We have already remarked how most of Bach’s fugues, especially the shorter ones, can be divided into three sections based upon harmony. In the preludes to the English suites the question of musical material enters into the division. Take for analysis the prelude in A minor to the second suite. The first section ends at the beginning of the fifty-fifth measure. It will be seen to open with a bold figure, the first notes of which are at once imitated in the left-hand part. There follows then a constant flow of figure work over a relatively simple harmonic foundation and through orderly sequences, the hands frequently imitating each other. Fragments of the opening phrase are heard five times. In the thirty-first measure a very distinct phrase is introduced, still in the tonic key, it will be observed, though in dominant harmony; and this is repeated in purely conventional manner in three registers, giving way to formal passage work which, falling and rising, leads to a good stout reiteration of the opening motive. With this the first section ends, in a full tonic cadence.
The second section begins at once with a wholly new figure which dominates the music from now on up to the one hundred and tenth measure. At this measure the second section ends, and here Bach might have written the words da capo; for what follows is but a repetition of the first fifty-five measures.
It must be noticed that, although the middle section is decidedly dominated by a figure which does not appear in the first, still the first theme is not allowed to be forgotten. It may be found five times in the course of the middle section, dividing, as it were, the new material into distinct clauses, and serving as well to impress upon our ears the unity of the piece as a whole.
This device is not truly germane to the aria form. It is suggestive of the rondo in general; and in particular of the modified rondo form of the Vivaldi violin concerto, of which we know Bach made a minute study.
In the splendid prelude to the third suite, in G minor, this concerto form is far more in evidence than the aria form. But the fourth, fifth, and sixth (barring the slow introduction) are like the second in superbly simple three-part aria form. This fact is well worth recollecting in connection with the development of the sonata form of a later period.
The remaining movements of the suites present no irregularities. These are the dignified allemandes, the Italian or French courantes, the elusive, sad sarabandes, always one or two Intermezzi, a Gavotte, a Bourrée, a Passepied or a Minuet, and the final Gigues with their conventional contrapuntal tricks and turns.
The Partitas are far less regular in structure. The opening movements are called by various names. There is a prelude for the first, short and in simple, rich style; a Sinfonie for the second, with three distinct parts, suggesting the French overture; a Fantasie for the third; and for the fourth, fifth, and sixth, respectively, an Overture, a Preamble, and a Toccata. The second and third have odd movements, such as a Rondo, a Caprice, a Burlesca, and a Scherzo. On the whole, in spite of the technical perfection never absent in Bach’s work, and some movements such as the closing Gigue of the first partita, these suites are inferior to the English suites. There is something tentative about the new styles of preludes and about the interpolation of freakish intermezzi, which rather mars them from the point of view of unity and balance in the cyclic forms.
But the English suites stand out as magnificent specimens of vigorous and yet emotional music, great and broad in scope, perfect in detail—keyboard music which in many ways has never been surpassed.
VII
Besides the fugues and the suites there is a great deal of other and less easily defined harpsichord and clavichord music. We are not wanting in titles. We have Preludes, Toccatas, and Fantasias, also some Capriccios. These are, on the whole, of free and more or less whimsical structure. The preludes, and one thinks of the forty-eight little masterpieces of the ‘Well-tempered Clavichord,’ are usually simple and short. They are for the most part clearly harmonic music. Some are nothing more than a series of chords, notably those in C major, C minor, D minor, in the first part. The origin of this simple form of music has already been discussed; but the origin of the particular and well-nigh matchless beauty of these of Bach’s preludes can be found only in the great depths of his own genius, which here more almost than anywhere else, is incomprehensible. The subtlety of the modulations, the great tenderness and poetry of the chords, the infinite suggestion of feeling—all these within little pieces that might easily be printed on half a page, that have no definite outline, no trace of melody: we can but close our eyes and wonder.