Home | Sultans

Making Charcoal (stack wood method)


Fuel For The Fires: Charcoal Making in the Nineteenth Century

(In memory of Ted Ziegler and Ken Krause)

The making of charcoal, literally the distillation of wood to its carbon content, was an important process during the first half of the nineteenth century. Because it burned hotter and cleaner, charcoal was considered superior to wood. It provided fuel for both the furnaces which produced the iron and the forges of the blacksmiths who shaped it.

The first person to discover the seemingly magical properties of charcoal has long since been lost to human memory. What is known is that it may have been used in Europe as early as 5,500 years ago and was the "smelting fuel of the bronze and iron ages." Across many centuries charcoal was used in the smelting and shaping of metals, the production of glass, as a purifier of food and water, and in gunpowder; its by-products included a liquid used in the Egyptian embalming process.

The first method for producing charcoal probably involved the pit kiln process in which wood was slowly burned in a shallow pit covered with soil. However, in many areas this eventually gave way to the more efficient and more manageable above ground forest kiln method. The charcoal maker, or collier, became an important figure. The demand for charcoal was such that in areas like Great Britain the woodlands were all but stripped and alternative fuel sources such as coke had to be sought. This was not initially the case in the heavily wooded United States.

The chief customers of the American collier were the ironmaster and the blacksmith. Prior to 1840 the great majority of iron produced in America came from bloomeries and forges fueled by charcoal. Charcoal-produced pig iron possessed qualities important to the rural economy of colonial America and the new nation of the United States. It was malleable hot and cold and made an excellent metal for the blacksmith who had to fulfil many needs for his customers.

Charcoal making was usually the most time consuming, and second most expensive, aspect of iron production. Like many ironmaking operations it was to a certain extent governed by nature. Since optimal charcoal making conditions included dry weather and little wind, it was usually attempted from late spring through early fall. At some furnaces, half of the workforce was in some way involved in charcoal production.

Charcoal making could be a nearly full time job in the eastern iron producing areas. This was particularly true at the Hopewell Furnace in Pennsylvania where it took the yield of approximately one acre of woodland a day to feed the voracious furnace. From late March through early November colliers spent a great deal of their time at the burn sites, usually located in the surrounding woods. Living in their conical collier's huts, they would tend as many as fifteen piles (sometimes made up of 20-50 cords of hardwood) with their assistants. When the final raking out was done and the charcoal cooled it was loaded onto wagons and hauled to the furnace. During his "off-season," the collier might cut wood, mend his tools, or do other jobs at the furnace.

Colliers were not merely limited to iron producing regions. Their efforts fed the fires of blacksmiths and other craftsmen throughout the young nation. It appears there were few men in the midwest who could call themselves full-fledged colliers. One of the very few to bear that designation was Zachariah Collins of Marion County, Indiana, who supplied charcoal to local blacksmiths and carriage makers. He may also hold the dubious honor of being the only collier in American history killed by one of his customers because of the quality of his product. In 1836 Collins was slain by Indianapolis carriage maker Arnold Lashley. The two men argued after the carriage maker had twice rejected loads of charcoal as too full of dirt. A fight ensued and Collins later died from blows to his head.

Most involved with charcoal making in the midwest did it as a sideline or in conjunction with their trade. It is likely that some farmers earned extra income from charcoal making by producing it themselves or selling trees cleared from their land to those who did. Since blacksmiths were among the prime consumers of charcoal, they also tried their hand at charcoal making. An early resident of Bethlehem [now Carmel], Indiana recalled local smiths "burning their kilns right in the street."

The amount of charcoal used by the average smith is difficult to determine. Consumption would depend greatly upon the type and amount of the smithy's trade. Hoosier blacksmith Henry Shafer purchased a minimum of 340 bushels (at twenty cents a bushel) of charcoal for his thriving business from 1835 to 1837. Shafer also bought at least 100 bushels of mineral,or stone, coal during that period, again at twenty cents per bushel. Most smiths burned charcoal in their forges because it was easy to light, low in sulphur, and readily available. However, it was fast-burning and difficult to control and mineral coals also found their way into the forge.

