Two clavier pieces of indeterminate affiliation. Mentioned in K. Appendix 20a (K.6: 626b/25). 1. Clavier piece in B flat

The many individual pieces for keyboard instruments (including the few works for glass harmonica and mechanical instruments) belong to a variety of traditions. By far the largest group—nearly 60 individual works—dates from Mozart’s childhood. Leopold Mozart entered a large number of pieces into the notebook he originally created for his daughter Maria Anna’s piano lessons; these include the very first works by Mozart. Wolfgang was not able to write down his own compositions until the age of eight. During a serious illness of his father in England, Mozart filled the so-called London Notebook with 42 keyboard pieces (K. 15a–K. 15ss) in 1764. Some of Mozart’s later keyboard pieces are written-out fantasias, and there is also a series of rondo movements, especially from his Viennese period. In this context, the piano reductions of ensemble dances are also worth mentioning. In the final years of his life, Mozart was commissioned several times to write music for elaborate mechanical organs in the so-called Müller Art Cabinet (K. 594, K. 608, and K. 616). These works soon became known after Mozart’s death through piano arrangements, mostly for piano four hands.