Second that. Letting a boiler go dry is a very bad thing. I believe the same still holds quite true for modern turbine systems and even on the secondary side of steam generators for nuclear implementations using "hot rocks" as the heat. (Can even be more tricky if there's a condensing side on the circuit, but I don't think the old steam engines had to worry about too much water and vacuum problems.)

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Barbequed Pixels?

Your friendly neighborhood Wings3D nut.
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There might be something worth downloading.