Suddenly, some weeks before the events with which we are occupied, a report—to which nobody attached any importance, so incredible did it sound—was spread about Paris, that Mademoiselle Stangerson had at last consented to “crown” the inextinguishable flame of Monsieur Robert Darzac! It needed that Monsieur Robert Darzac himself should not deny this matrimonial rumour to give it an appearance of truth, so unlikely did it seem to be well founded. One day, however, Monsieur Stangerson, as he was leaving the Academy of Science, announced that the marriage of his daughter and Monsieur Robert Darzac would be celebrated in the privacy of the Château du Glandier, as soon as he and his daughter had put the finishing touches to their report summing up their labours on the “Dissociation of Matter.” The new household would install itself in the Glandier, and the son-in-law would lend his assistance in the work to which the father and daughter had dedicated their lives. The scientific world had barely had time to recover from the effect of this news, when it learned of the attempted assassination of Mademoiselle under the extraordinary conditions which we have detailed and which our visit to the château was to enable us to ascertain with yet greater precision. I have not hesitated to furnish the reader with all these retrospective details, known to me through my business relations with Monsieur Robert Darzac. On crossing the threshold of “The Yellow Room” he was as well posted as I was. Chapter V In Which Joseph Rouletabille Makes a Remark to Monsieur Robert Darzac Which Produces its Little Effect Rouletabille and I had been walking for several minutes, by the side of a long wall bounding the vast property of Monsieur Stangerson and had already come within sight of the entrance gate, when our attention was drawn to an individual who, half bent to the ground, seemed to be so completely absorbed in what he was doing as not to have seen us coming towards him. At one time he stooped so low as almost to touch the ground; at another he drew himself up and attentively examined the wall; then he looked into the palm of one of his hands, and walked away with rapid strides. Finally he set off running, still looking into the palm of his hand. Rouletabille had brought me to a standstill by a gesture. “Hush! Frédéric Larsan is at work! Don’t let us disturb him!” Rouletabille had a great admiration for the celebrated detective. I had never before seen him, but I knew him well by reputation. At that time, before Rouletabille had given proof of his unique talent, Larsan was reputed as the most skilful unraveller of the most mysterious and complicated crimes. His reputation was world-wide, and the police of London, and even of America, often called him in to their aid when their own national inspectors and detectives found themselves at the end of their wits and resources.