Cornwall Iron Furnace - Overview

Overview

Cornwall Iron Furnace was one of many ironworks that were built in Pennsylvania over a sixty-year period, from 1716-1776. There were at least 21 blast furnaces, 45 forges, four bloomeries, six steel furnaces, three slitting mills, two plate mills, and one wire mill in operation in Colonial Pennsylvania.

The furnaces at Cornwall Furnace went through two stages of technology. Peter Grubb was born in Delaware about 1702 and settled in what is now Lebanon County in 1734. He bought about 300 acres (1.2 km2) of magnetite rich land. Grubb also noticed that his land had the other natural resources needed to produce iron. Namely, vast stands of timber for the production of charcoal, running water to operate the bellows, and an ample supply of limestone needed to add flux to the smelting furnaces. Grubb's plans were further helped by the fact that the magnetite at Cornwall was either very close to or on the surface of his land. He was ready to venture into the iron business and set about the task of building an iron "plantation". These centers of iron production were usually located well away from the heavily cleared farmlands and were nestled in the Ridge and Valley section of Pennsylvania. Grubb constructed his furnaces, first a bloomery and later the more modern charcoal-fired blast furnace and the support buildings and mill village that was needed to house his workers. He named his operation Cornwall because his father, John Grubb had come from Cornwall, UK in 1677. Cornwall Iron Furnace was an excellent fit for the agricultural based economy of the Thirteen Colonies. Iron was needed to make into tools, nails and weapons. The official policy of Great Britain frowned on manufacturing in the colonies, but England was no longer able to produce the needed iron for its needs let alone the needs of the colonists. In fact England had become dependent on importing iron from Sweden.

Peter Grubb was not really an ironmaster, but a builder. In 1745 he leased the ironworks to a consortium, Cury and Company, for 25 years and returned to Wilmington. The consortium continued the operation, with ownership passing to Peter's sons, Curtis and Peter Jr., after his death in 1754. The brothers took over the operation in 1765 and ran it quite successfully until the late 1780s. Curtis operated the Cornwall Furnace and lived on site; c1773 he built the original 19 rooms of the mansion that still stands prominently next to the property. Peter Jr. ran a forge at Hopewell, refining the pig iron produced by the furnace into more valuable bar iron. The ironworks were major suppliers to the Revolutionary War effort, and George Washington once visited to inspect the operation. Unfortunately for the Grubb family, as described in Curtis Grubb's biography, they were unable to retain control of the operation after Curtis' marriage in 1783. Most of the Grubb's holdings gradually fell into the hands of Robert Coleman, culminating in 1798. Coleman's son, William, was named manager of Cornwall Furnace and lived in the mansion; in 1865 the Colemans remodeled it into the 29 room structure known today as Buckingham Mansion.