I'm making a ships stove. It's a fun little side trip. Lots of pictures on the net. One thing I'm wondering about. They have a chain drive rotisserie that gets it's power from the stove's flue. Does anyone know what's in the flue? A fan of some kind? My mind can't wrap it's self around there being enough flow in the flue to power it. Especially with the 1:1 gearing and clunky chain drive that it has. I'm pretty sure I could never get anything like that to work. A totally unimportant question but curious