Even in the midst of such successes and festivals of art, a black spot shows itself upon the horizon: diplomacy labored secretly to work confusion--its protocols became menacing, and it was suddenly announced that M'lle Sontag was about to quit the stage to devote herself to more serious duties. For a year past she had been secretly married to a Count de Rossi, who was no longer willing to share his happiness with the world. M'lle Sontag took leave of the Parisian public at a performance for the benefit of the poor, which was given at the opera, in January of 1830. Upon her return to Berlin, her friends and numerous admirers won her consent to give a few representations, and she quitted the stage definitively two months before the revolution of July. But before entering upon the new path of life which she had chosen, and before laying aside the brilliant renown which had been so justly acquired, M'lle Sontag went a journey to Russia, giving at Warsaw, Moscow, St. Petersburgh, and afterwards at Hamburg and other principal cities of Germany, concerts equally brilliant and profitable. It was after this journey that, under the name of the Countess de Rossi, following the fortunes of her husband, she passed successively many years at Brussels, the Hague, Frankfort, and Berlin, heard only in those assemblies of the distinguished societies of Europe which the revolution of February has shaken to its very foundations. Mademoiselle Sontag possesses a soprano voice of unusual compass, of great equality, and of a marvellous flexibility. From the middle _Do_ to that in _alt_, this voice has the sweet ring of a silver bell, and never need we fear either a doubtful intonation or an ill-balanced phrase in her wonderful displays of vocalization. This rare flexibility of organ is the result of incessant labor, judiciously directed to the development of the munificent gifts of nature. Until her arrival at Vienna, where she had opportunity to hear the great virtuosos of Italy, M'lle Sontag had been guided only by her own happy instincts, and the tastes, more or less cultivated, of the public before whom she sang. It is to the counsels of Madame Maineville-Fodor, and yet more to the example which the admirable talent of this exquisite singer set daily before her, that M'lle Sontag owes the expanding of those native powers which till then had rested, folded as it were, within their bud. The contest with such rivals as Mad. Pisaroni and Mad. Malibran--those heroic combats which she had to sustain upon the stages of Vienna, Paris, and London--accomplished for her talent that degree of full and satisfying maturity which has made M'lle Sontag one of the most brilliant singers of Europe.