In Bach's six sonatas of 1742 the movements are detached. But the opening movement (an Andante in sonata form) of the 2nd Sonata of the Leipzig Collection of 1779 ends with a few bars in canonic form (and with quaint Bebung effect), leading without break to the following Larghetto. The next sonata also connects the second with the third movement. In the above case the change was merely from the key of tonic major to that of minor; but here the movement is in G minor, and an enharmonic modulation leads to the dominant of B minor, key of the final movement. The sonata begins in B minor, and the choice of the remote key of G minor for the middle movement is somewhat curious. Sonata No. 4 connects first and second movements; and the third is evidently meant to follow without pause. It must, however be remembered that the majority of the Leipzig sonatas do not have the various movements thus connected. It therefore seems to have been an experiment rather than a settled plan. Examples of the connection of movements are also to be found in Nichelmann and J.C.F. Bach. The same thing may be seen in some of Haydn's sonatas (Nos. 18, 22, etc.), while Beethoven offers a remarkable instance in his sonata, Op. 57. The 1st Sonata of the 2nd Collection passes from the first to the second movement (Allegretto, G minor; Larghetto, F sharp minor) in a curious manner, by enharmonic means. The last bar has-- [Music illustration] The quotation is in abbreviated form. The second chord would, of course, be taken at first as dominant minor ninth on G. The 1st Sonata of the 4th Collection is not striking as music, and certainly not of sufficient importance to justify serious inquiry into the peculiar order of keys for the three movements (G, G minor, and E major). With regard to the number of movements, all except two of the eighteen sonatas have three; the second and third of the 2nd Collection have only two. John Christian Bach, or the "London" Bach, as he was called, dedicated his fifth work, consisting of six sonatas "Pour le clavecin ou pianoforte," to Ernst, Duke of Mecklenburg. This cannot have been before 1759, as that was the year in which the composer came to London. He describes himself on the title-page as--"Maitre de Musique de S.M. la Reine d'Angleterre." These sonatas, as we learn from the dedication, were written for the "amusement" of the Duke. The first, third, and fourth have each only two movements. They remind us less of E. Bach than of Haydn's early style. There is some very fresh, pleasing writing in them. No. 5 has some excellent practising passages, and perhaps the following-- [Music illustration] may have suggested to Cramer his first study. The middle movement of No. 6 is a vigorous double Fugue; the whole sonata is, indeed, one of the finest of the set.