The Texas Hill Country’s abundant caves with their significant bat populations furnished an important resource for the Confederacy during the Civil War. Bat guano’s high nitrate content provided a key ingredient for the production of gunpowder, and by 1863 a shortage of munitions and other goods precipitated by the Union blockade, prompted the South to seek alternative means of securing various supplies. The Nitre and Mining Bureau of the Confederacy authorized local industrialists to mine bat guano from area caves in order to extract saltpeter. The Thomas Anderson mill in northwest Travis County, for example, was designated the Travis Powder Company in 1863 and obtained guano from area caves to extract saltpeter and mix it with sulfur and charcoal (produced by burning cedar trees) to manufacture gunpowder. A similar operation occurred near Concan in Uvalde County where a cave and its resident bat population fueled that region’s saltpeter industry. Miners utilized mule-drawn railcars to transport the guano.

By summer 1863 the Nitre and Mining Bureau, Western District, Texas, authorized William Seekatz and Associates to operate a guano kiln in New Braunfels in South Central Texas. Capt. William Seekatz, one of the pioneers of New Braunfels, along with citizens Ed Braden, Ed Dreiss, Jack Marshall, and Joe Ney, constructed a limestone oven near the headwaters of the Comal River. On July 17, 1863, the Neu-Braunfelser Zeitung stated that the men were waiting for the Confederate government to supply kettles for operations to begin.

Guano was mined and hauled from Brehmer’s Cave, some three miles west of the oven as well as from a cave in the Cibolo area. From the guano, the kiln produced an output of 100 pounds of pure saltpeter daily. According to the Neu-Braunfelser Zeitung on April 29, 1864, 100 pounds of guano were needed to produce four pounds of saltpeter—requiring the shoveling of 2,500 pounds of bat guano a day to fill the quota of 100 pounds of saltpeter crystals. Regular production continued presumably until the end of the war.

In 1938 Frank P. Seekatz, the son of William Seekatz, erected a granite marker to commemorate the operations that had begun seventy-five years earlier. The marker stands by the remnants of the guano kiln in present-day Landa Park.