Sonata in C major for keyboard four-hands, K. 19d

The Sonata in C major, K. 19d, is a work for piano four-hands once thought to be composed by Wolfgang Amadeus Mozart in 1765 when he was nine years old in England.

Composed in the traditional sonata form, it is one of the very few works thought to be written by Mozart for four-handed play.

Toward the middle section (bar 40), the work drops down in tone to a darker, more ominous version of the main theme, before picking back up to the light C major chord.

The final movement, 181 bars long and in 24 time, begins with a modulating chord phrase that is as much joyful as it is exciting.

An interesting point toward the work's possible authenticity is the fact that the writings for both the right and left hand in the score occasionally collide with one another.