Purchased from a large tract of land belonging to William Penn, William Allen and Joseph Turner started their iron works here in 1760. Slaves and indentured servants were employed to extract and process iron ore to produce fine grade iron. The iron mined here was esteemed as being excellent for production into steel. The mines, forges and furnaces at Andover were confiscated by an Act of the Continental Congress on January 15, 1778 as its owners were loyal to the British Crown. George Washington's encampment at Morristown, New Jersey, was in part to protect these works from falling into British Control. The Iron Master's House, occupied by John Hackett, Allen and Turner's manager, sits above the ravine in which the iron works was located.