in the bass. The harmonisation is similar to that in Bach's Leipzig cantatas, with the keys shifting between major and minor.BWV 676 Allein Gott in der Höh' (All glory be to God on high) BWV 676 is a trio sonata for two keyboards and pedal, 126 bars long. The melody of the hymn is omnipresent in the cantus firmus, the paraphrase in the subject of the upper parts and in the harmony. The compositional style and detail—charming and galant—are similar to those of the trio sonatas for organ BWV 525–530. The chorale prelude is easy on the ear, belying its technical difficulty. It departs from the trio sonatas in having a ritornello form dictated by the lines of the cantus firmus, which in this case uses an earlier variant with the last line identical to the second. This feature and the length of the lines themselves account for the unusual length of BWV 676. The musical form of BWV 676 can be analysed as follows: bars 1–33: exposition, with left hand following right and the first two lines of the cantus firmus in the left hand in bars 12 and 28. bars 33–66: repeat of exposition, with right hand and left hand interchanged bars 66–78: episode with syncopated sonata-like figures bars 78–92: third and fourth lines of cantus firmus in canon between the pedal and each of the two hands, with a countertheme derived from trio subject in the other hand bars 92–99: episode similar to passage in first exposition bars 100–139: last line of cantus firmus in the left hand, then the right hand, the pedal and finally the right hand, before the final pedal point, over which the trio theme returns in the right hand against scale-like figures in the left hand, creating a somewhat inconclusive ending:BWV 677 Allein Gott in der Höh' (All glory be to God on high) BWV 677 is a double fughetta, 20 bars long. In the first five bars the first subject, based on the first line of the cantus firmus, and countersubject are heard in stretto, with a response in bars 5 to 7. The originality of the complex musical texture is created by pervasive but unobtrusive references to the cantus firmus and the smooth semiquaver motif from the first half of bar 3, which recurs throughout the piece and contrasts with the detached quavers of the first subject. The contrasting second