CHAPTER XVIII. IRREGULAR FORMS.

CAUSES.--Despite the many points of resemblance between the various forms to which our successive chapters have been devoted,--the natural consequence of a continuous line of structural evolution to which each plan owes its origin,--they are separate and independent designs, with individual character and purpose; so much so, that the composer may, and usually does, select and apply his form according to the purpose which he has in view. But the form is made for the music, not the music for the form; no serious composer writes music for the sake of the form, but chooses the form merely as a means to an end. The highest ideal of structural dignity and fitness is, to work from the thematic germ _outward_, and to let the development of this germ, _the musical contents_, determine and justify the structural plan and arrangement.

But the aims of the composer outnumber the regular forms, and therefore modifications are unavoidable, in order to preserve the latitude which perfect freedom of expression demands. The student may rest assured of the existence of many irregular species of these fundamental forms (as exceptions to the rule) and must expect to encounter no little difficulty and uncertainty in defining the class to which his example belongs,--until wider experience shall have made him expert.

All such irregular (or, in a sense, intermediate) varieties of form must necessarily either admit of demonstration as modification of the regular designs; or they will evade demonstration altogether, as lacking those elements of logical coherence which constitute the vital and only condition of "form and order" in musical composition.

To these latter comparatively "_formless_" designs belong:--all the group-forms; the majority of fantasias, the potpourri, and, as a rule, all so-called tone-poems, and descriptive (program) music generally.

On the other hand, those irregular designs which nevertheless admit of analysis according to the fundamental principles of structural logic, and are therefore directly referable to one or another of the regular forms, may be classified in the following four-fold manner--as Augmentation, Abbreviation, Dislocation, or Mixture, of the proximate fundamental design.

1. AUGMENTATION OF THE REGULAR FORM.--To this species belong those forms (small and large) which are provided with a separate Introduction, or Interludes, or an _independent_ Coda (in addition to, or instead of, the usual consistent coda).

For example, Beethoven, pianoforte sonata, op. 13, first movement; the first ten measures (_Grave_) are a wholly independent Introduction, in phrase-group form, with no other relation to the following than that of key, and no connection with the fundamental design excepting that of an extra, superfluous, member. The principal theme of the movement (which is a sonata-allegro) begins with the _Allegro di molto_, in the 11th measure. Similar superfluous sections, derived from this Introduction, reappear as Interlude between the Reposition and Development, and near the end, as independent sections of the coda.

In a manner closely analogous to that just seen, the fundamental design of any movement in a _concerto_ is usually expanded by the addition of periodically recurring sections, called the "_tutti_-passages," and by a "_cadenza_," occurring generally within the regular coda. In some concerto-allegros (for instance, in the classic forms of Mozart, Beethoven and others), the first orchestral _tutti_ is a complete _introductory_ Exposition, in concise form, of the thematic material used in the body of the movement. See the first piano-forte concerto of Beethoven, first movement.

Further, when the design is one of unusual breadth, as in some symphonic movements, or in elaborate chamber music, the number of fundamental thematic members may be so multiplied that it is necessary to assume the presence of _two successive Subordinate themes_, of equal independent significance,--such significance that neither of them could be confounded with a mere codetta, or any other inferior thematic member. See Beethoven, pianoforte sonata, op. 7, first movement; the Subordinate theme runs from measure 41 to 59; it is followed by another thematic section (60-93) which is so independent, important and lengthy, that it evidently ranks coordinate with the former, as _second Subordinate theme_. It might, it is true, be called the second Part of the Subordinate theme (the latter being no more than a repeated period); or it might be regarded as the first codetta; its thematic independence seems, however, to stamp it Second Subordinate theme.

Further, it is not uncommon to extend the sonatine-form by adding, at the end, a more or less complete recurrence of the Principal theme,--instead of, or dissolved into, the customary coda. This may be seen in Mozart, pianoforte sonata, No. 3, _Andantino_; the superfluous recurrence of the Principal theme begins in measure 19 from the end, after the regular sonatine-design has been achieved, fully, though concisely.

2. ABBREVIATION OF THE REGULAR FORM.--This consists chiefly in the omission of the Principal theme after the Development (that is, in beginning the Recapitulation with the Subordinate theme). Other contractions, by omission of _portions_ (Parts) of important thematic members, during the Recapitulation, are also possible, but not so common.

An illustration of the omitted Principal theme may be found in Mendelssohn, Songs Without Words, No. 5:--

_Principal Theme_, period, extended (measures 1-11, dissolved into Transition--18).

