nd subject is in A minor.

In major keys, besides that of the dominant, Beethoven chose the
mediant (E) in his sonata in C (Op. 53); and in the recapitulation it
occurs first in the sub-mediant (A), and only afterwards, in varied
form, in the orthodox tonic. Then in the B flat sonata (Op. 106) the
second subject occurs in the sub-mediant (G). In the last sonata in C
minor, the second subject is neither in the relative major, nor in the
dominant minor, but in the major key of the sub-mediant. Once again,
in the sonata in D major (Op. 10, No. 3) a second theme is introduced
in the key of the relative minor before the dominant section is
reached. With regard, indeed, to the number of themes and order of
keys, some other movements of the Beethoven sonatas show departures
from the orthodox rules.

In the important matter of the repeat of the first section of a
movement in sonata-form, we find the master, for the most part,
adhering to the custom delivered unto him by his predecessors. And yet
there were two strong reasons why he might have been tempted to depart
from it. The repetition was a survival from the old dance movements in
binary form. E. Bach, Haydn, and Mozart not only repeated, but
introduced various kinds of ornaments, and even harmonic changes; and
they expected performers to do the same. Beethoven, however, allowed
no such licence--one, indeed, which in the hands of ordinary pianists
would be calculated to spoil rather than to improve the music. Part,
then, of the _raison d'etre_ of the repeat ceased to exist. But a
still stronger temptation to suppress it must have been the
_programme_ or _picture_ which Beethoven had in his mind when he
composed. The repeat, now become almost an empty form, must have
proved at times a fetter to his imagination. In many ways he was bold;
but in this matter strangely conservative. It was only in the sonata
in F minor, Op. 57, that he first ventured to omit the repeat. It is
not to be found in the opening movements of Op. 90 or Op. 110, yet in
his last sonata (Op. 111) the composer almost seems as if he wished to
atone for his previous sins of omission. He had evidently not settled
the question one way or the other; but the fact that in three of his
most poetical works he departed from custom, deserves note. Before his
time the repeat, like the laws of the Medes and Persians, seemed
irrevocably fixed.

Beethoven added important introductions or codas, or even both, to
some