“I pity you if you are going to the marchioness’s house to collect a bill,” he remarked to Lecoq.  “You will have plenty of time to learn the way here before you see your money.  You will only be another of the many creditors who never let her bell alone.”

“The deuce!  Is she as poor as that?”

“Poor!  Why, every one knows that she has a comfortable income, without counting this house.  But when one spends double one’s income every year, you know—­”

The landlord stopped short, to call Lecoq’s attention to two ladies who were passing along the street, one of them, a woman of forty, dressed in black; the other, a girl half-way through her teens.  “There,” quoth the wine-seller, “goes the marchioness’s granddaughter, Mademoiselle Claire, with her governess, Mademoiselle Smith.”

Lecoq’s head whirled.  “Her granddaughter!” he stammered.

“Yes—­the daughter of her deceased son, if you prefer it.”

“How old is the marchioness, then?”

“At least sixty:  but one would never suspect it.  She is one of those persons who live a hundred years.  And what an old wretch she is too.  She would think no more of knocking me over the head than I would of emptying this glass of wine—­”

“Excuse me,” interrupted Lecoq, “but does she live alone in that great house?”

“Yes—­that is—­with her granddaughter, the governess, and two servants.  But what is the matter with you?”

This last question was not uncalled for; for Lecoq had turned deadly white.  The magic edifice of his hopes had crumbled beneath the weight of this man’s words as completely as if it were some frail house of cards erected by a child.  He had only sufficient strength to murmur:  “Nothing—­nothing at all.”

Then, as he could endure this torture of uncertainty no longer, he went toward the marchioness’s house and rang the bell.  The servant who came to open the door examined him attentively, and then announced that Madame d’Arlange was in the country.  He evidently fancied that Lecoq was a creditor.

But the young detective insisted so adroitly, giving the lackey to understand so explicitly that he did not come to collect money, and speaking so earnestly of urgent business, that the servant finally admitted him to the hall, saying that he would go and see if madame had really gone out.

Fortunately for Lecoq, she happened to be at home, and an instant afterward the valet returned requesting the young detective to follow him.  After passing through a large and magnificently furnished drawing-room, they reached a charming boudoir, hung with rose-colored curtains, where, sitting by the fireside, in a large easy-chair, Lecoq found an old woman, tall, bony, and terrible of aspect, her face loaded with paint, and her person covered with ornaments.  The aged coquette was Madame, the Marchioness, who, for the time being, was engaged in knitting a strip of green wool.  She turned toward her visitor just enough to show him the rouge on one cheek, and then, as he seemed rather frightened—­a fact flattering to her vanity—­she spoke in an affable tone.  “Ah, well young man,” said she, “what brings you here?”