Cumberland county, which forms the eastern portion of the great Cumberland Valley, is made up, as we ordinarily know it, of three geological formations, viz: the slate on the north, the limestone in the center, and the sand or pinelands on the south. It is drained lengthwise by the Conodoguinet and the Yellow Breeches creeks.
The factors that gave rise to the iron industry in Pennsylvania are detailed in many studies of early settlement and industrial progress. Both William A. Sullivan in his Industrial Worker in Pennsylvania and Arthur Bining's Pennsylvania Iron Manufacture in the Eighteenth Century describe the rich, natural resources of the early colony and the influx of wage earners from the Old World as the perfect setting for industrial growth and development.