For a moment Couturier surveyed Lecoq with a knowing air, as if he hoped to discover whether he were speaking the truth or attempting to deceive him.  “I believe you,” he said at last.  “And to prove it I’ll tell you how it happened.  I was dining alone last evening in a restaurant in the Rue Mouffetard, when that man came in and took a seat beside me.  Naturally we began to talk; and I thought him a very good sort of a fellow.  I forget how it began, but somehow or other he mentioned that he had some clothes he wanted to sell; and being glad to oblige him, I took him to a friend, who bought them from him.  It was doing him a good turn, wasn’t it?  Well, he offered me something to drink, and I returned the compliment.  We had a number of glasses together, and by midnight I began to see double.  He then began to propose a plan, which, he swore, would make us both rich.  It was to steal the plate from a superb mansion.  There would be no risk for me; he would take charge of the whole affair.

“I had only to help him over the wall, and keep watch.  The proposal was tempting—­was it not?  You would have thought so, if you had been in my place, and yet I hesitated.  But the fellow insisted.  He swore that he was acquainted with the habits of the house; that Monday evening was a grand gala night there, and that on these occasions the servants didn’t lock up the plate.  After a little while I consented.”

A fleeting flush tinged Lecoq’s pale cheeks.  “Are you sure he told you that the Duc de Sairmeuse received every Monday evening?” he asked, eagerly.

“Certainly; how else could I have known it!  He even mentioned the name you uttered just now, a name ending in ‘euse.’”

A strange thought had just flitted through Lecoq’s mind.

“What if May and the Duc de Sairmeuse should be one and the same person?” But the notion seemed so thoroughly absurd, so utterly inadmissible that he quickly dismissed it, despising himself even for having entertained it for a single instant.  He cursed his inveterate inclination always to look at events from a romantic impossible side, instead of considering them as natural commonplace incidents.  After all there was nothing surprising in the fact that a man of the world, such as he supposed May to be, should know the day set aside by the Duc de Sairmeuse for the reception of his friends.

The young detective had nothing more to expect from Couturier.  He thanked him, and after shaking hands with the superintendent, walked away, leaning on Father Absinthe’s arm.  For he really had need of support.  His legs trembled, his head whirled, and he felt sick both in body and in mind.  He had failed miserably, disgracefully.  He had flattered himself that he possessed a genius for his calling, and yet he had been easily outwitted.

To rid himself of pursuit, May had only had to invent a pretended accomplice, and this simple stratagem had sufficed to nonplus those who were on his trail.