Charcoal was often manufactured nearby from locally available trees, but the heating retorts were typically separated from the other buildings to minimize fire danger. Trees with low value as sources of lumber were debarked, dried, and cut to uniform length to fit into iron retorts with cast iron doors. The retorts were carefully packed to leave as little air space as possible, and the retort doors were closed and sealed with clay to prevent entry of air as the retorts were heated by external fires. Volatile gas generated by the heating process was vented through a small flue at the top of each retort. After the external fires were extinguished, the retorts were allowed to cool before the doors were opened to remove the charcoal.[2]
High purity sulfur usually required little preparation other than grinding to a powder. Separate grinding mills reduced cool charcoal and sulfur to fine powders.[2]
Crude saltpeter (KNO3) was dissolved in a pot of boiling water. After boiling, a small amount of floating glue might be added to the hot water to aid skimming off floating impurities. The hot solution was then carefully decanted to avoid suspending insoluble solid impurities settled to the bottom of the pot. The hot decanted liquid was distributed into shallow wooden vats where evaporative cooling would remove excess water. Purified potassium nitraterecrystallized while the cooling solution was gently agitated with broad hoes to prevent formation of large crystals.[2]
Powdered sulfur and charcoal were combined in appropriate ratios with moist saltpeter crystals, and the moist paste was mixed and compacted by kneading beneath heavy rotating wheels in a press mill.[2][3]
The compressed cake was transferred to a corning mill or kernelling mill to be cut into pieces of approximately correct size by bronze- or zinc-toothed wheels.[2]
Kernelling mill products were sorted by size using leather sieves. Oversize product was returned to the kernelling mill, while undersize product was returned to the press mill.[2]
Sorted kernels of desired size were dried and mixed with graphite to be tumbled in glazing mill barrels. Graphite coating reduced the tendency of grains to stick together in storage.[2]
Glazed product was typically packaged in wooden kegs. Filled kegs were transported away from the mill as soon as possible to a powder magazine for wholesale distribution. The potential for destructive energy release from powder magazine accidents required the magazines to be distant from both the powder mill and other places of business or habitation.[2]
Explosions
This former Laflin & Rand powder mill building illustrates the protective stone walls on three sides after the weaker wooden back wall and roof have rotted away.
Gunpowder is very easily ignited by static electricity or lightning strikes, and most powder mills experienced occasional accidental explosions. Powder mill explosions typically destroyed an entire building and killed those working in the vicinity of the building. Explosions might throw flaming debris which could ignite other buildings. Successful mills were typically built as an arrangement of separate buildings to minimize the loss from any single building explosion. Buildings were separated by enough distance to minimize the risk of being damaged by an explosion in an adjacent building. Buildings were usually built of stone with one weak wooden wall and roof to direct the force and debris from an accidental explosion toward a river or an open field.[2]
Power supply
Powder mills were originally powered by windmills, water mills or horse mills. Despite later availability of steam engines, the older power sources did not require a fire to generate steam, and avoided the possibility of sparks which might ignite the gunpowder. Some 20th-century powder mills used electric power. Before the availability of safe electrical power, some of the most successful mills were built along rivers where water could be distributed through a power canal to individual buildings and intermediate products could be floated from one building to the next. The power canal offered a supply of firefighting water, and the adjacent river was a relatively safe direction to focus explosion debris. Where water transport was impractical, intermediate products were often transported in wagons pulled by draft animals. The wagons were often built entirely of wood held together with wooden pegs, and draft animals were usually unshod to avoid sparks from steel shoes or nails.[2]
^Knight, Edward H.. "Powder-mill" Knight's new mechanical dictionary: a description of tools, instruments, machines, processes, and engineering: with indexical references to technical journals (1876-1880). vol. 2. Boston: Houghton, Mifflin and Co., 1883. 1781. Print.
^ abcdefghijkWhitten, Maurice M. (2012). The Gunpowder Mills of Gorham-Windham, Maine. Windham, Maine: Windham Historical Society. pp. 15–26.
^Braddock, John. A memoir on gunpowder: in which are discussed, the principles both of its manufacture and proof.. Madras: Printed at the Church Mission Press, 1829. Print.
^Rideal, Charles Frederick, and Freeman Morris. A century of success: the history of a great industry ; what it has accomplished ; a record of progress and sustained work : the E.I. du Pont de Nemours Powder Co., from its foundation to the present time. New York, N.Y.: Business America, 19111912. Print.
