Before Movies Had Sound, There Was the Mighty Wurlitzer
CNET has this look back to the days when silent movies were made less silent by someone playing a big-ass organ.
The instrument is a beauty. It has four keyboards and 1,600 pipes as well as some key-operated instruments (cymbals, castanets, drums) in order to provide the right type of sounds for playing background for a silent movie.
It also can play sound effects like car horns, bells, and whistles. It relies on the talent of the player to master such a device.