How an Organ Works
Follow this link to learn about how an organ works: http://www.die-orgelseite.de/funktionsweise_e.htm
Also visit St John's to see/use the educational organ model fixed on the back of the organ case and look inside the organ at the mechanism via the glass panels on the sides of the case - the inside mechanism and pipes can be illuminated by LEDs. There is also a new exhibition surrounding the organ which details the history and function of the organ and the history of Notting Hill. The church is open daily, 10am - 1pm, and often outside of those hours as well.
The panel below is taken from the new history exhibition which now surrounds the organ, more info about this by clicking here.