The greater organ-works include nearly 20 extended preludes and
fugues, a few toccatas, a passacaglia, and many chorale-preludes and elaborations.
The chief works for clavier alone are the Das wohltemperirte Clavier (48 preludes and figures, Pt. I., 1722, Pt. II., 1744), 12 suites, many inventions, partite, etc., besides Das musikalische Opfer (1747) and Die Kunst der Fuge (1749), the latter of which requires other instruments in part. To these are to be added about a dozen concertos for one, two, three, and even four claviers with orchestra.
The chamber and orchestral works comprise a multitude of sonatas and concertos, (a) for violin, viola pomposa or 'cello alone, (b) for flute, violin or viola da gamba with clavier, (c) for violin with orchestra, (d) for varied combinations of solo instruments, and (e) several overtures for orchestra.
The vocal works include (a) many secular cantatas, serenatas and complimentary pieces, (b) over 200 motets and cantatas for the Sundays and festivals of the Lutheran Church Year (being about two-thirds of five complete annual cycles of such works), (c) 5 Passions, including the St. Matthew (1729), the St. John (1724), together with similar church oratorios for Christmas (six parts, 1734), for Easter and for Ascension, (d) 2 Magnificats, 5 large masses (that in B minor, 1733-8, being the chief) and several shorter ones.
In two directions these works involved technical procedures that were comparatively novel. The first related to the method of keyboard fingering. Bach threw his influence in favor of employing equally all the fingers instead of mostly the middle three, as had been the tendency, and hence of adopting the curved or curled position for the hand instead of a flat or rigid one. In this he anticipated and guided the practice of the later 18th century, when the question of pianoforte technique became urgent. While he himself seems not to have approved of the pianoforte in the types first presented to his attention, by thus increasing dexterity, as well as by his methods of composition (largely induced by his liking for the delicate clavichord), he contributed to the advance of pianoforte music. The second principle was that of equal temperament in tuning, so that modulation might take place freely in all directions (see sec. 136). So strenuous was Bach for this that wherever possible he insisted upon himself tuning the clavichords or harpsichords that he was to play, and many of his works were almost unplayable otherwise. The Well-Tempered Clavichord was a conspicuous fruit of this conviction. Here, again, he was ahead of his age, although he did not originate the principle itself.
119. The Church Cantata and Oratorio.—Bach's relation to the use of extended vocal works of a more or less dramatic type in Lutheran church worship is so important that it requires treatment by itself. As has been noted, his church cantatas probably amounted to about 300 in all, while his Passions and similar
