Isabella Furnace was a collection of

blast furnace A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being "forced" or supplied above atmospheric ...

s built in 1872 in

Etna, Pennsylvania Etna is a Borough A borough is an administrative division in various English-speaking countries. In principle, the term ''borough'' designates a self-governing walled town, although in practice, official use of the term varies widely. Hist ...

, across the

Allegheny River The Allegheny River ( ) is a long headwater stream of the Ohio River in western Pennsylvania and New York (state), New York. The Allegheny River runs from its headwaters just below the middle of Pennsylvania's northern border northwesterly into ...

from

Pittsburgh Pittsburgh ( ) is a city in the Commonwealth (U.S. state), Commonwealth of Pennsylvania, United States, and the county seat of Allegheny County, Pennsylvania, Allegheny County. It is the most populous city in both Allegheny County and Wester ...

. The furnaces were built by Pittsburgh-area manufacturers (Lewis Dalzell & Co; J. Painter & Sons; Graff, Bennet & Co; Spang, Chalfant & Co; Henry Oliver of Oliver Brothers & Phillips; William Smith) who were dependent on pig iron. They incorporated as the Isabella Furnace Company and built two furnaces, later adding a third. The first two furnaces were 75 feet high, one with a capacity of 12,800 cubic feet and the other 14,000 cubic feet. They were built following the designs of modern English furnaces, among the first in the United States and among the largest at the time. Isabella Furnace Co. also built in Spring 1872 its 200-oven, 600-acre coke works for the furnace in Coketown (now Cokeville) near the terminus of the W.P.R.R., 60 miles to the East. Isabella Furnace was named after two women: Isabella Herron, the sister of one of the members of owners Spang, Chalfant & Co. and Isabella Crowther, daughter of the furnace's lead engineer, Cyril W. Crowther. At the same time, The

Carnegie Steel Company Carnegie Steel Company was a steel-producing company primarily created by Andrew Carnegie and several close associates to manage businesses at steel mills in the Pittsburgh, Pennsylvania area in the late 19th century. The company was forme ...

was building its

Lucy Furnace Lucy Furnace was a pair of blast furnaces in Pittsburgh, Pennsylvania, on the Allegheny River in Lawrenceville. The furnaces were part of the Carnegie Steel Company, with the first furnace erected in 1871 by brothers Andrew and Thomas M. Carnegi ...

one mile down the Allegheny, and both the Lucy and Isabella went into blast around the same time in the summer of 1872. The Lucy and Isabella maintained a fierce rivalry, racing to outproduce each other. The rivalry lasted until Lucy was dismantled in 1937. In 1901,

acquired the Isabella. The next year, much of the plant was replaced with more modern equipment. James Gayley developed the dry-air blast technique at Isabella Furnace and the

Edgar Thomson Steel Works The Edgar Thomson Steel Works is a steel mill in the Pittsburgh area communities of Braddock and North Braddock, Pennsylvania, United States. It has been active since 1875. It is currently owned by U.S. Steel and is known as Mon Valley Works – E ...

between 1885 and 1904. The discovery reduced the cost of a ton of pig iron by $0.50 to $1.00 and made it possible to produce uniform quality metal regardless of weather. It was first put into operation at the plant on August 11, 1904. In the week prior to its introduction, Isabella averaged 358 tons of pig iron daily, consuming 2,147 pounds of coke; in the following week it averaged 447 tons with a coke usage of 1,726 pounds. Isabella Furnace 1880

By 1948, the plant was no longer producing any iron; its furnaces repurposed exclusively to produce

ferromanganese Ferromanganese is a ferroalloy with high manganese content (high-carbon ferromanganese can contain as much as 80% Mn by weight). It is made by heating a mixture of the oxides MnO2 and Fe2O3, with carbon (usually as coal and coke) in either a bla ...

, an important deoxidizing alloy in steelmaking. Using 10 million gallons of water a day, the furnaces produced about 210 tons of ferromanganese. Isabella ceased operation in August 1953. It was scheduled to be shut down at least a decade earlier, but

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

and the

Korean War , date = {{Ubl, 25 June 1950 – 27 July 1953 (''de facto'')({{Age in years, months, weeks and days, month1=6, day1=25, year1=1950, month2=7, day2=27, year2=1953), 25 June 1950 – present (''de jure'')({{Age in years, months, weeks a ...

produced unexpected demand for steel.

References

{{reflist Ironworks and steel mills in Pennsylvania Industrial buildings and structures in Pennsylvania Industrial buildings completed in 1872 Blast furnaces in the United States U.S. Steel 1872 establishments in Pennsylvania