The middle movements of Nos. 2, 3, 5, and 6 are in the key of the relative minor; that of No. 1 is in the tonic minor, and that of No. 4 (C minor), in the relative major.  No. 1, twice interrupted by a recitative (upper part and figured bass),[64] is dignified, yet tender, and, in form, original.  The Adagio, in C sharp minor, of No. 3 is a movement of singular charm; it is based on imitation, but, though old in style, it breathes something of the new spirit, or rather—­for there is nothing new under the sun—­of the old Florentine spirit which freed music for a time from the fetters of polyphony.  The genius of Johann Sebastian Bach gained the victory over form, and, in fact, exhausted fugue-form.  It is in the clever, but dry fugues of some of his contemporaries and, especially, successors, that one can feel the absolute necessity for a new departure.  This Adagio is, as it were, a delicate remembrance, and one not unmixed with sadness, of the composer’s immortal parent.

The light, lively final movements need no description.  All the music of these sonatas is written in two or three parts or voices; occasionally there are chord passages in which for the moment the number is increased.  We have dwelt somewhat in detail on this work, as it appears to be little known.

There is a sonata in the key of D major, published in the 3rd Collection (1763) of Marpurg’s Clavierstuecke (p. 10), by E. Bach, which was written in the same year (1740), but earlier than the “Frederick” Sonatas.  C.H.  Bitter remarks that if the year of composition were not known, it would certainly pass as a much later work.  The first movement reminds one of Beethoven’s terse, bold style.  Bitter refers to the freedom with which the thoughts are expressed, to the melodious character of the Andante, and to the humour of the Finale.  He might also have referred to the style of writing for the instrument, which suggests a later date.

In 1745 (?) appeared the Wuertemberg Sonatas (so called because they were dedicated to Bach’s pupil, the Duca di Wirtemberg e Teckh, as he is named on the title-page of the original edition).  These sonatas are marked as Opera seconda.  They were offered by the composer to the Duke in recognition of the many favours shown to him “at the time when I had the honour of giving you lessons in music at Berlin."[65] Of these sonatas we have only been able to have access to the two preserved in the British Museum; the others are probably of similar character.

No. 1, in E flat, opens with an Adagio, followed by an Allegro assai (E flat), and then by a Menuet alternato and Trio, both in E flat, and with the former da capo.  The first and second movements are in old binary form; the Allegro shows the influence of D. Scarlatti.  The Minuet is fresh and pleasing.  It is evident, taking E. Bach himself as standard, that this is a suite rather than a sonata.