Maria Theresa, and is extolled by Burney--who speaks of her
"marvelous accuracy" in the writing of English--as a singer and a
player, almost as highly as Gluck's niece. Her name finds a place
in the biographies of Mozart, who, at her musical receptions,
used to take part with her in duets of her own composition.
Several of her manuscripts are still in the possession of the
Gesellschaft der Musikfreunde. Something of her musical
distinction ought certainly to be attributed to Haydn, who gave
her daily lessons for three years, during which time he was
comfortably housed with the family.

Porpora

It was through Metastasio, too, that he was introduced to Niccolo
Porpora, the famous singing-master who taught the great
Farinelli, and whose name is sufficiently familiar from its
connection with an undertaking set on foot by Handel's enemies in
London. Porpora seems at this time to have ruled Vienna as a sort
of musical director and privileged censor, to have been, in fact,
what Rossini was for many years in Paris. He was giving lessons
to the mistress of Correr, the Venetian ambassador--a "rare
musical enthusiast"--and he employed Haydn to act as accompanist
during the lessons.

Menial Duties

We get a curious insight into the social conditions of the
musicians of this time in the bearing of Haydn towards Porpora
and his pupil. That Haydn should become the instructor of
Fraulein Martinez in no way compromised his dignity; nor can any