The celebrated Abbé de Châteauneuf, in his "Dialogues on Ancient Music," refers to Mademoiselle de l'Enclos under the name of "Leontium," a name given her by le Maréchal de Saint-Evremond, and in his eulogy upon her character, lays great stress on the genius displayed in her epistolary style. After censuring the affectation to be found in the letters of Balzac and Voiture, the learned Abbé says: "The letters of Leontium, although novel in their form of expression, although replete with philosophy, and sparkling with wit and intelligence contain nothing stilted, or overdrawn. "Inasmuch as the moral to be drawn from them is always seasoned with sprightliness, and the spirit manifested in them, displays the characteristics of a liberal and natural imagination, they differ in nothing from personal conversation with her choice circle of friends. "The impression conveyed to the mind of their readers is, that she is actually conversing with them personally." Mademoiselle de l'Enclos writes about the heart, love, and women. Strange subjects, but no woman ever lived who was better able to do justice to them. In her frame of mind, she could not see men without studying their dispositions, and she knew them thoroughly, her experience extending over a period of seventy-five years of intimate association with men of every stamp, from the Royal prince to the Marquis de Sévigné, the latter wearying her to such an extent that she designated him as "a man beyond definition; with a soul of pulp, a body of wet paper, and a heart of pumpkin fricasseed in snow," his own mother, the renowned Madame de Sévigné, admitting that he was "a heart fool." Ninon took this weak Chevalier in charge and endeavored to make a man of him by exposing his frailties, and, entering into a long correspondence, to instruct him in the pathology of the female heart, with which he was disposed to tamper on the slightest provocation. Her letters will show that she succeeded finally in bringing him to reason, but that in doing so, she was compelled to betray her own sex by exposing the secret motives of women in their relations with men. That she knew women as well as men, can not be disputed, for, beginning with Madame de Maintenon and the Queen of Sweden, Christine, down along the line to the sweet Countess she guards so successfully against the evil designs of the Marquis de Sévigné, including Madame de La Fayette, Madame de Sévigné, Madame de La Sablière, and the most distinguished and prominent society women of France, they all were her particular friends, as well as intimates, and held her in high esteem as their confidante in all affairs of the heart.