There is, unfortunately, great confusion in the opus numbers of Dussek's works; and, moreover, it is difficult, if not impossible, to give the dates either of composition or publication. Breitkopf & Haertel have published more than fifty sonatas, but we shall only refer to some of the more important ones. Dussek, like all the prominent composers of his time, not even excepting Haydn and Mozart, wrote music on a practical, rather than on a poetical basis; one of the letters given above acknowledges this in very frank terms. But to Dussek's credit be it said, his least valuable works are masterpieces as compared with those which the sonata-makers, Steibelt, Cramer, and others, fabricated by the hundred. In Dussek we find great charm and refinement, while the writing for the instrument is often highly attractive; but the art of developing themes was certainly not his strong point. That he was at times careless or indifferent may be seen from such a bar as the following (Op. 47, No. 1, Litolff ed.; Adagio, bar 9):-- [Music illustration] The bar before the return of the principal theme in the Allegro of the sonata in E flat (Op. 75) furnishes another instance. Again, in the Allegro of the sonata in A flat, known as "Le Retour a Paris," there is a passage (commencing fifteen bars before the end of the exposition section) which, with slight alteration, might have been materially improved. Of the early sonatas, Op. 10, No. 2, in G minor, is an interesting work. It consists of two well-contrasted movements: an Adagio in binary, and a Vivace in sonata form. Of the Presto of Op. 10, No. 3, Professor Prout, in his interesting article, _Dussek's Pianoforte Sonatas_,[87] says: "Both the first and second principal subjects remind us irresistibly of that composer (Mendelssohn), while the phrase at the conclusion of the first part, repeated at the end of the movement, is almost identical with a well-known passage in the first movement of the 'Scotch Symphony.' Is the coincidence accidental, or did Mendelssohn know the sonata, and was he unconsciously influenced by it?"