Chapter XXV: Section 5: (107-115), establishment of the dominant. Section 6

(115-124), the _Re-transition_. The _Recapitulation_ begins with the

_Principal Theme_, Part I, period (125-132). Part II, group of phrases, longer than before (133-152).

_Subordinate Theme_, as before, but in the principal key (153-174).

_Codetta (I)_, as before, but slightly extended (175-187). The second codetta is omitted.

_Coda_, phrase, repeated and extended (188-200).

RELATION TO THE THREE-PART SONG-FORM.--In a former chapter (XIII) the Three-Part form was defined as the type of perfect structural design, upon which every larger (or higher) form is based. Nowhere is the connection more striking, and the process of natural evolution out of this germ more directly apparent, than in the sonata-allegro design. See the diagram on page 124. The Exposition corresponds to the First Part, _so expanded as to comprise 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, according to the general plan adopted in our text:--

Beethoven, pianoforte sonatas; op. 2, No. 1, first movement (diminutive, but very complete and perfect).

Op. 2, No. 2, first movement.

Op. 10, No. 3, _Largo_.

Op. 22, first movement (four or five codettas).

Op. 14, No. 1, first movement.

Op. 22. _Adagio_.

Op. 27, No. 2, last movement.

Op. 28, first movement.

Op. 31, No. 1, first movement.

Op. 31, No. 3, first movement (the last 2 1/2 measures of the Exposition are a transitional Interlude, which leads back into the repetition, and on into the Development).

Same sonata, _Scherzo_.

Op. 31, No. 2, last movement (coda contains the entire principal theme).

Op. 78, first movement (diminutive).

Op. 79, first movement.

Op. 90, first movement, (no "double-bar").

Op. 57, first movement.

Same sonata, last movement.

Mozart, sonatas: No. 7, first movement.

No. 3, first movement. No. 4, first movement; also _Andante_.

No. 8, first movement. No. 5, first movement.

No. 10, first movement. No. 6, first movement.

No. 1, _Andante_. No. 6, last movement.

Mendelssohn, pianoforte _Caprice_, op. 33, No. 2 (brief introduction).

Sonata, op. 6, first movement.

Op. 7, No. 7.

_Fantasia_, op. 28, last movement.

Schubert, pianoforte sonatas: op. 143, first movement.

Op. 42, first movement.

Op. 120, first movement.

Op. 147, first movement (in the Recapitulation, the principal theme is transposed).

Op. 164, first movement (the same).

Beethoven, symphony, No. 5, first movement.

Symphony, No. 1, first _Allegro_; also the second movement; and the _Finale_.