How does "Euro Tunnel" make steam engines stop smoking? I know why, so the smoke doesn't waft up magically through the roof and the ground above, but I see nothing in the config.txt that shows how.
(For that matter why to the other tunnels NOT do this? And why don't bridges block rising smoke columns?)
(For that matter why to the other tunnels NOT do this? And why don't bridges block rising smoke columns?)
