Gunpowder: Difference between revisions

For the most powerful black powder, [[meal powder]], a [[wood]] charcoal, is used. The best wood for the purpose is Pacific [[willow]],<ref>{{cite book|author=US Department of Agriculture|title=Department Bulleting No. 316: Willows: Their growth, use, and importance |year=1917|page=31|url=https://books.google.com/books?id=x20TAAAAYAAJ&q=black+powder+willow&pg=RA15-PA31|publisher=The Department}}</ref> but others such as [[alder]] or [[buckthorn]] can be used. In Great Britain between the 15th and 19th centuries charcoal from [[alder buckthorn]] was greatly prized for gunpowder manufacture; [[Populus sect. Aigeiros|cottonwood]] was used by the American [[Confederate States]].{{sfn|Kelly|2004|p=200}} The ingredients are reduced in particle size and mixed as intimately as possible. Originally, this was with a mortar-and-pestle or a similarly operating stamping-mill, using copper, bronze or other non-sparking materials, until supplanted by the rotating [[ball mill]] principle with non-sparking [[bronze]] or [[lead]]. Historically, a marble or [[limestone]] edge runner mill, running on a limestone bed, was used in Great Britain; however, by the mid 19th century this had changed to either an iron-shod stone wheel or a [[cast iron]] wheel running on an iron bed.<ref name="earl-2" /> The mix was dampened with [[ethanol|alcohol]] or water during grinding to prevent accidental ignition. This also helps the extremely soluble saltpeter to mix into the microscopic pores of the very high surface-area charcoal.