Johannes Maelzel was known as the inventor of the Maelzel Metronome-or M.M., as it is still abbreviated in sheet music. Beethoven knew Maelzel personally and helped to popularize his musical gizmo. Another Maelzel invention, which failed to catch on, was the Panharmonicon. "Wellington's Victory" was commissioned and composed for this instrument, although it is best known today in Beethoven's orchestral arrangement. The Panharmonicon was sort of like a barrel organ, but more complex. It was capable of imitating all of the orchestral instruments, but could also apparently imitate heavy artillery. Although posterity has not always been kind to "Wellington's Victory," Beethoven himself was quite fond of it. In fact, he rearranged it several times, which made "Wellington's Victory" one of his most financially successful works.