Mozart did not compose any larger original works for organ, but he did write three remarkable pieces for musical clock, a mechanical musical instrument with organ pipes which was extremely popular in his day. These unusual works in this genre are the Fantasias K. 594 and K. 608. With these important compositions we are dealing with true masterpieces of a "solemn" character and densely-worked musical structure – just as if Mozart had a real organ in mind from the very beginning.

A completely d...