This authentic brick kiln in Historic Williamsburg, Virginia, is a replica of that was used by colonists. There weren’t brickyards back then. The era’s wooden wagons and crude roads were not capable of transporting the massive tonnage of bricks. So itinerant brickmakers built their kilns on the grounds of a client’s house construction site. (Photos: Hoag Levins)
Three of the earliest building material industries in the European colonial settlements in North America — carpentry, glass making, and brickmaking — were all endeavors well suited for the southern New Jersey colony with its vast forests, deep deposits of silica sand, and equally deep veins of the best kinds of clays for making bricks. These enterprises made their owners fortunes by servicing the wealthiest colonial families that could afford fancy brick mansions with widowpane glass and patterned brick architectural decorations that were all exorbitantly expensive. But that was also the point. In that material culture bereft of the glut of the products and services we live with today, the materials one used to build one’s house spoke the loudest of one’s social status. (See companion article about South Jersey’s patterned brick houses.)
A colonial government building in Williamsburg, Va.
A patterned brick house built in colonial South Jersey.
A variety of clays suitable for brick making run beneath the counties of southern New Jersey (which was known as West Jersey in colonial times). The deposits are shown on this century old geologist’s map.
The consistency and colors of raw clay, much like those of the bricks they produced, varied wildly and could be further altered by adding different kinds of sand and substances like ash into the mix.
The clay was dug out, cleaned of rocks and debris, and loaded into a treading pit. Water and sand were added as feet stomped the mix into the even consistency of dough.
The resulting material was shoveled onto brick forming tables.
The wooden brick molds used to form the bricks were first coated with sand so the clay wouldn’t stick.
The clay was worked down into the mold, and then the excess was cut off to finish the molding.
Called “green” bricks, the newly molded wet bricks were carried to a drying section of ground covered by sand.
Because the drying process could take as long as a month, the green bricks were often loaded into temporary sheds to protect them from rain.
The walls of the 20-foot wide kiln were made of already-fired bricks. Then, as many as 20,000 green bricks were stacked inside the kiln that was tented to prevent rain from turning the green bricks into mud.
Four “tunnels” were built across the bottom of the kiln to hold the fires that baked the green bicks.
The entire exterior and top of the kiln were covered with a thick coating of clay to hold in the heat and prevent excessive oxygen intake that could overheat the fire.
Enabling the kiln to fire the bricks required maintaining temperatures close to 2,000 degrees fahrenheit, consuming enormous amounts of wood fuel.
Workers had to stoke the fires 24 hours a day for a week to ten days to fire the bricks thoroughly. Once firing was done, the kiln had to cool for a week or more so as to not crack the bricks with sudden temperature changes.
After cooling, the kiln was disassembled. It can be seen here how the bricks that were closest to the firing tunnels had their ends burned black.
No glaze or other additive was used to achieve the black end on bricks. Their proximity to extreme heat of the fire tunnels slightly melted them and drew salts out of the clay.
After the blackened brick ends were polished, they served as the crucial element in most of the decorative architectural work like this wall of Historic Pomona Hall in Camden County, NJ.
The finished red bricks were stacked near the construction site so brick masons had easy access to them.
Oyster shells played an important role in the brick construction process. They were burned at a high temperature to produce quicklime that was mixed with sand and water to create the mortar used to adhere the bricks together.
