"I would think in the late unpleasandness the technology was not able to control the mix of the various powders. I think it was more of an art than a science. What say you?"

Frank, the Chinese in the thirteenth century pretty much had the proportions of saltpeter, sulphur, and charcoal worked out for making powder. They even added other chemicals to make fireworks colorful. With straight gunpowder, the burn rate is controlled by the fineness of the grains; hence FG, FFG, FFFG and FFFFG for priming powder. E.I. DuPont and others invented machinery to form, dry and grind powder. Occaisionally something went wrong and a huge explosion resulted. Black powder measures are always made of brass, to avoid static electricity. By the time of the WTBS, the manufactury of black powder was more science than art. Creating fireworks is the art. No doubt cannon cockers have a whole different slant on all this. Stan