"Why, man, can't you see? While the train is travelling express, every one must stay on board it; if it slows, it is possible to leave it."

"Who would want to leave it?"

"Oh, I don't know," said the General, rather testily. "Any way, the thing's done now."

The train had pulled up in obedience to the signal of alarm given by some one in the sleeping-car, but by whom it was impossible to say. Not by the porter, for he seemed greatly surprised as the conductor came up to him.

"How did you know?" he asked.

"Know! Know what? You stopped me."

"I didn't."

"Who rang the bell, then?"

"I did not. But I'm glad you've come. There has been a crime-murder."

"Good Heavens!" cried the conductor, jumping up on to the car, and entering into the situation at once. His business was only to verify the fact, and take all necessary precautions. He was a burly, brusque, peremptory person, the despotic, self-important French official, who knew what to do-as he thought-and did it without hesitation or apology.

"No one must leave the car," he said in a tone not to be misunderstood. "Neither now, nor on arrival at the station."

There was a shout of protest and dismay, which he quickly cut short.

"You will have to arrange it with the authorities in Paris; they can alone decide. My duty is plain: to detain you, place you under surveillance till then. Afterwards, we will see. Enough, gentlemen and madame-"

He bowed with the instinctive gallantry of his nation to the female figure which now appeared at the door of her compartment. She stood for a moment listening, seemingly greatly agitated, and then, without a word, disappeared, retreating hastily into her own private room, where she shut herself in.

Almost immediately, at a signal from the conductor, the train resumed its journey.