Hopewell volunteers demonstrate the art of charcoal making

Long before the days of backyard barbecues, when a trip to the store is required to buy charcoal for the grill, charcoal was made by hand through a slow wood-burning process.

At Hopewell Furnace National Historic Site, volunteer charcoal makers, called colliers, re-enacted the traditional 19th-century method of making charcoal by lighting a pit filled with wood and keeping it burning over the course of eight days. The spring charcoal burn began on May 13, and it lasted for 24 hours a day through May 20. Volunteers manned the site throughout the week as the wood in the pile "cooked."

According to the National Park Service, charcoal was used to fuel the furnace because its burning provided the intense heat needed to form iron. A large amount of charcoal was required to keep a furnace the size of Hopewell's running. When it was "in blast," the furnace would consume 800 bushels of charcoal per day.

In the early days, charcoal-making was done in the woods surrounding the furnace, and the finished product was transported back to the location. "The charcoal pit would not have been here," said Jeff Jones, site manager. "Originally what they would have done was cut down the trees in the areas in the hills, and where there were level surfaces, that's where they would build the (charcoal pit)." He noted that because charcoal is a lot lighter than wood, it could be more easily transported.

For the recent demonstration, volunteers used wood from oak and ash trees, which was stacked around a "chimney" and then covered with leaves and dirt to keep out the oxygen. The charcoal pit was lit using burning coals from a nearby campfire.

Volunteer Clifford Brahmstadt explained that colliers were not trying to burn the wood. Rather it is left to "cook" to remove the sap and moisture to extract the carbon.

"The fire will burn down through the chimney and spread out," explained Brahmstadt, noting that volunteers monitor the pit to make sure the wood keeps "cooking." "People in the night shift watch the fire to make sure it doesn't go out and to make sure that it doesn't vent. As it burns out, vents will start to open up that have to be closed."

When the charcoal was ready, it was removed from the pile and left to cool. "We rake the charcoal out into concentric circles and let it cool to make sure it is cold before being loaded into the wagon," Brahmstadt said. "We let it (cool) for a day and then haul it to the charcoal barn."

Samples of charcoal made at Hopewell can be purchased in the park's visitors center.

Other events on May 13 included the annual shearing of Hopewell's sheep, as well as fiber arts, blacksmithing and gardening demonstrations provided by volunteers and Hopewell park rangers, who also offered information about the history of the site.

Hopewell Furnace is located at 2 Mark Bird Lane, Elverson, about 5 miles south of Birdsboro off Route 345. The park's facilities are currently open on Wednesdays through Sundays from 9 a.m. to 5 p.m. Admission to the park is free.

For more information, visit http://www.nps.gov/hofu or http://www.facebook.com/HopewellFurnaceNHS.