We just learned about the Air Brakes.
Another part of a steam locomotive is the Smokebox.
This is the place on the front of the locomotive where the hot air and smoke goes to.
The coal burns up and the hot air goes through the boiler.
After that the hot air needs to be released, so it goes into the smokebox and then out the chimney.
Because the smoke is so dirty, it leaves a bunch of ashes in the smokebox, so the front of the train can be opened up and cleaned out when it gets too dirty.
(from: wikipedia - smokebox)
Kid Facts - Blast from the past: Stator