omprise the two themes and codetta_, fused
into one larger division; the "statement" of a more comprehensive
thematic group than the ordinary Part contains, but no more, for all
that, than the usual initial "statement." The Development corresponds
to the Second Part (proportionately expanded), and the Recapitulation
to the Third Part, or recurrence and confirmation of the "statement."

Any Three-Part Song-form, the moment that its First Part expands and
divides into the semblance of two fairly distinct thematic sections,
becomes what might be called a miniature sonata-allegro form. Many
Three-Part Song-forms are so broad, and many sonata-allegros so
diminutive, that it is here again often difficult to determine the line
of demarcation between them. Example 55 (cited because of its
comparative brevity) is scarcely more than such a broadly expanded
Three-Part Song-form. An example which approaches much more nearly the
unmistakable Three-Part song, may be found in Mozart, sonata No. 12,
_Menuetto_:--

_Part I_, section one (embryo of a principal theme), measures 1-10,
period, extended; section two (embryo of a subordinate theme) measures
11-18, period, _in different key_.

_Part II_, group of three phrases, measures 19-30.

_Part III_, section one, as before, measures 31-40; section two, as
before, _but in the principal key_, measures 41-48.

This is, of course, a Three-Part Song-form; but the essential features
of the Sonata-allegro are unquestionably present, in miniature.

See also, Beethoven, sonata, op. 101, first movement; certainly a
sonata-allegro design, but diminutive.

* * * * * *

The superiority of the sonata-allegro form over all other musical
designs, is amply vindicated by the breadth of its thematic basis, the
straightforwardness and continuity of its structural purpose, the
perfection of its thematic arrangement, and the unexcelled provision
which it affords for unity, contrast, corroboration, balance, and
whatever else a thoroughly satisfactory structural design seems to
demand. Hence, while brief triumphs of apparent "originality" may be
achieved by simply running counter to this and similar designs, it
seems scarcely possible that any musical form could be contrived that
would surpass the sonata-allegro, the last and highest of the forms of
composition.

LESSON 17.--Analyze the following examples, as usual, carefully
defining all the details of the form,