Patty Smith (I think?) was asking me about this. She suggested a sunday school session about the organ.
Who are the two people named on the plaque on the organ?
A bit about the organ: pipes, manuals, pedals, stops, yadda yadda… and here's what it all sounds like…
Stop list 
this needs information about the pistons
pictures of the inside, because there's no way I'm taking people up there