Also the rapid progressions accompanied by solid chords (Ciacona, p. 11):
finally the sixteenth-notes in triplets (Passacaglio, p. 4).
The idea of joining a fugue to the Passacaglias was also derived from Buxtehude, who united a chaconne and a fugue (ibid., No. V).
All this is only incidental, it is true; and we recognize Bach in the length of the work (293 measures) and especially in the skilful counterpoint of the fugue.
From our point of view, the Passacaglio and the Canzone express the whole philosophy of this second period. Bach attains, in these two works, the highest point which it was then possible for him to reach; he comes into his first maturity in treating, it is true, established forms, through which he acquires the necessary mastership for the exploration of new fields.
From this moment progress is manifest. Take the prelude and fugue in F minor;[97] no more superfluous ornaments in the prelude, and, what is especially noteworthy, it is founded entirely, not yet upon a clearly defined subject, but still upon a figure which affects the whole ensemble, imparting to it added coherency.
Up to this time Bach had not achieved such unity, such directness of meaning; and the rapid, stormy passage at the end is more than a mere brilliant cadence: it bears the musical distinction of adding to the dignity of the peroration by emphasizing the tonality, the threads of which are thus united.
In the two preludes in C minor which bear the title of Fantaisies[98] these characteristics are still more pronounced; it is from a veritable subject that they derive the somewhat elegiac character common to both, as well as certain details and even the general outlines; the one is, nevertheless, somewhat more individual because of the use of two themes. Less varied, the character of the other is more intimate, although more uniform.