Without losing a minute, Lecoq hastened to this individual’s office.  M. Petit remembered the Watchau sale very well; it had made quite a sensation at the time, and on searching among his papers he soon found a long catalogue of the various articles sold.  Several lots of jewelry were mentioned, with the sums paid, and the names of the purchasers; but there was not the slightest allusion to these particular earrings.  When Lecoq produced the diamond he had in his pocket, the auctioneer could not remember that he had ever seen it; though of course this was no evidence to the contrary, for, as he himself remarked,—­so many articles passed through his hands!  However, this much he could declare upon oath; the baroness’s brother, her only heir, had preserved nothing—­not so much as a pin’s worth of his sister’s effects:  although he had been in a great hurry to receive the proceeds, which amounted to the pleasant sum of one hundred and sixty-seven thousand five hundred and thirty francs, all expenses deducted.

“Everything this lady possessed was sold?” inquired Lecoq.

“Everything.”

“And what is the name of this brother of hers?”

“Watchau, also.  The baroness had probably married one of her relatives.  Until last year her brother occupied a very prominent diplomatic position.  I think he now resides at Berlin.”

Certainly this information would not seem to indicate that the auctioneer had been tampered with; and yet Lecoq was not satisfied.  “It is very strange,” he thought, as he walked toward his lodgings, “that whichever side I turn, in this affair, I find mention of Germany.  The murderer comes from Leipsic, Madame Milner must be a Bavarian, and now here is an Austrian baroness.”

It was too late to make any further inquiries that evening, and Lecoq went to bed; but the next morning, at an early hour, he resumed his investigations with fresh ardor.  There now seemed only one remaining clue to success:  the letter signed “Lacheneur,” which had been found in the pocket of the murdered soldier.  This letter, judging from the half-effaced heading at the top of the note-paper, must have been written in some cafe on the Boulevard Beaumarchais.  To discover which precise cafe would be mere child’s play; and indeed the fourth landlord to whom Lecoq exhibited the letter recognized the paper as his.  But neither he, nor his wife, nor the young lady at the counter, nor the waiters, nor any of the customers present at the time, had ever once heard mention made of this singular name—­Lacheneur.

And now what was Lecoq to do?  Was the case utterly hopeless?  Not yet.  Had not the spurious soldier declared that this Lacheneur was an old comedian?  Seizing upon this frail clue, as a drowning man clutches at the merest fragment of the floating wreck, Lecoq turned his steps in another direction, and hurried from theatre to theatre, asking every one, from doorkeeper to manager:  “Don’t you know an actor named Lacheneur?”