Saltpeter or niter (potassium nitrate), the main ingredient of gunpowder, was essential for the Confederate war effort. To ensure a steady supply, in April 1862 the Confederate Congress passed a bill which created the Nitre Bureau. Its goals were to encourage a more “efficient working of the niter caves” already being mined, to solicit additional contracts for new cave operators or persons leaching earth deposits from underneath buildings, and to establish in the larger towns artificial niter beds. The new bureau was headed by Isaac M. St. John, a former civil engineer, and the South was soon divided into districts, with superintendents assigned to each. Although the focus of the bureau’s effort was in the mountainous regions of Virginia, West Virginia, Tennessee, Alabama, Georgia, and Arkansas, all sections of the Confederacy became involved. Florida comprised District No. 12.
Smith, Marion O.
"Confederate Nitre Bureau Operations in Florida,"
Florida Historical Quarterly: Vol. 74:
1, Article 5.
Available at: https://stars.library.ucf.edu/fhq/vol74/iss1/5