“There were no stamps in his desk, but there might have been, eh, mon ami ? There might have been? Yes”⁠—his eyes wandered round the room⁠—“this boudoir has nothing more to tell us. It did not yield much. Only this.”

He pulled a crumpled envelope out of his pocket, and tossed it over to me. It was rather a curious document. A plain, dirty looking old envelope with a few words scrawled across it, apparently at random. The following is a facsimile of it.