My brother sent me a link to this...
This is a water-powered line-shaft mill. The video starts with a bit of iron/forge work, but the balance of it (Starting around the 5 minute mark) shows the guy building a stock watering trough from start to finish. He planes the wood, joints the wood, makes dowels, cuts dados and angles, and everything on ancient water-powered tools.
Fun and interesting to watch a slice of history.
(Not fine woodworking, but fine nonetheless!)