We just learned about the Safety Valve.
Another part of a locomotive is a Sand Dome or Sand Box.
When a locomotive is speeding down the tracks and the metal tracks get wet, sometimes the wheels might slip.
To keep from slipping, the locomotives can spray sand onto the rails as the train is going.
On top of the train is a dome that opens up so the sand box can be filled up with sand when the train stops at the station, just like it does with water.
The sand goes down into a pipe, and when the engineer pulls the right lever it opens up the sand pipe and using some of the steam it can blow grains of sand onto the tracks so the train doesn't slip and slide.
(from: wikipedia - sandbox (locomotive))
Kid Facts - Blast from the past: Electric Motor
