TIP #537: THE SALTPETER INDUSTRY IN KENTUCKY Many of our ancestors were involved in earlier days in the saltpeter industry. Saltpeter, which is potassium nitrate was something the early pioneers knew a lot about. Like regular salt, their survival depended upon saltpeter. Gunpowder was derived from saltpeter and gunpowder was a necessity for not only hunting for game to feed the families, but to defend themselves from the yet attacking Indians. The saltpeter was derived from calcium nitrate which was found in dry caves and rock shelters, abundantly found in Kentucky. It was a product that was extremely difficult to transport from other major towns, so the pioneers were very careful in taking care of their supplies. A slave named Monk Estill is credited with being one of the first of Kentucky's manufacturers of saltpeter. He supplied the valuable commodity to Fort Boonesborough and Estill's Station as early at 1780's, two of the earliest forts who were constantly under attack. By the year 1805, there were 28 saltpeter caves and rock shelters that were actively being mined. Samuel Brown, M.D. was a professor of chemistry, anatomy and surgery at Transylvania University who wrote extensively on the mining of saltpeter entitled "Great Saltpeter Cave in Rockcastle County. During the War of 1812, the demand for salt peter reached a peak. The U S ports had been blockaded under the British embargo of 1807 and this stopped the importation of saltpeter which had been produced in India. The prices went up and caused the mining efforts to be very profitable for the pioneers. Mammoth Cave in Edmonson County Kentucky became a major source of saltpeter in Kentucky and the remains of the operations are still found in the cave and shown on the tours. Dixon Cave, nearby, was also known for saltpeter manufacturing; both had been mining since 1799. After 1811, most of the soil containing niter was pretty well depleted; and the New Madrid earthquakes of 1811-1812 damaged many of the saltpeter works. In 1812, Kentucky is shown as having produced 300,000 pounds of saltpeter. After the war, production resumed somewhat but prices fell to it's $1.00 per pound to 15 cents per pound and most pioneers could earn better wages elsewhere. After this time, any production was fairly well just for the individual's use. There are 133 caves in Kentucky and six rock shelters that produced saltpeter. Many slaves, likely as many as 70, from Edmonson, Barren and surrounding counties were employed in this occupation at Mammoth Cave and the same would have held true in other caves. It is said that mules were brought into the cave and lowered by pulleys into the caves. How They Did It: (Courtesy Foxfire Volume 5). "Cave dirt was tested for its nitrate potential by the following procedure: A footprint or mark was made in the dirt and left for twenty-four hours. If the print was scarcely visible by the next day, then the dirt was deemed high in niter. "A mattock was used to break up the cave dirt, and a wooden saltpeter paddle was used for digging and scraping The dirt was removed from the cave in gunny sacks and poured on top of the twig and straw in the V-vat. Buckets of water were then poured over the saltpeter dirt to leach it of its nitrate or 'Mother liquor'. The mother liquor (also sometimes called 'beer' ) would run down the sides of the V-vat and into the split-log base and out into the collecting trough. A dipper gourd was often used to transfer the mother liquor into a container. This same liquor was poured again and again over the saltpeter dirt because re-leaching caused more nitrates to be dissolved. According to the old reports, re-leaching went on until the solution was of sufficient density to float an egg. "The next step was to combine the mother liquor rich in calcium nitrate with wood ashes that contain high amounts of potassium hydroxide. The best woodashes for this purpose were made by burning hardwoods such as oak and hickory. The mother liquor was either poured directly over the woodashes or the woodashes were leached in barrels and the leachate directly combined with the mother liquor. Upon combination, a white haze could be seen , and this white precipitate (calcium hydroxide or 'curds' as it was called) would slowly sink to the bottom of the barrel. If the solution contained an excess of calcium nitrate, the product was termed 'in the grease.' An excess of woodashes produced a condition called 'in the ley.' "The wood ash leachate was poured into the mother liquor until the white curds could no longer be seen precipitating out of solution. The remaining solution thus contained the still soluble potassium nitrate. This solution was dipped out into an apple-butter kettle (or"evaporator'), and a fire started under the kettle. Turnip halves were then thrown into the boiling solution to help keep it from foaming and to take up the dirty brown color. Oxblood (or alum) was also added to the boiling liquid and caused the organic matter to rise to the top of the liquid and form a scum which, with continued boiling, was constantly ladled off. After a few hours of boiling, the hot liquor was poured through cheesecloth in order to filter out the remaining scum and organic material. Upon cooling, fine, bitter, needle-shaped crystals of niter (potassium nitrate) formed in the liquor. These crystals were then collected and dried. Potassium nitrate crystals were far superior to calcium or sodium-nitrate crystals because they are non-deliquescent (do not take up moisture from the air) and, hence, would not make the gunpowder wet and unusable. The nitrate crystals thus obtained had to be further refined and purified. This purification procedure was done either by the individual and homemade into gunpowder, or it was done after the saltpeter crystals were sent to a refinery where the final gunpowder was made." (http://www.dangerouslaboratories.org/foxfire5.html) Information from the Kentucky Encyclopedia. Other information can be found at: http://www.cr.nps.gov/nr/twhp/wwwlps/lessons/35mammoth/35facts2.htm http://www.caves.org/conservancy/gsp/articles/engle.html (c) Copyright 21 Apr 2005, Sandra K. Gorin Colonel Sandi Gorin SCKY Links: http://www.public.asu.edu/~moore/Gorin.html Sandi's Puzzlers: http://freepages.genealogy.rootsweb.com/~gensoup/gorin/puz.html Gorin Publishing: http://ggpublishing.tripod.com/