_Subordinate Theme_, phrase, repeated and extended (19-28). _Codetta_ (28-33). _Double-bar_.

_Development_ (measures 34-58). _Retransition_ (59-62).

_Principal Theme_--omitted.

_Subordinate Theme_, as before (63-76). _Codetta_.

3. DISLOCATION OF THEMATIC MEMBERS.--By this is meant, any exchange or alteration of the regular and expected arrangement of members. This can refer, naturally, only to what occurs _after the Exposition_,--that is, during the Recapitulation; for it is the Exposition which determines the plan, and regular order, of the thematic members. For example, Mozart, pianoforte sonata. No. 13, first movement:--

_Principal Theme_, with _Transition_ (measures 1-27).

_Subordinate Theme_ (28-41).

_Codetta I_ (42-53).

_Codetta II_ (54-58). In the Recapitulation, the arrangement is thus:--

_Principal Theme, Codetta I, Subordinate Theme, Codetta II_; that is, the first codetta appears before, instead of after, the Subordinate theme.

4. MIXTURE OF CHARACTERISTIC TRAITS.--This process tends to affiliate the two distinct classes of larger or higher forms, whose respective characteristics were explained and compared at the beginning of Chapter XVI. Upon very careful revision of this explanation, and reference to the given diagrams, the student will perceive that the distinctive trait of the sonata-allegro form is the section of Development which it contains; and that of the three Rondo-forms is the absence of such a Development. Of the mixed forms under consideration there are two: one in which a section of _Development_ is introduced into the Rondo (as substitute for one of its Subordinate themes); and the other a sonata-allegro, in which the Development is omitted, and a new theme (a sort of additional Subordinate theme) inserted in its place. In other words, a Rondo (second or third form--probably _not_ the first rondo-form) with a Development; and a sonata-allegro with a new Middle theme, or Episode (as we have already called it).

The Rondo with Development is illustrated in Beethoven, pianoforte sonata, op. 27, No. 1, last movement; it is the third rondo-form, designed as follows:--

_Principal Theme_, Two-Part form (measures 1-24).

_Transition_ (25-35).

_First Subordinate Theme_, period, extended,--or phrase-group (36-56). _Codetta_ (57-72).

_Re-transition_ (73-81).

_Principal Theme_ (82-97).

_Transition_ (98-106). Then, instead of the Second Subordinate theme, a

_Development_ (106-138); followed by an elaborate

_Re-transition_ (139-166), and a regular

_Recapitulation_. Two wholly independent coda-sections are added, an _Adagio_ (derived from the third movement of the sonata) and a _Presto_, based upon the Principal theme.

The sonata-allegro with new Middle theme is illustrated in Beethoven, pianoforte sonata, op. 14, No. 1, first movement; the middle Division contains a preliminary allusion to the Principal theme, but is otherwise an entirely new thematic member, very suggestive of the "Second Subordinate theme" of the Rondos (17-measures long,--up to the Re-transition, in which, again, the Principal theme is utilized).

LESSON 18.--Analyze the following examples of Irregular form. They are classified, as in the text:--

1. Beethoven, sonata, op. 81, first movement.

Beethoven, sonata, op. 49, No. 2, first movement.

Beethoven, sonata, op. 2, No. 3, first movement.

Beethoven, sonata, op. 49, No. 1, last movement (_not_ "Rondo," as marked, but sonatine-form, augmented).

Mozart, sonata No. 1, first movement.

Mozart, sonata No. 17, last movement (Rondo, with three Subordinate themes).

Mendelssohn, _Capriccio brillant_, in B minor. Schubert, pianoforte sonata No. 8 (Peters ed.). _Adagio_.

2. Mendelssohn, _Praeludium_, op. 35, No. 3.

Mozart, sonata No. 8, last movement.

Schubert, sonata No. 8, last movement.

Brahms, pianoforte _Capriccio_, op. 116, No. 1.

Chopin, pianoforte sonata, op. 35, first movement.

3. Mozart, sonata No. 3, first movement.

Mozart, sonata No. 13, last movement (the Development occurs _after_ instead of before the Principal theme,--in the Recapitulation).

4. Beethoven, pianoforte sonata, op. 31, No. 1, last movement.

Beethoven, pianoforte sonata, op. 90, last movement.

Mendelssohn, pianoforte étude, op. 104, No. 2.

Beethoven, pianoforte sonata, op. 10, No. 1, first movement.

Beethoven, pianoforte sonata, op. 2, No. 1, last movement.

Mozart, sonata No. 7, _Andante_.

Mozart, sonata No. 14, last movement.