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. [Footnote 97: P. ii, 5. B.-G. xv, p. 104.] 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. [Footnote 98: P. iii, 6. B.-G. xv, p. 129, and P. iv, 12 (_a 5 voci_). Accompanying the latter Fantasia is a fugue of which, unfortunately, only the first twenty-seven measures are extant.] To the three fugues which we have mentioned must undoubtedly be added two others, from a chronological point of view, belonging to preludes of a later date; they are the fugues of the Toccata in _F_ major,[99] and of a prelude in _C_ minor.[100] There is truly a remarkable analogy between these five fugues, both in the character of their themes--no longer agitated in movement, but approaching in a slight degree the melodious seriousness of the chorale--and in their treatment. In each of them the interest increases with the development, and the introduction of an accessory subject toward the middle portion (afterwards related to the principal theme), either as a countersubject or for the purpose of preparing the reëntrance of the principal theme, is common to them all. [Footnote 99: P. iii, 2. B.-G. xv, p. 155.] [Footnote 100: P. ii, 6. B.-G. xv, p. 218.] The Toccata[101] in the Dorian mode and the accompanying fugue are perhaps contemporary; this imposing composition still partakes of that character of studied virtuosity which Bach was destined completely to abandon in his later years. [Footnote 101: P. iii, 3. B.-G. xv, p. 136.