Yes, he has made a mistake. Yes, his reading of the doc.u.ment is all wrong. The word aiguille does not point to the castle on the Creuse. Also, the word demoiselles cannot be applied to Raymonde de Saint-Veran and her cousin, because the text of the doc.u.ment dates back for centuries.

Therefore, all must be done over again, from the beginning.

How?

One piece of evidence alone would be incontestible: the book published under Louis XIV. Now of those hundred copies printed by the person who was presumed to be the Man with the Iron Mask only two escaped the flames. One was purloined by the captain of the guards and lost. The other was kept by Louis XIV., handed down to Louis XV., and burnt by Louis XVI. But a copy of the essential page, the page containing the solution of the problem, or at least a cryptographic solution, was conveyed to Marie Antoinette, who slipped it into the binding of her book of hours. What has become of this paper? Is it the one which Beautrelet has held in his hands and which Lupin recovered from him through Bredoux, the magistrate's clerk? Or is it still in Marie Antoinette's book of hours? And the question resolves itself into this: what has become of the Queen's book of hours?

After taking a short rest, Beautrelet consulted his friend's father, an old and experienced collector, who was often called upon officially to give an expert opinion and who had quite lately been invited to advise the director of one of our museums on the drawing up of the catalogue.

"Marie Antoinette's book of hours?" he exclaimed. "Why, the Queen left it to her waiting-woman, with secret instructions to forward it to Count Fersen. After being piously preserved in the count's family, it has been, for the last five years, in a gla.s.s case-"

"A gla.s.s case?"

"In the Musee Carnavalet, quite simply."

"When will the museum be open?"

"At twenty minutes from now, as it is every morning."

Isidore and his friend jumped out of a cab at the moment when the doors of Madame de Sevigne's old mansion were opening.

"Hullo! M. Beautrelet!"

A dozen voices greeted his arrival. To his great surprise, he recognized the whole crowd of reporters who were following up "the mystery of the Hollow Needle." And one of them exclaimed:

"Funny, isn't it, that we should all have had the same idea? Take care, a.r.s.ene Lupin may be among us!"

They entered the museum together. The director was at once informed, placed himself entirely at their disposal, took them to the gla.s.s case and skewed them a poor little volume, devoid of all ornament, which certainly had nothing royal about it. Nevertheless, they were overcome by a certain emotion at the sight of this object which the Queen had touched in those tragic days, which her eyes, red with tears, had looked upon-And they dared not take it and hunt through it: it was as though they feared lest they should be guilty of a sacrilege-

"Come, M. Beautrelet, it's your business!"

He took the book with an anxious gesture. The description corresponded with that given by the author of the pamphlet. Outside was a parchment cover, dirty, stained and worn in places, and under it, the real binding, in stiff leather. With what a thrill Beautrelet felt for the hidden pocket! Was it a fairy tale? Or would he find the doc.u.ment written by Louis XVI. and bequeathed by the queen to her fervent admirer?

At the first page, on the upper side of the book, there was no receptacle.

"Nothing," he muttered.

"Nothing," they echoed, palpitating with excitement.

But, at the last page, forcing back the book a little, he at once saw that the parchment was not stuck to the binding. He slipped his fingers in between-there was something-yes, he felt something-a paper-

"Oh!" he gasped, in an accent almost of pain. "Here-is it possible?"

"Quick, quick!" they cried. "What are you waiting for?"

He drew out a sheet folded in two.

"Well, read it!-There are words in red ink-Look!-it might be blood-pale, faded blood-Read it!-"

He read:

To you, Fersen. For my son. 16 October, 1793.

MARIE ANTOINETTE.

And suddenly Beautrelet gave a cry of stupefaction. Under the queen's signature there were-there were two words, in black ink, underlined with a flourish-two words:

a.r.s.eNE LUPIN.

All, in turns, took the sheet of paper and the same cry escaped from the lips of all of them:

"Marie Antoinette!-a.r.s.ene Lupin!"

A great silence followed. That double signature: those two names coupled together, discovered hidden in the book of hours; that relic in which the poor queen's desperate appeal had slumbered for more than a century: that horrible date of the 16th of October, 1793, the day on which the Royal head fell: all of this was most dismally and disconcertingly tragic.

"a.r.s.ene Lupin!" stammered one of the voices, thus emphasizing the scare that underlay the sight of that demoniacal name at the foot of the hallowed page.

"Yes, a.r.s.ene Lupin," repeated Beautrelet. "The Queen's friend was unable to understand her desperate dying appeal. He lived with the keepsake in his possession which the woman whom he loved had sent him and he never guessed the reason of that keepsake. Lupin discovered everything, on the other hand-and took it."

"Took what?"

"The doc.u.ment, of course! The doc.u.ment written by Louis XVI.; and it is that which I held in my hands. The same appearance, the same shape, the same red seals. I understand why Lupin would not leave me a doc.u.ment which I could turn to account by merely examining the paper, the seals and so on."

"And then?"

"Well, then, since the doc.u.ment is genuine, since I have, with my own eyes, seen the marks of the red seals, since Marie Antoinette herself a.s.sures me, by these few words in her hand, that the whole story of the pamphlet, as printed by M. Ma.s.siban, is correct, because a problem of the Hollow Needle really exists, I am now certain to succeed."

"But how? Whether genuine or not, the doc.u.ment is of no use to you if you do not manage to decipher it, because Louis XVI. destroyed the book that gave the explanation."

"Yes, but the other copy, which King Louis XVI.'s captain of the guards s.n.a.t.c.hed from the flames, was not destroyed."

"How do you know?"

"Prove the contrary."

After uttering this defiance, Beautrelet was silent for a time and then, slowly, with his eyes closed, as though trying to fix and sum up his thoughts, he said:

"Possessing the secret, the captain of the guards begins by revealing it bit by bit in the journal found by his descendant. Then comes silence. The answer to the riddle is withheld. Why? Because the temptation to make use of the secret creeps over him little by little and he gives way to it. A proof? His murder. A further proof? The magnificent jewel found upon him, which he must undoubtedly have taken from some royal treasure the hiding-place of which, unknown to all, would just const.i.tute the mystery of the Hollow Needle. Lupin conveyed as much to me; Lupin was not lying."

"Then what conclusion do you draw, Beautrelet?"

"I draw this conclusion, my friends, that it be a good thing to advertise this story as much as possible, so that people may know, through all the papers, that we are looking for a book ent.i.tled The Treatise of the Needle. It may be fished out from the back shelves of some provincial library."

The paragraph was drawn up forthwith; and Beautrelet set to work at once, without even waiting for it to produce a result. A first scent suggested itself: the murder was committed near Gaillon. He went there that same day. Certainly, he did not hope to reconstruct a crime perpetrated two hundred years ago. But, all the same, there are crimes that leave traces in the memories, in the traditions of a countryside. They are recorded in the local chronicles. One day, some provincial archaeologist, some lover of old legends, some student of the minor incidents of the life of the past makes them the subject of an article in a newspaper or of a communication to the academy of his departmental town.

Beautreiet saw three or four of these archaeologists. With one of them in particular, an old notary, he examined the prison records, the ledgers of the old bailiwicks and the parish registers. There was no entry referring to the murder of a captain of the guards in the seventeenth century.

He refused to be discouraged and continued his search in Paris, where the magistrate's examination might have taken place. His efforts came to nothing.