With a Listing of National, State, and Private Sites Related

to the Pennsylvania Iron Industry and Open to the Public




Gerald G. Eggert


Pennsylvania History Studies No. 25

The Pennsylvania Historical Association

c/o Penn State ‑ Harrisburg

Crags Building, 777 W. Harrisburg Pike

Middletown, PA 17057‑4898


Copyright 1994

Pennsylvania Historical Association


Printed in the U.S.A. by

Plank's Suburban Press, Inc.

Camp Hill, Pennsylvania 17011


This publication contains references to David Thomas and to George Crane and the roles played in the development of the use of anthracite coal in iron-making.



The Shift to Anthracite‑fueled Furnaces


Although Pennsylvania east of the Alleghenies had almost no bituminous (soft) coal, most of the world's anthracite (hard) coal lay beneath some 484 square miles of that region. Hard coal's use was long delayed because of the difficulty of getting it to burn. Some questioned whether this type of "stone" coal, as it was called, would burn at all. It was indeed combustible, but only if first heated to a high temperature. Once afire, it gave off such intense heat that it burned out ordinary grates and fireboxes. Blacksmiths were among the earliest users of hard coal because their operations required no special equipment. Once home cooking and heating stoves were equipped with modified grates, anthracite became a popular domestic fuel, and from 1815 onward was commonly used to fire the boilers of steamboats and locomotives. Refinery forges could not use anthracite because its high sulfur content contaminated the iron. The development of rolling mills equipped with reverberatory puddling furnaces, as already noted, solved that problem; by 1848 no fewer than 18 rolling mills in southeastern Pennsylvania boasted puddling furnaces fueled with anthracite.


The use of anthracite to fuel iron furnaces came with a growing realization that charcoal limited any further advances in smelting. The problem was two-fold. Most obvious was that diminishing forests reduced the availability of charcoal while advancing its cost. Anthracite, on the other hand, existed in seemingly unlimited supply in southeastern Pennsylvania and offered great cost advantages. Production of one ton of pig iron, for example, took from 180 to 200 bushels of charcoal, which at five cents per bushel meant a cost of from $9 to $10. The same ton of pig, if made with anthracite, used two tons of coal, which at $2.50 per ton totaled $5, a savings of approximately one‑half.


Less recognized was that charcoal-fueled furnaces could not be enlarged to increase output. The reason was charcoal's high frangibility, that is, it broke up easily and tended to pulverize under pressure. Crushed charcoal would not properly fuel a furnace because it clogged the flow of air from the blast. If too large a furnace were constructed, the increased weight of its contents broke up the charcoal and smothered combustion. The only way to increase the overall output of charcoal iron was to erect additional furnaces.


The growing demand for iron sparked interest in anthracite fueled furnaces. A sprinkling of experiments in the first two decades of the nineteenth century, however, came to naught. Promoters of anthracite next tried special inducements for practical results. In 1825 the Franklin Institute of Philadelphia offered a gold medal to whoever first manufactured more than 20 tons of pig using only hard coal. During the 1830s the Lehigh Coal and Navigation Company promised free waterpower and reduced coal prices to whatever company initially developed a successful process for smelting with anthracite.


Near the end of the decade, Nicholas Biddle and associates set up a $5,000 prize for the first person to keep an anthracite furnace in blast for three months. Even so, furnaces specifically designed to burn anthracite failed at Mauch Chunk in 1826 and Lebanon in 1827.


In fact, anthracite could not be used for smelting until the furnace blast was made stronger and heated before use. These techniques developed across the Atlantic but quickly spread to the United States. The first grew out of a failure in eastern France in 1826‑27 to smelt iron with anthracite and coke, using a cold blast. When ignited, the fuel broke up, blocking the blast. It was suggested that perhaps a stronger blast would have succeeded. Both European and American ironmasters, some using charcoal, others anthracite mixed with coke, found a more forceful blast helpful. A furnace at Catasauqua, Pennsylvania considerably increased its output by stepping up its blast from 3/4ths of a pound to 10 pounds per square inch. To get stronger, more uniform blasts, American ironmasters after 1850 shifted from water wheels to steam engines to produce them.


Meanwhile experiments with heated‑air blasts got underway. Scotsman James B. Neilson, seeking to improve the efficiency of coke-fired furnaces, devised a machine for heating air to 300 degrees Fahrenheit before blowing it into the furnace. He patented the process in 1828 even as he continued experiments to improve it. By 1835, thirty‑seven furnaces in England and Scotland were using hot blast. Meanwhile in the United States, the Scranton Brothers introduced the hot blast at their Oxford Furnace in New Jersey in 1834. The hot blast, produced by using waste heat from the stack, both reduced fuel consumption and allowed expansion of the size and capacity of furnaces. By 1849 more than half of the charcoal iron furnaces in eastern Pennsylvania and the Juniata region (66 of 125) had shifted to hot blast. On average such furnaces were a little larger in size than their cold blast counterparts, employed one-fifth more workers, and increased their capacities by more than 30 percent. Ironmasters of Western Pennsylvania adopted the hot blast somewhat later.


