The Salt Furnace at Holman Springs, Sevier County

By Carl Drexler, SAU Research Station
Feature of the Month - September 2022

The recent Arkansas Archeological Society Training Program at Holman Springs recovered, as we expected, tens of thousands of pieces of broken Caddo pottery. It also uncovered something we did not expect, and this surprise is our Feature of the Month for September.

Holman Springs, like several other sites in southwest Arkansas, is a place where briny water seeps to the surface. These places drew people and animals to them for millennia, as sodium is a necessary part of the diet (particularly in the hot summer months). Making salt from brine is a simple process; you just evaporate off the water. How you do that changes with time and culture. We see this change at Holman Springs.

For centuries, the Caddos made salt at Holman Springs by placing pots of brine over fires, then using the heat of the fire to evaporate off the water (Kenmotsu 2005; Eubanks 2021:149-150). Simple. Effective.

When American settlers came to the area in the 19th century, they also made salt from the brine, but they did it very differently. Their operation was much larger and intensive. Rather than boiling water off in individual clay pots, they constructed a “salt furnace,” which we excavated this past summer.

A salt furnace is a carefully designed structure used to reduce brine to salt. Salt furnaces were commonly built of brick, and would have a hearth at one end, where a fire burned, and a chimney at the other. Between the two were two low brick walls and supports that would create an air channel to draw the heat from the fire up to the chimney. On top of this channel sat a line of cast iron pots, often starting in a large size and getting smaller nearer the chimney.

Operators placed brine drawn from a well or straight from a salt pond into the first kettle and let the heat of the fire drawn underneath evaporate off some of the water. As the concentration thickened, the mixture would be moved to the next smaller pot and the larger one refilled. This happened numerous times as the brine reduced and would eventually leave behind a clump of salt that could be packaged and shipped.

To be honest, we did not expect to find the salt furnace at Holman Springs. Previous excavations at the site included test units on either side of it, but nobody actually dug into it. We had no indication that it was there before we encountered it.

Our first indication that something was there was a collection of in-place bricks that showed up in the wall of one unit (Figure 1). We had seen notes about displaced brick in notes from earlier digs, but these were coursed bricks, sitting undisturbed in the ground. We opened another excavation unit to explore them further, and what we found was astounding: a solid base of brick for the support walls, that would hold the kettles, terminated at a rectangular alignment that was likely the chimney base at one end of the furnace (Figure 2). An excavation unit opened just to the east of the chimney base showed no intact brick but significant fire-reddening of the soil. So, we had the end of it!

Going in the other direction (to the west), well, we didn’t find the end of the feature. We ran out of time. But we know the orientation of the furnace even if we don’t know its full extent. We had to work through the brick rubble to get to the intact brick beneath, which makes for slow digging and precarious footing (well, kneeling).

Now, when we look at this feature, we must understand what it meant in context. Archeologists love to talk about context. The furnace meant a lot of different things beyond it being a place to boil water.

Rather than selling it outright, as it did with other land, Arkansas’s government issued licenses to land containing salt works. The money coming in from those licenses supported the construction of roads and schools, particularly for local orphans. So, the furnace also meant funding infrastructure in the early stages of Sevier County (Littlefield 1973).

The furnace also meant a very different approach to resource use in the area. Whereas the Caddos maintained a large, diffuse fire, and made it when they needed it, the furnace was kept going around-the-clock, with a hot fire burning constantly. This would be arguably more efficient, as the fire and chimney arrangement trapped and channeled heat, but would have been ultimately more aggressive in its consumption of fuel. The way this resource relied on the natural environment was very different from what people did before.

The production of salt also links into very different foodways between Caddo and Settler communities. Settlers frequently used salt as a preservative for food. Salting meats was a common way of preservation in a period before refrigeration, and pickling, brining, and the application of salt was a way of making food last, either for later consumption or for shipping for long-range sale. Native American communities are not known to have done this. Salt would be used to flavor food, fix dyes in fabrics, and other things, but we do not think of it as being a preservative.

One of the great aspects of this excavation is that salt production in the 19th century is best studied in places like Saltville, Virginia, where industrialized production took on a massive scale. Focused research on saltmaking in a rural context in the United States is not a well-understood process, so this feature is significant in understanding this different dimension. We look forward to learning more about it in the future.