certainly found the way to make me stay, M. Guerchard."
"Yes, yes; stay, stay," said M. Gournay-Martin hastily. "It's an excellent idea, excellent. You're the very man to help M. Guerchard, Duke. You're an intrepid explorer, used to danger and resourceful, absolutely fearless."
"Do you really mean to say you're not going home to bed, Jacques?" said Germaine, disregarding her father's wish with her usual frankness.
"No; I'm going to stay with M. Guerchard," said the Duke slowly.
"Well, you will be fresh to go to the Princess's to-morrow night." said Germaine petulantly. "You didn't get any sleep at all last night, you couldn't have. You left Charmerace at eight o'clock; you were motoring all the night, and only got to Paris at six o'clock this morning."
"Motoring all night, from eight o'clock to six!" muttered Guerchard under his breath.
"Oh, that will be all right," said the Duke carelessly. "This interesting affair is to be over by midnight, isn't it?"
"Well, I warn you that, tired or fresh, you will have to come with me to the Princess's to-morrow night. All Paris will be there—all Paris, that is, who are in Paris."
"Oh, I shall be fresh enough," said the Duke.
They went out of the drawing-room and down the stairs, all four of them. There was an alert readiness about Guerchard, as if he were ready to spring. He kept within a foot of the Duke right to the front door. The detective in charge opened it; and they went down the steps to the taxi-cab which was awaiting them. The Duke kissed Germaine's fingers and handed her into the taxi-cab.
M. Gournay-Martin paused at the cab-door, and turned and said, with a pathetic air, "Am I never to sleep in my own house again?" He got into the cab and drove off.
The Duke turned and came up the steps, followed by Guerchard. In the hall he took his opera-hat and coat from the stand, and went upstairs. Half-way up the flight he paused and said:
"Where shall we wait for Lupin, M. Guerchard? In the drawing-room, or in M. Gournay-Martin's bedroom?"
"Oh, the drawing-room," said Guerchard. "I think it very unlikely that Lupin will look for the coronet in M. Gournay-Martin's bedroom. He would know very well that that is the last place to find it now."
The Duke went on into the drawing-room. At the door Guerchard stopped and said: "I will just go and post my men, your Grace."
"Very good," said the Duke; and he went into the drawing-room.
He sat down, lighted a cigarette, and yawned. Then he took out his watch and looked at it.
"Another twenty minutes," he said.
CHAPTER XIX
THE DUKE GOES
When Guerchard joined the Duke in the drawing-room, he had lost his calm air and was looking more than a little nervous. He moved about the room uneasily, fingering the bric-a-brac, glancing at the Duke and looking quickly away from him again. Then he came to a standstill on the hearth-rug with his back to the fireplace.
"Do you think it's quite safe to stand there, at least with your back to the hearth? If Lupin dropped through that opening suddenly, he'd catch you from behind before you could wink twice," said the Duke, in a tone of remonstrance.
"There would always be your Grace to come to my rescue," said Guerchard; and there was an ambiguous note in his voice, while his piercing eyes now rested fixed on the Duke's face. They seemed never to leave it; they explored, and explored it.
"It's only a suggestion," said the Duke.
"This is rather nervous work, don't you know."
"Yes; and of course you're hardly fit for it," said Guerchard. "If I'd known about your break-down in your car last night, I should have hesitated about asking you—"
"A break-down?" interrupted the Duke.
"Yes, you left Charmerace at eight o'clock last night. And you only reached Paris at six this morning. You couldn't have had a very high-power car?" said Guerchard.
"I had a 100 h.-p. car," said the Duke.
"Then you must have had a devil of a break-down," said Guerchard.
"Yes, it was pretty bad, but I've known worse," said the Duke carelessly. "It lost me about three hours: oh, at least three hours. I'm not a first-class repairer, though I know as much about an engine as most motorists."
"And there was nobody there to help you repair it?" said Guerchard.
"No; M. Gournay-Martin could not let me have his chauffeur to drive me to Paris, because he was keeping him to help guard the chateau. And of course there was nobody on the road, because it was two o'clock in the morning."
"Yes, there was no one," said Guerchard slowly.
"Not a soul," said the Duke.
"It was unfortunate," said Guerchard; and there was a note of incredulity in his voice.
"My having to repair the car myself?" said the Duke.
"Yes, of course," said Guerchard, hesitating a little over the assent.
The Duke dropped the end of his cigarette into a tray, and took out his case. He held it out towards Guerchard, and said, "A cigarette? or perhaps you prefer your caporal?"
"Yes, I do, but all the same I'll have one," said Guerchard, coming quickly across the room. And he took a cigarette from the case, and looked at it.
"All the same, all this is very curious," he said in a new tone, a challenging, menacing, accusing tone.
"What?" said the Duke, looking at him curiously.
"Everything: your cigarettes ... the salvias ... the photograph that Bonavent found in Victoire's prayer-book ... that man in motoring dress ... and finally, your break-down," said Guerchard; and the accusation and the threat rang clearer.
The Duke rose from his chair quickly and said haughtily, in icy tones: "M. Guerchard, you've been drinking!"
He went to the chair on which he had set his overcoat and his hat, and picked them up. Guerchard sprang in front of him, barring his way, and cried in a shaky voice: "No; don't go! You mustn't go!"
"What do you mean?" said the Duke, and paused. "What DO you mean?"
Guerchard stepped back, and ran his hand over his forehead. He was very pale, and his forehead was clammy to his touch:
"No ... I beg your pardon ... I beg your pardon, your Grace ... I must be going mad," he stammered.
"It looks very like it," said the Duke coldly.
"What I mean to say is," said Guerchard in a halting, uncertain voice, "what
