[locojoe]

When I was working on N7s at Enfield the fire sometimes needed cleaning at the end of a run. So before reaching our destination, if the fire was too big, firemen would ask the driver to knock it about a bit. He would then work the engine very hard only nicking up the reverser just a bit. At night the result of this was a grand fireworks display,
The engine would then emit huge showers of sparks chucking the unwanted fire out through the chimney. This was ok in London where we worked, but if you did this out in the sticks there was a good chance of catching the fields alight.