On Rice and Rice Mills
Miss Genevieve often needed to explain the role of engineers and engineering in the rice industry in South Carolina to Garden visitors.
To understand the importance of the job of rice mill engineer, I need to explain some of the details of growing and processing rice, the crop that supported the entire plantation economy in the Carolina Lowcountry for over two hundred years.
Growing rice is a long and complicated process involving the periodic flooding and draining of rice fields. In the 1600s, settlers in South Carolina raised small amounts of rice as an upland crop, depending on sometimes-uncertain rainfall for the flooding. Later they developed a more reliable method of growing rice in the inland swamps.
Finally, about the middle of the 1700s, the planters (or some say, their African slaves) devised a much more efficient way to grow rice by using the tidal flow in the coastal rivers to flood and drain the rice fields. The process was complicated but suddenly rice planters could grow huge quantities of rice (always remembering that the slaves really did the actual work, of course). Processing the rice for market was a different story, however!
In the early days, once the workers had grown, harvested, and threshed the rice—that is, had removed the rice grains from the stalks—they stored the rough rice in the rice barn. At that point, the risky part of the harvest had ended. The year’s crop was safe from ricebirds—which we call Bobolinks today—windstorms, freshets—which are floodings caused by rains upstream—and the hurricanes that could destroy a whole year’s crop in a single day, and unfortunately commonly came during the harvest season.
Most planters declared a holiday for their workers as soon as the rice crop was in the barn. Feasting, singing, dancing, and all forms of entertainment celebrated the successful harvest. But once the celebrating ended, the tedious task of processing the rice for market began.
A rough, inedible husk covered each rice grain. In the first step of processing, the "first pounding," workers pounded the rice with a wooden pestle in a large wooden mortar to remove that husk. You can still see an old mortar and pestle on display in the Old Kitchen here at Brookgreen Gardens.
To make this pounding equipment, workers hollowed out a cavity about one foot deep in the top end of a two- or three-foot-long section of tree trunk for the mortar. They also shaped a four-foot-long pestle from a smaller tree trunk. It had a bullet-shaped foot-long head that fit into the hollow of the mortar and a central shaft about as big around as an oar, so that the worker could grip it solidly.
To use the mortar and pestle, the worker placed a small amount of rough rice in the hollow. Holding the pestle vertically, he or she then used the heavy end of the pestle to pound the rice in the cavity, knocking the husk off the rice kernel by moving the pestle up and down, up and down, with a twisting, rolling motion. Not only was this time consuming, but pounding, pounding, up and down, hour after hour was tiring.
After knocking the husks off the grains of rice in the mortar, the worker transferred the mixture of rice and loose husks to a flat fanner basket two feet wide for winnowing. To winnow the rice, the worker tossed the grains of rice and husks into the air with a quick flip of the basket, while a helper fanned the basket to create a breeze. The breeze carried away the lighter husks, while the heavier rice grains fell back into the fanner basket.
In later years, planters built winnowing houses on stilts. Then, after the first pounding, workers carried the mixture of rice grains and husks up into the winnowing house and dropped it through an opening in the floor on a breezy day. Even later, large fans turned by animals or workers created the breeze to blow away the husks while the heavier rice fell straight down.
Even after winnowing, the rice grains were not yet ready for market. Brown bran and germ layers still covered the inner kernel. Although these layers contain healthy vitamins and minerals, they spoil rapidly in storage. Therefore, the next step in processing required removing these brown bran and germ layers. So, back to the mortar and pestle went the brown rice for the second pounding or "polishing."
Polishing took much more skill and care than the first pounding. At this stage, the rice needed to be pounded just hard enough to remove the outer brown layer but not hard enough to break the rice grain itself. Only whole grains of rice could be sold on the world market. A skilled worker, using a tapping and rolling motion, could polish almost all of the grains of rice without breaking them. A poorly skilled or tired worker broke as many as half of the grains.
Once pounded the second time, the rice went back into the fanner basket or to the winnowing house where the same fanning process again separated the heavier rice grains from the lighter bran and germ. These layers became animal feed. Workers then sent the polished white rice grains through sieves to sort them into three separate piles: the whole polished grains, the larger broken grains called “midlins,” and the small broken pieces and flour called “the fine.”
Workers packed the whole polished grains of rice, which hopefully made up most of the crop, into barrels and barged them down the river to Georgetown or shipped them to Charleston for sale on the international rice market. Planters sold the midlins locally or ate them themselves. Slaves received the fine as part of their weekly food ration.
As you can see, hand methods for processing rice took a lot of time and effort, even more than clearing and maintaining the rice fields and growing the rice. In fact, once the tidal flow system of production gained widespread use in the Carolina Lowcountry, plantations began producing far more rice during the growing season than their workers could process throughout the rest of the year.
As you can imagine, great efforts went into developing machines that could process the rice more quickly and efficiently than the hand method. Inventors continually experimented with different machines and techniques, with what has been called "a remarkable lack of success."
Finally, in the late 1700's, a South Carolina engineer named Jonathan Lucas invented a rice mill system that revolutionized the rice industry in the same way that the invention of the cotton gin revolutionized cotton production.
Mr. Lucas’ first rice mills used millstones driven by waterpower to separate the husks from the rice and thus eliminate the first pounding. A hand mortar and pestle were still needed for the second pounding, or polishing, to remove the bran and germ layers from the rice.
However with further work, Mr. Lucas discovered how to adjust and refine his invention so that mechanical mortars and pestles turned by river currents or tidal flow were able to complete the polishing as well. At last, rice processing was able to keep up with rice production.
Before the turn of the century, Mr. Lucas constructed several water-powered rice mills at plantations on the Waccamaw and Pee Dee Rivers. He built his first steam-powered rice mill in Charleston in 1817. During the first half of the 1800s, Mr. Lucas’ rice mills helped rice planters in the Carolina Lowcountry become the wealthiest men in the United States.
A rice mill required an expert engineer to keep it working properly. Not only did the mechanical machinery need to be in good operating condition, but the millstones and other parts had to be kept in proper alignment and just the right distance apart to accomplish their tasks without crushing the rice grains.
Additionally, by the middle of the 1800s when steam powered most rice mills, the engineer needed to keep the steam-generating equipment in good repair. Boiler explosions commonly caused property destruction and loss of human life in any equipment they powered, whether it was railroad locomotives, sawmills, or steamboats. So, a good engineer not only kept the rice mill operating efficiently, but also kept the rice mill workers alive.