^Wilson, Mark R. The business of civil war: military mobilization and the state, 1861-1865 (2006) JHU Press p.118
^"Sibley Mill and Confederate Powder Works Chimney". National Park Service. Retrieved 10 June 2019.
^Congressional Serial Set. United States Government Printing Office. 1912. p. 350.
^Dunn, Tony. ".A catalog of .22 Boxes of the U.S.A." (PDF). Roger E. Huegel. Retrieved 14 November 2014.
^Sullebarger Associates, PAST Architects. (PDF). Deerfield Township, Ohio. Archived from the original (PDF) on 2 June 2012. Retrieved 29 November 2014.
^Bridges, Toby. "Black Powder in America". North American Muzzleloader Hunting. Retrieved 15 June 2018.
Wikimedia Commons has media related to Powder mills.
January 26, 2023
powder, mill, powder, mill, mill, where, gunpowder, made, from, sulfur, saltpeter, charcoal, component, powder, mill, taken, from, encyclopédie, published, denis, diderot, circa, 1770, working, example, drawing, above, this, restored, edge, runner, mill, eleut. A powder mill was a mill where gunpowder is made 1 from sulfur saltpeter and charcoal One component of a powder mill taken from Encyclopedie published by Denis Diderot circa 1770 A working example of the drawing above This is a restored edge runner mill at Eleutherian Mills Contents 1 Milling steps 2 Explosions 3 Power supply 4 In the United States 5 Europe 6 ReferencesMilling steps EditCrude grinding and mixing operations such as the Frankford Powder Mill of Philadelphia were a cottage industry until the industrial revolution brought improved product quality through the following procedures Charcoal was often manufactured nearby from locally available trees but the heating retorts were typically separated from the other buildings to minimize fire danger Trees with low value as sources of lumber were debarked dried and cut to uniform length to fit into iron retorts with cast iron doors The retorts were carefully packed to leave as little air space as possible and the retort doors were closed and sealed with clay to prevent entry of air as the retorts were heated by external fires Volatile gas generated by the heating process was vented through a small flue at the top of each retort After the external fires were extinguished the retorts were allowed to cool before the doors were opened to remove the charcoal 2 High purity sulfur usually required little preparation other than grinding to a powder Separate grinding mills reduced cool charcoal and sulfur to fine powders 2 Crude saltpeter KNO3 was dissolved in a pot of boiling water After boiling a small amount of floating glue might be added to the hot water to aid skimming off floating impurities The hot solution was then carefully decanted to avoid suspending insoluble solid impurities settled to the bottom of the pot The hot decanted liquid was distributed into shallow wooden vats where evaporative cooling would remove excess water Purified potassium nitrate recrystallized while the cooling solution was gently agitated with broad hoes to prevent formation of large crystals 2 Powdered sulfur and charcoal were combined in appropriate ratios with moist saltpeter crystals and the moist paste was mixed and compacted by kneading beneath heavy rotating wheels in a press mill 2 3 The compressed cake was transferred to a corning mill or kernelling mill to be cut into pieces of approximately correct size by bronze or zinc toothed wheels 2 Kernelling mill products were sorted by size using leather sieves Oversize product was returned to the kernelling mill while undersize product was returned to the press mill 2 Sorted kernels of desired size were dried and mixed with graphite to be tumbled in glazing mill barrels Graphite coating reduced the tendency of grains to stick together in storage 2 Glazed product was typically packaged in wooden kegs Filled kegs were transported away from the mill as soon as possible to a powder magazine for wholesale distribution The potential for destructive energy release from powder magazine accidents required the magazines to be distant from both the powder mill and other places of business or habitation 2 Explosions Edit This former Laflin amp Rand powder mill building illustrates the protective stone walls on three sides after the weaker wooden back wall and roof have rotted away Gunpowder is very easily ignited by static electricity or lightning strikes and most powder mills experienced occasional accidental explosions Powder mill explosions typically destroyed an entire building and killed those working in the vicinity of the building Explosions might throw flaming debris which could ignite other buildings Successful mills were typically built as an arrangement of separate buildings to minimize the loss from any single building explosion Buildings were separated by enough distance to minimize the risk of being damaged by an explosion in an adjacent building Buildings were