The time span during which American ironworks used the medieval iron technology brought by settlers from Europe—the Colonial (1607-1776) and Early National (1777-1850) Eras—totaled two-and-a-half centuries. During that period no fewer than a thousand charcoal-fueled, cold-blast iron furnaces were built and operated in the United States, and probably about as many forges. (In 1849 Pennsylvania alone reported having 298 furnaces and 122 forges).  Some were in business less than a year, others for several decades; the overall average being about 10 years.  Principio Furnace, founded in colonial Maryland in 1719 and the Curtin family’s Eagle Iron works running from 1809 to 1922 in Centre County, Pennsylvania, were among a very few in business for more than a century.

Despite essential similarities, these ironworks differed in many ways.  One was by the regions where they were built.  Those in the Chesapeake region (Virginia and Maryland) sprang from English roots and used more servile laborers (black and Indian slaves, white indentured servants.)  Those in the middle region (New Jersey, Delaware and Pennsylvania) had both English and German roots and employed free laborers, though they used indentured and slave labor until those systems became illegal after the Revolutionary War.  Finally, New England’s ironworks grew out of East Anglian English roots and generally used free labor.   Another factor was whether the ironmasters involved were experienced, well financed and knew what they were doing as opposed to ironworks set up by inexperienced, poorly financed opportunists.  Some operated in profitable periods, others at times when the economy doomed them to failure.  Finally there was the mere passing of time during which different personnel would employ different practices, or different terminology for the same operations.

Thus, it must be kept in mind in reading the One-Minute Essays that they are generalizations.  Unless otherwise indicated, they are meant to convey information that in general applies to all the ironworks under discussion.  But of course no ”One-Minute Essay” description of “blowing in” a new furnace, for example, could possibly take into account the exact steps taken, or precise terminology used, or titles given the various tasks at a thousand furnaces over the course of 250 years.  Hopefully, other accounts that you may read on the same topic will tell essentially the same story even if it differs in details. We recommend you look for works in the bibliography for more information.

The essays I contributed have relied heavily on Pennsylvania ironworks, and especially on Roland Curtin’s Eagle Ironworks because I have researched and written extensively on those topics. However, I have attempted to word the items so as to eliminate what I know or suspect to be usages peculiar to Pennsylvania or to Eagle Ironworks. At the same time, wide reading and visits to many sites in different areas, and to ironworks important in other eras, have sharpened my awareness to the problem and obliged me to make this caution.