The six sonatas of Op. 25, were published in 1791 by Joseph Dale. Op. 25, No.2, has a brilliant opening, soon leading to rapid triplets, a continuing feature of the movement. The second movement rondo has a simple principal theme and includes, in its course, a G minor episode. The lyrical F sharp minor sonata Op. 25, No.5, won particular praise, its slow movement the inspiration for a poem by the late nineteenth century Vicenza poet Antonio Fogazzaro. The last movement includes passages in thirds, a technique for which Clementi was particularly well known both as performer and composer. The Sonatina in D major, Op. 37, No.2, variously numbered, appeared as one of a set of three. It remains thoroughly characteristic of Clementi’s earlier work.

The six Progressive Pianoforte Sonatinas were written in 1797 and revised in 1820. The first of the set, in C major, offers an ingenuous first subject, followed by a brief modulation to the dominant and a development of similar length. There is an F major slow movement and a final lively return to the original key. The second sonatina of the group, in G major, provides the player with a marginally greater challenge, leading to a second movement in dotted rhythm and a final movement in 3/8 metre. The third sonatina, in C major, opens with a first subject formed from the descending arpeggio, the development opening with the same figure inverted. The G major movement, in two parts only, cans for cantabile playing and leads to a final C major Allegro. The following sonatina, in F major, includes a B flat major slow movement and a final energetic rondo with triplet rhythms. This is followed by the fifth sonatina, in G major, in which the running triplets of the first movement are succeeded by a Swiss air and a closing rondo of dynamic contrast. Opus 36 ends with a further D Major sonatina, with an opening over an Alberti bass and a second movement that makes characteristic use of thirds.

The Sonata in B flat Major, Op. 24 No.2, was published in 1788-9 in Mozart’s friend Stephen Storace’s Collection of Original Harpsichord Music. It was revised and re-issued as Op. 41 No.2 in 1804. It was suggested that Mozart remembered the sonata from the Vienna court performance of 1782, when he came to write the Overture to The Magic Flute in 1791. Any thematic resemblance is probably coincidental, although the modem listener cannot but be aware of the similarity of the first subject.