Cunningham Falls State Park

Historic Catoctin FurnaceCatoctin Furnace

The history of Catoctin Furnace represents in microcosm the history of the Industrial Revolution in America. From 1776 to 1903 different iron companies mined the rich ore banks near Catoctin Mountain, smelted it in furnaces, and cast both raw pig iron and iron implements of every description.

The earliest settlers to enter the Monocacy River Valley at the foot of Catoctin Mountain arrived in the 1730's. They were a mixed breed of second generation English-Americans and first generation immigrants from the German Palatinate seeking religious freedom. Native Indians were few in this particular area, although the mountain was named for a local tribe known as the "Kittoctons." Lord Baltimore's liberal land policy was instrumental in attracting the first settlers. By 1760 large numbers of Swiss and Scotch-Irish joined the English and Germans.

As is usual in pioneer societies, the settlers pursued agriculture as their primary livelihood. However, after the discovery of rich ore deposits, industrialization swept into the valley. Two brothers, James and Thomas Johnson, began to capitalize upon the valley's industrial potential on the eve of the American Revolution. They bought land at the foot of the Catoctin Ridge and began construction of an iron furnace. Thomas would shortly become one of Maryland's Revolutionary governors. The Johnson furnace was in blast by 1776. Records indicate that their operation produced ammunition for the Continental Army.

Industrialization at Catoctin

The coming of industry at the furnace site resulted in a pattern of settlement in the immediate area which differed significantly from the distended pattern of farmsteads typical of the surrounding area. A village complex with a concentration of specialized workers developed. Charcoal house, casting house, foundry, forge, stables, wagon sheds, saw mills, stores, churches, and workers' houses were all necessary to the iron operation. A number of specialized workers and craftsmen were also necessary. Miners dug the ore. Colliers prepared the charcoal. Fillers charged the furnace. Founders oversaw the casting of the iron. The foreman of the operation was the iron master. Blacksmiths and other skilled workers abounded also.

The Johnson operation continued successfully through about 1795, then was apparently idle until 1803. Between 1803 and 1811 substantial improvements were made. But financial crises after that time led to a long period of instability. In 1831 John Brien purchased the complex and modernized it. In 1856 a new owner erected a second furnace stack. Like the original Johnson stack, the new one was 33 feet high. Unlike the Johnson stack, which was fired by a water powered bellows, the new one was fired with steam operated machinery. The new stack was affectionately named "Isabella" and is the stack still standing today. The Johnson stack was continued in blast until 1890, by which time it was so outdated that the owners shut down and dismantled it.

"Isabella" was a sophisticated furnace that required a steam engine and engine house, a hot air oven to provide a hot blast, and other support facilities. In one respect it, too, was outdated at the time it was built. New methods in iron technology were being developed which allowed the use of coal to smelt the ore. No coal was available in the Catoctin region, so "Isabella" as an old fashioned charcoal furnace was less efficient to operate. "Isabella" was, nevertheless, in continuous blast until 1893.

In 1873 a third stack was built about 140 feet south of "Isabella." The newcomer was named "Deborah." It was a steam and water powered, coal fired furnace with a daily capacity of 35 tons of pig. It was built in hopes of reviving the failing Catoctin Furnace complex, and it may have helped stave off the inevitable day of reckoning. But in 1903 the whole complex was forced to shut down due to its unprofitability. "Deborah" was dismantled two years later.

Catoctin Furnace was the victim of changing technology. Industrialization, which spawned the operation, also passed it by. Built at a time when charcoal was used to fuel iron furnaces, Catoctin was blessed with an unlimited supply of forest timber to produce charcoal. But with the perfection of cheaper and more efficient methods utilizing coal, it suddenly became antiquated. "Deborah" was a coal fired furnace, but the lack of a railroad nearby to ship in coal and to ship out the finished product made it too expensive to operate profitably.

Iron furnaces of the eighteenth and nineteenth centuries functioned on fairly simple principles. The furnace itself was a truncated pyramid of stone built into or near a hill. Fillers carried iron ore, charcoal or coal, and limestone across a bridge connecting the hill and the stack, near the stack's upper opening. They dumped the charge into the furnace tunnel head where it combined with heat and blasted air. The heat caused interaction between the ore and limestone thus smelting out the iron.

Pig Iron

The impurities, or "slag," floated to the top of the mixture and was skimmed off. The air blast was provided by a bellows or by geared machinery attached to either a water wheel or steam engine for power. The Johnson's stack was blasted with unheated or "cold" air. "Isabella" and "Deborah" had their blast air pre-heated giving a "hot" blast, which was more efficient. Built against the stack was the casting shed where molten iron was cast off by the founder into sand molds shaped something like a sow with suckling piglets, hence the term "pig iron."

Pig iron was either hammered mechanically into blooms or bar iron which blacksmiths then reheated and shaped into a variety of useful tools, or it was remelted and cast into hollow wares such as pots and kettles.

"Isabella" is the focal point of the Catoctin Furnace remains. The 1858 casting shed has been reconstructed next to it. Behind the stack and shed and extending southward is the stone retaining wall which is believed to have been built in the late 19th century when the furnace was on hard times. The furnace had operated for 100 years without the wall. The wall is thus thought to have been built more as a make-work project for the otherwise idle iron workers. The original stack built by the Johnsons is believed to have stood close to the middle of the retaining wall. It is possible that some of the stone in the wall was taken from the first stack since the wall was built about the time the first stack was dismantled.

Running northwardly from the complex is a short tramway constructed in the mid-19th century to connect the furnace with ore banks a bit over a mile away. These banks are just west of U.S. Route 15. Other ore banks are along the west edge of Route 15 immediately west and southwest of the furnace. Just south of the furnace on Maryland Route 806 are stone and log houses originally occupied by company workers. These houses are now privately owned and the privacy of the residents should be respected. Pick up a self-guided walking tour brochure of the Catoctin Furnace ruins at the park visitor center.

The Friends of Cunningham Falls State Park

The Friends of Cunningham Falls State Park supports park run programs and on-site improvements through financial contributions and by volunteering time to sponsor educational efforts. For additional information contact:

Friends of Cunningham Falls State Park, Inc.
14039 Catoctin Hollow Road
Thurmont MD 21788