Nationwide, the demand for charcoal remained relatively high until the 1850's. One of the most unusual uses for it was as a road paving material. Timber rich Michigan and Wisconsin tried it in the 1840's. The roadway acted as the burn site and the raked out coal formed the road surface. At a cost of $500 to $600 a mile it was cheaper than limestone, but wasteful.

After the Civil War the demand for charcoal declined as new technologies allowed for the use of the cheaper mineral coals. The cost of charcoal began to outweigh its benefits for both the ironmaster and the smith. New techniques of charcoal production were introduced, such as the permanent brick kilns constructed at Hopewell, but they failed to slow progress and could not prevent the slow fading away of the collier and his world.

Making Charcoal

The collier's job began after he or the woodcutter had provided wood for the burn. Hardwoods like oak, ash, and hickory were the best types, but nearly any kind but resinous trees like pine were acceptable. Aged, dried wood was the best. The wood was cut into four foot lengths and split into 1-4 inch widths called lapwood and 4-7 inch pieces known as billets.

The area, or hearth, in which the pile/kiln was to be constructed was cleared and leveled. The hearth was usually approximately forty feet in diameter and slightly raised in the middle (similar to a pitcher's mound) to provide drainage. A ring of soil, cleaned of stones and organic matter, was placed outside the hearth. Leaves to cover the pile were placed outside the ring.

Building the Pile (Kiln)
The first step in constructing the pile was the placement of the center pole, or fagan. The fagan, approximately four inches in diameter, was surrounded by a triangular chimney made of 18 inch long split wood. Concentric rings of billets were placed around the chimney. The billets were flared outward at the base to provide the proper pitch. They sometimes rose to three or four tiers in the largest burns. Lap wood and a chinking of charred wood were used to fill in the spaces around the billets. The chimney was then half filled with kindling.

On the day of the firing the pile was covered with leaves and 1-3 inches of soil (sod replaced them in some areas) to control the burn. The chimney was then filled to within a foot of the opening.

The Burn
Most often the pile was "charged" by dropping burning charcoal into the chimney and covering the opening with a "bridgen" of three billets (the ever experimenting Thomas Jefferson lit his pile from the bottom). If the burn proceeded properly, the "fire" burned downward and out, like a cone. The pile had to be watched until the final raking out of the charcoal. The collier and his assistants kept a wary eye on the steaming, smoking pile to guard against blowouts that might lead to a flaming of the pile. If blowouts occurred, the dirt remainingin the ring was used to seal them. Controlling the oxygen to the pile was a delicate matter. Too much might mean the pile would catch fire, too little would result in an unsatisfactory burn. Colliers often had to cut or dig holes at various spots on the pile to ensure proper air flow.

During the first twenty-four hours the collier had to occasionally "jump the pile." This dangerous task, which required the collier to climb atop the smoking mass, was to compact the pile and assure an even burn. As the burn continued and the smoke and steam subsided, the raking out began. Long-tined charcoal rakes were used to rake the already produced charcoal from the top and perimeter. The tinkling sound it made as it fell told the collier he had a good batch. Dirt from the ring was again used to cover the raked spots and the burn continued.

Depending upon the amount and types of wood used the burns might continue for three to ten days. Their yield again depended on conditions and wood types, but it was not unusual to average 35-45 bushels of charcoal per cord of wood. From there it was hauled to furnace and forge.

Timothy Crumrin is Historian and Archivist at Conner Prairie Museum in Fishers, Indiana, and a certified journeyman collier. He is the author of Voice of the Hammer: The Art and Mystery of Blacksmithing and numerous scholarly articles.

Previously published in Chronicle of the Early American Industries Association (June, 1994).

Photos by Leo E. Landis

Copyright 1996, Conner Prairie