usually built of stone with one weak wooden wall and roof to direct the force and debris from an accidental explosion toward a river or an open field 2 Power supply EditPowder mills were originally powered by windmills water mills or horse mills Despite later availability of steam engines the older power sources did not require a fire to generate steam and avoided the possibility of sparks which might ignite the gunpowder Some 20th century powder mills used electric power Before the availability of safe electrical power some of the most successful mills were built along rivers where water could be distributed through a power canal to individual buildings and intermediate products could be floated from one building to the next The power canal offered a supply of firefighting water and the adjacent river was a relatively safe direction to focus explosion debris Where water transport was impractical intermediate products were often transported in wagons pulled by draft animals The wagons were often built entirely of wood held together with wooden pegs and draft animals were usually unshod to avoid sparks from steel shoes or nails 2 In the United States EditThe 1810 census reported 208 powder mills in the United States 2 In 1802 the DuPont family started their industrial enterprises in the United States by building the Eleutherian Mills on the Brandywine Creek in Delaware 4 Four mills were manufacturing 69 percent of United States gunpowder when gunpowder production peaked during the American Civil War They were the DuPont mill the Hazard Powder Company of Hazardville Connecticut the Oriental Powder Company of Windham Maine and the Laflin Powder Company of Newburgh New York 5 The Confederate Powderworks of Augusta Georgia produced 6 000 tonnes of gunpowder from 1862 to 1865 but was dismantled after the war 6 The Laflin company merged into the Laflin amp Rand Powder Company after the war and with the other three large northern mills formed the United States Gunpowder Trade Association in 1872 including the American Powder Mills of Maynard Massachusetts the Austin Powder Company of Glenwillow Ohio and the Miami Powder Company of Goes Station Ohio 7 Most smaller mills were unable to compete with this trade association popularly known as the powder trust although regionally important mills including the California Powder Works of Santa Cruz California the Equitable Powder Company of East Alton Illinois 8 and the Great Western Powder Works of Kings Mills Ohio 9 successfully transitioned to manufacture of smokeless powder cartridges As smokeless powder and high explosives replaced gunpowder for most purposes DuPont became the major manufacturer of United States gunpowder until discontinuing production in 1971 Subsequent production for use in pyrotechnics and antique firearms has been undertaken by smaller firms whose operations are often ended by the persistent hazard of accidental explosions 10 Europe EditNotable European mills include Ballincollig Royal Gunpowder Mills Cork Ireland Faversham explosives industry Faversham England Grenelle Mill France Poudrerie nationale de Vonges Vonges Cote d Or France Waltham Abbey Royal Gunpowder Mills Waltham Abbey Essex EnglandReferences Edit Knight Edward H Powder mill Knight s new mechanical dictionary a description of tools instruments machines processes and engineering with indexical references to technical journals 1876 1880 vol 2 Boston Houghton Mifflin and Co 1883 1781 Print a b c d e f g h i j k Whitten Maurice M 2012 The Gunpowder Mills of Gorham Windham Maine Windham Maine Windham Historical Society pp 15 26 Braddock John A memoir on gunpowder in which are discussed the principles both of its manufacture and proof Madras Printed at the Church Mission Press 1829 Print Rideal Charles Frederick and Freeman Morris A century of success the history of a great industry what it has accomplished a record of progress and sustained work the E I du Pont de Nemours Powder Co from its foundation to the present time New York N Y Business America 19111912 Print Wilson Mark R The business of civil war military mobilization and the state 1861 1865 2006 JHU Press p 118 Sibley Mill and Confederate Powder Works Chimney National Park Service Retrieved 10 June 2019 Congressional Serial Set United States Government Printing Office 1912 p 350 Dunn Tony A catalog of 22 Boxes of the U S A PDF Roger E Huegel Retrieved 14 November 2014 Sullebarger Associates PAST Architects Ahimaaz King House and Carriage House Historic Structure Report PDF Deerfield Township Ohio Archived from the original PDF on 2 June 2012 Retrieved 29 November 2014 Bridges Toby Black Powder in America North American Muzzleloader Hunting Retrieved 15 June 2018 Wikimedia Commons has media related to Powder mills Retrieved from https en wikipedia org w index php title Powder mill amp oldid 1100434927, wikipedia, wiki, book, books, library,