Credit for mastering the actual smelting of iron with anthracite must be shared among several Americans and Britons working both here and abroad. In 1831, for example, Frederick W. Geissenhainer experimented with anthracite fuel and a hot blast in a small furnace in New York City. It worked well and he patented the process in 1833. Three years later he built Valley Furnace in Schuylkill County where for two months he made anthracite iron until his machinery broke down. He died in 1838 before he could get improved equipment in place.


Also during the 1830s, George Crane, the English owner of three furnaces at Yniscedwin, near Swansea in Wales, experimented with anthracite. Costs of the long haul of his usual fuel, coke, were high. Inasmuch as his furnaces stood on the only deposit of anthracite in Wales, he and his Welsh ironmaster, David Thomas, tried to find a practical way to use it. After several years they concluded that perhaps the solution lay in a hot blast. Thomas visited a facility equipped with Neilson's heating device, obtained a license to use it, and returned to Yniscedwin. There he employed a hot blast in an anthracite‑fueled furnace to produce high quality iron in 1837.


At that very time, a nephew of a founder of the Lehigh Coal and Navigation Company in America was studying railroad iron in England. Learning of the Crane-Thomas experiments, he reported to his uncle, who in turn passed the information on to the Lehigh firm. That company, by chance, was itself experimenting with anthracite. Building a hot blast anthracite furnace near Mauch Chunk in 1838, they successfully produced iron for several months, putting out some 100 tons of anthracite iron. For reasons not fully explained, they halted production. Dispatching an agent to Wales, the firm induced Thomas to come to the United States to work for them. After placing orders for machinery in Britain, Thomas crossed the Atlantic and directed construction of what became the newly named Lehigh Crane Iron Company's first anthracite furnace. It went into blast on July 4, 1840 and continuously produced iron until 1879.


However, before Thomas could fire his furnace, Burd Patterson of Pottsville blew in an anthracite furnace of his own. Patterson in 1837 had persuaded William Lyman of Boston to build Pioneer Furnace for him. Lyman in turn employed Benjamin Perry, a Welshman experienced in the use of anthracite, to put it in blast when it was completed in 1839. Its successful functioning from October 1839 into January 1840 allowed Lyman to collect the $5,000 award offered by Biddle. Perry, meanwhile, went on to complete and blow in two other anthracite furnaces prior to Thomas's successful firing: Roaring Creek Furnace in Montour County (May 18, 1840) and Columbia Furnace at Danville July 2, 1840). Two others also preceded Thomas: Biddle, Chambers & Company blew in an anthracite furnace in Montour County in April and William Firmstone another at Phoenixville on June 17, 1840.


Although in the end Thomas was far from first in America, his furnace endured longest and served as a model for those that followed. By 1841, nine anthracite‑fired blast furnaces were in operation in Pennsylvania. By decade's end there were 55 and that year, 1849, they produced 43 percent of the State's actual output of iron. The development of anthracite iron production at Danville was particularly impressive. Four anthracite blast furnaces arose there between 1839 and 1841. In 1844 construction began on a large rolling mill, one with 26 puddling furnaces and two trains of rolls. The mill in October 1845 turned out the first "T" rail made in the United States. Danville for years was home of the nation's largest rail mill, which by 1856 annually produced 20,000 tons of rails.


As matters turned out, not only was anthracite cheaper to use, it was also a sturdier fuel, less apt to pulverize under the pressure of weight. This enabled ironmasters to erect larger furnaces. On average in 1849, the boshes of anthracite furnaces were half again as wide as those of hot blast charcoal furnaces (12 feet as compared with 8 feet), their stacks were 6 feet taller (36 feet compared to 30, with seven stacks reaching 45 feet), they employed an average of 92 workmen compared to 72, and their average output was three times greater than that of hot blast charcoal furnaces (2,799 tons per year compared with 936 tons). All were located in the 13 counties making up or surrounding the anthracite fields. Most were in urban centers such as Allentown, Bloomsburg, Catasauqua, Columbia, Conshohocken, Danville, Easton, Harrisburg, Lebanon, Light Street, Mauch Chunk (now Jim Thorpe), Pottsville, Reading, Scranton, and Wilkesbarre. To those urban furnaces iron ore, limestone, and anthracite moved by canal or rail.


Furnaces built after 1850 differed in other ways from their charcoal‑burning predecessors. Brick and sometimes even iron replaced the stone masonry of furnace stacks. Inside, sandstone linings gave way to special firebrick. Boshes became steeper, and instead of a single tuyere to carry the blast to the crucible, several became the rule. And, of course, steam power largely replaced water power. By 1860, when total American production of iron was five times greater than only three decades earlier, 57 percent came from furnaces fueled with anthracite or a combination of anthracite and coke.


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Rev. February 2010