Powder mill

A powder mill is a mill where black powder, a type of gunpowder, is made.

Powder mills were driven by a power source such as windmill, water mill or horse mill, and contained rollers for grinding or a pilon for pounding the ingredients of gunpowder together, as well as presses and tumbling barrels and sieves for compacting, granulating, drying, grading and packaging the powder. Powder mills were built with an eye towards mitigating the danger of explosion, usually with one or more walls built purposely weak so that the force of an accidental explosion could be directed towards an open field or a river.