The idea came to him quite unexpectedly while the Prussians were at their supper. In another he would have scoffed at it, but Sadi had long been fretting upon his own uselessness and the poor part he had played at the time of his country's need; and now it came to him as in a flash that this was the appointed hour. That he would lose his own life in the endeavour to give these men up to France he was quite convinced; but this contemplation of sacrifice pleased him, and there was but one regret--that he could do nothing which would not wound the father of her he had so greatly loved. Yes, if he could call Frenchmen to this hiding-place they would spare none, and Ludenmayer would perish with the others. Sadi said that many a daughter mourned a father in Strasburg that day--why should little Lucy be spared? And yet he could not bring himself to harm his old friend. Did he not owe his life to him? It was a strange scene--the big cellar lighted by guttering candles, the red fire flickering upon the hearth, and the sombre figures of the burly Prussians lolling over their dishes or their pipes. From time to time one or other would quit the place stealthily, returning anon with news from the ramparts or the streets. The young lieutenant disappeared altogether toward midnight, and Sadi knew that he had re-crossed the lines while his friends were pledging him in giant bumpers of champagne. As the hours went on the hilarity became reckless and, as it seemed to Sadi, even dangerous. Ludenmayer called for silence more than once, but the men, warmed with the wine, obeyed him reluctantly, and were soon talking and laughing again. It was at the height of such an outburst that Sadi touched his friend upon the shoulder and bethought him of the very first lie he had told in all his life. "Did you say good-bye to the Herr Lieutenant?" he asked, in a low voice; and then continued, "I hope so, for you will never see him again, friend Ludenmayer." The captain, who had been squatting upon a heap of straw by Sadi's side, laughed a little incredulously, but his nervousness was evident when he asked:-- "And why should we not see him again, Sadi?" "Because they know where he will recross to-night." "They know! Who knows, then?" [Illustration: "I CAME HERE TO WARN YOU."] "Levoire and the staff. It is rumoured that you are hiding in the ruins. I came here to warn you--you alone, mind, not the others." He raised a finger as much as to say, "This is the compact between us." The Prussians round about were playing cards and dominoes, and quarrelling over their games. Ludenmayer, fallen serious in a moment, seemed to be turning over Sadi's words in his mind. Presently he said:-- "Levoire was a friend of yours, I think?" "I had the honour to be instructor to his wife." "Then she was your informant?" He had put the idea into Sadi's head, and the fiddler seized upon it with avidity.