Fire In the Hole!
March 2008 Updated Jan 2012
By Van Wagner
Black powder was the explosive that made mining iron ore in the Danville area possible from the 1830’s until mining ceased about 1890. Although blasting powder was almost certainly imported to local mines from all over the world, Danville did have at least 1 powder mill. The location was on the south face of Montour Ridge, about 1 mile East of Mahoning Gap. Today this area is known as “Powder Mill Hollow.” The road there is now named “Powder Mill Road.” The exact location of the mill is not currently known, however, the charcoal pits are still evident in the area. Many people are aware that charcoal was used in the iron industry before the introduction of Anthracite coal in blast furnaces however it is also a key ingredient to making black powder.
To make black powder charcoal was mixed, in specific proportions, with Sulfur and Sodium Nitrite (also known as Salt Peter). Sodium nitrate is derived from both bat and bird droppings. In caves where bat colonies had created thousands of years of droppings, the waste was mined and referred to as “guano.” It is also possible to use bird waste to create sodium nitrate. It is unclear what the source was for Danville’s mill. In the Wapwallopen powder mill near Nescopeck, guano was imported from Chile, South America.
Sulfur is a native element mined from the earth. It is most common in areas of volcanic activity. Again, it is unclear from where Danville’s powder mill obtained sulfur. It is safe to assume that it was not mined locally as there is no evidence to support local sources of sulfur.
What we did have locally was wood for charcoal. Hardwood charcoal was not ideal as it was too high in ash. The best charcoal for black powder was that made from grape vine, soft pines, alder, or willow. It is unclear what local wood was used but if the charcoal pit locations on Sidler Hill were indeed related to the powder mill, I suggest that it was pine and grape vine as alder and willow are wetland tree species.
The powder mill itself probably had several structures. One such structure may have been the “soda house.” This was the term for a building where sodium nitrate was refined. At the mill would have been a means to grind the ingredients into a powdered mixture. At other mills in the 1800’s waterpower was used. However, the small creek that flows out of Powder Mill Hollow is not large enough. Perhaps a donkey or mule gin was used. In the grinding and mixing process a small amount of water had to be added to prevent sparking and explosions.
Next wooden shovels were used to manually move the powder to the “Corning Mill” where it was formed into pellets of particular sizes. Powder for fire arms is very fine while powder for blasting rock in mines is a very course grain. Finally the dried powder was loaded into wooden barrels in the “can house” and shipped to mines, quarries, canals, farms and railroads.
Black powder is extremely deadly and has caused many deaths around the world both in manufacturing and where it was used for blasting. An explosion in 1879 reportedly destroyed Danville’s powder Mill. A March 15, 1879 report from the Marion Daily Start (Marion Ohio) reported "The Mahoning Powder Works at Danville PA were completely demolished by an explosion yesterday and three men were blown to atoms."
In 1867 Alfred Nobel invented dynamite, which would eventually make black powder obsolete. Dynamite was far more powerful, about 1000 times, and much safer than black powder. Nobel created his explosives to make conditions safer for workmen who handled explosives. He was later an advocate for world peace when he saw his invention misused as a tool for warfare.
Special thank you to Roger Gilbert of Wapwallopen who provided information about the Wapwallopen mills. More info can be found at his website:
More information about Danville iron ore mines can be found at