The legacy design is called a trompe, here is a video of how it worked from Ragged Chutes Air plant near Cobalt, Ontario Canada. https://www.youtube.com/watch?v

The legacy design is called a trompe, here is a video of how it worked from Ragged Chutes Air plant near Cobalt, Ontario Canada. https://www.youtube.com/watch?v=UtYLVLkWyGc https://www.youtube.com/watch?v=UtYLVLkWyGc