Donora’s blast furnaces, as well as the Carrie blast furnaces in Homestead, were enormously complex beasts. The processes they used to produce raw steel were carefully managed by teams of engineers and highly skilled workers. But the basic processes have been around for centuries.

A blast furnace is essentially a container for chemical reactions. It is shaped somewhat like an Erlenmeyer flask, with a wide base and narrow top. Heated air is forced into the base of the “flask,” while various solid elements are fed into the top. Those elements include iron ore, limestone, and coke, the three main ingredients needed to make steel.

Working at a blast furnace was always dangerous, though not necessarily for the same reason. The first blast furnace in the United States was built in a tiny Virginia settlement called Falling Creek, along the James River a few miles south of Richmond. Englishman John Berkeley had been overseeing the construction of the furnace in 1622 when a group of Native Americans, led by a man named Opechancanough, suddenly attacked the settlement.

Opechancanough had been chief of a covey of about thirty-two tribes, called the Powatan Confederacy, whose members all spoke Algonquian, a language responsible for a wide variety of words in today’s English, including moose, raccoon, hickory, squash, succotash, moccasin, tomahawk, and toboggan. The Powhatans, also known as Virginia Algonquian, were initially led by Opechancanough’s brother, Powhatan, who had maintained a degree of peace between his tribes and the settlers. When Powhatan died in 1618, his brother became chief.

Opechancanough—which means, rather ironically, “He Whose Soul is White”—despised English settlers, in particular John Smith, he of Jamestown fame. Smith had captured Opechancanough’s father, Chief Powhatan, at gunpoint several years earlier. From his ascent to chief until his death in 1644 Opechancanough conducted a great many raids on white settlements, including a coordinated wave of simultaneous attacks on March 22, 1622. Opechancanough and his men decimated a number of settlements and slaughtered everyone they could find. Somewhere between 300 and 500 settlers died over a span of just a few hours. Among the first sites to be attacked was Falling Creek. Berkeley and twenty six other settlers perished in the raid, and the furnace was destroyed.

The Falling Creek furnace might have been operational for a time, but never functioned to full capacity. It would be nearly a quarter-century before Saugus Iron Works, along the Saugus River ten miles north of Boston, manufactured the first product from a successfully operating blast furnace. It was a three-legged, softball-sized cooking pot, similar to a Dutch oven, and is known today as the Saugus Pot.

As northern settlers began moving south, they looked for significant iron ore deposits along the way. When they found them, they constructed a blast furnace nearby. The Hopewell Furnace in Elverson, Pennsylvania, eighteen miles northwest of Valley Forge, was erected sometime around 1771 and supplied 115 large cannon for the Continental Navy. It also provided the ten-inch mortar shells used in the Yorktown battle, the final major battle of the Revolutionary War.

The Alliance Furnace, the first blast furnace built west of the Allegheny Mountains, stood beside a bend in Jacob’s Creek about two-and-a-half miles east of the Youghiogheny River. Pittsburgher William Turnbull had acquired 300 acres of land, and then he and his partners, John Holker and Peter Marmie, constructed the furnace in 1789, with its first blast occurring in November. The furnace wasn’t terribly efficient and was closed for good in 1802. Only ruins remain today.

A great many blast furnaces were built in Western Pennsylvania after the Alliance Furnace. The table below provides information about early blast furnaces built in Fayette County alone!

If you haven’t visited a blast furnace site, give it a go. And with apologies ahead of time, have a blast!