Nevertheless, the amorous Marquis, who might have relied upon the solemn promise of his mistress, had it not been for the intense fears which were ever present in his mind, and becoming more violent as the hour for his departure drew nearer, required something more substantial than words. But what could he exact? Ah! an idea, a novel expedient occurred to his mind, one which he imagined would restrain the most obstinate inconstancy. "Listen, Ninon, you are without contradiction a remarkable woman. If you once do a thing you will stand to it. What will tend to quiet my mind and remove my fears, ought to be your duty to accept, because my happiness is involved and that is more to you than love; it is your own philosophy, Ninon. Now, I wish you to put in writing that you will remain faithful to me, and maintain the most inviolable fidelity. I will dictate it in the strongest form and in the most sacred terms known to human promises. I will not leave you until I have obtained such a pledge of your constancy, which is necessary to relieve my anxiety, and essential to my repose." Ninon vainly argued that this would be something too strange and novel, foolish, in fact, the Marquis was obstinate and finally overcame her remonstrances. She wrote and signed a written pledge such as no woman had ever executed, and fortified with this pledge, the Marquis hastened to respond to the call of duty. Two days had scarcely elapsed before Ninon was besieged by one of the most dangerous men of her acquaintance. Skilled in the art of love, he had often pressed his suit, but Ninon had other engagements and would not listen to him. But now, his rival being out of the field, he resumed his entreaties and increased his ardor. He was a man to inspire love, but Ninon resisted, though his pleading touched her heart. Her eyes at last betrayed her love and she was vanquished before she realized the outcome of the struggle. What was the astonishment of the conqueror, who was enjoying the fruits of his victory, to hear Ninon exclaim in a breathless voice, repeating it three times: "Ah! Ah! le bon billet qu'a la Châtre!" (Oh, the fine bond that la Châtre has.) Pressed for an explanation of the enigma, Ninon told him the whole story, which was too good to keep secret, and soon the "billet de la Châtre" became, in the mouth of everybody, a saying applied to things upon which it is not wise to rely. Voltaire, to preserve so charming an incident, has embalmed it in his comedy of la Prude, act I, scene III. Ninon merely followed the rule established by Madame de Sévigné: "Les femmes ont permission d'être faibles, et elles se servent sans scrupule de ce privilège." CHAPTER IX Ninon's Friendships