Caves within the Appalachian Mountains were the most significant source of saltpeter. Earth from the caves was mined and carried in bags or wheelbarrows to be processed either outside or, in many instances, inside the cave. Large wooden hoppers, or vats, were constructed to hold the excavated soil. Water was then poured in and allowed to stand for several days to take into solution the nitrates present in the soil, which was stirred often with wooden paddles. The water would then be collected by troughs at the base of the hoppers.
The work of the "peter monkeys," as the miners were known, was an extremely tiring and dangerous task. Laboring for long hours in the cold and dark environment of a cave, dimly lit with torches that gave off noxious smoke, the workers often crawled into small passages to extract the earth. They also felled many trees to provide wood for the hoppers and to fuel the fires used for boiling. If the processing was done within the cave, all of this material was carried underground. If a water source was not readily available, logs were hollowed out to provide piping for its transport. Wages were low, and often either slaves or conscripted soldiers were employed in the operation.
Carol A. Hill, ed., "Saltpeter," NSS Bulletin (October 1981): 83-131.
Marion O. Smith, "Saltpeter Caves of Georgia," Georgia Underground 18, no. 1 (1981).
Joel M. Sneed, National Speleological Society
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