Lecoq hastily stopped him.

“A word first!” said he.  “Might not the fugitive have passed through the house and escaped by this door, without being seen?  In that case he would be far away by this time.”

“Impossible!”

“But why?”

“Excuse me, but I know what I am saying.  First, the door opening into the garden is closed; it is only open during grand receptions, not for our ordinary Monday drawing-rooms.  Secondly, Monseigneur requires me to stand on the threshold of the street door when he is receiving.  To-day he repeated this order, and you may be sure that I haven’t disobeyed him.”

“Since that’s the case,” said Lecoq, slightly reassured, “we shall perhaps succeed in finding our man.  Warn the servants, but without ringing the bell.  The less noise we make, the greater will be our chance of success.”