Kalen McNabb stopped and shone his flashlight a second time on the foundation wall of the old church. Trained as an architectural conservator, he had seen this in his textbooks but this was the first time he had encountered it in the field. A second look, a closer examination as he stood hunched over in the pre-Civil War church’s crawlspace and threaded through spaces infested with thousands of spider crickets, and he knew he was right. The tiny red specks in the mortar that bonded the bricks of the foundation were brick dust, further evidence that the builders of Abbeville’s Trinity Episcopal Church spared no expense when they erected their Neo-Gothic “mini-cathedral” in 1860.
McNabb had already determined, before he started crawling underneath the church, that the foundation of the 166-year-old church was remarkably solid. The presence of brick dust in the mortar, those tell-tale red flakes, were further evidence that the men who commissioned the building were intent on guaranteeing a long and sturdy life for their beloved church. McNabb noted that Trinity’s brick dust was finely ground, intentionally sieved before being mixed into the mortar. The masons hired to build the church were obviously masters of their craft and well versed in the history of mortar technology. Brick dust is considered to be a pozzolan, a powdered material added to brick dust to increase its durability. Because so few references to pozzolans appear in modern times prior to the 18th century, scholars believe their use may have fallen out of favor toward the end of the Roman Empire. A Frenchman, L.J. Vicat, wrote a treatise in 1837 on mortars and cements and included information on types of pozzolans, thus reviving interest in their use. But it wasn’t until the late 19th century that pozzolans became popular in engineering and building projects.
There are many additional clues that indicate that Trinity’s pre-Civil War church members intended their building to be an architectural gem. The stucco or rough cast, a combination of water, river sand, and lime applied over the brick walls to provide a finished exterior surface for the church, contains natural cement that likely came from the Rosedale Formation in New York. The bell, which still hangs in the steeple, came from the top iron foundry in South Carolina. And the chancel window, another window, and the roundels topping all the other windows in the church were ordered from New York City, from the studio of William Gibson, known as “the father of stained glass painting in America.”