Content note : Chapter 25 investigates how Mozart composed. Useful for understanding phrasing, ideas, and structure in his music.

Content note : Joseph Haydn composed special music for musical clocks, and obviously did so in close cooperation with his colleague at the Esterhazy court, the court chaplain and librarian P. Primitivus Niemecz, who became well-known for his skills in building musical automata. Two flute clocks (from 1792 and 1793) bearing Niemeczs signature are extant, two others are attributed to him. A further flute clock, made by Johann Joseph Wiest, was on exhibition until 1804 in Deym's art gallery in Vienna, thus presenting Haydn's music to the public - whereas the Niemecz clocks never left private ownership during Haydn's lifetime. The five instruments have 38 musical pieces on their barrels: 18 original compositions by Haydn or arrangements he made of his own works, the remaining pieces probably provided by Niemecz who was also a musician and a pupil of Haydn.