The volume opens with something unusual: opus 42 is a single work, short and surprisingly easy to play- Haydn described it as ''something small and with only 3 pieces''. The Quartets op. 50, including the so-called Frog Quartet, are dedicated to the Prussian king Friedrich Wilhelm II, who was a talented cellist. Even though the ''solo'' at the beginning of opus 50,1 is meant as joke, there are some good passages for cellists.?