Her _debut_ took place at a concert at Devonshire-house, in the Easter week. Such was her reputation, not only for musical genius, but for beauty, elegance, and fascination of every kind, that the crowds of eager spectators in the streets equalled the throng of nobility, rank, and fashion under the roof of the great _dilettante_ and patron of art, the Duke of Devonshire. A few days afterwards, she made her first appearance at her Majesty's Theatre, when she more than realized the high expectations which had been raised. Most of the great _prime donne_ of our times have been compelled, in soprano parts, to compensate by their genius and science for the want of compass in their voices--as, for example, in the case of Pasta, whose natural voice was a rugged mezzo-soprano; and of Malibran, who was a real contralto. In Madame Sontag, the public found a real soprano, "to the manner born," enabling her to perform with certainty of tone, and with exquisite ease, purity, and delicacy, the most intricate passages and original embellishments, whether in full tone or _mezzo voce_. When she first appeared in _Rosina_, she revelled and luxuriated in roulades, arpeggios, and fanciful divisions; and, subsequently, in _Donna Anna_, she proved that she could sing in the chastest classical style, and produce the same effect by pure sentiment and expression, as she had done before by fioriture and staccato passages. Any further account of the performances of Madlle. Sontag at this period would be supererogatory, that portion of her career being known to our readers either from personal observation or from report. She found herself again with Malibran, and we quote the following anecdote to give another proof of the good understanding which prevailed between Madame de Rossi and Malibran. One day Malibran accidentally met the great tenor, Donzelli, and from his countenance she guessed he was in huge dudgeon at some theatrical affair. "What is the matter with you?" said Malibran. "It is near the end of the season," answered the great tenor, "and I have not been able to fix on an attractive opera for my benefit." "Have you thought of nothing?" "Yes." "Well, what is it?" "I had thought of the _Matrimonio_, but Pisaroni says she is quite ugly enough without playing Fidalma; and then you would not be included in the cast, and I don't know what opera to choose in which you would not have the second part to Madlle. Sontag's first--that would not please you, and I'm in despair." "Well," said Malibran, "to please you, and to show you I would play any part with dear Sontag, I'll play Fidalma." "What, old Fidalma? You are joking!" "No, I'm not; and to prove that I'm in earnest, announce it this very day." Donzelli, scarce believing his own good luck, announced the opera. Malibran, dressed in most exquisite caricature, was admirable in this part, and to her we owe the subsequent appearance of great _prime donne_ in the part. The only performer