The vast virgin forests of Laurel Hill were doomed by the advent of specialized logging railroads and geared locomotives. Shay, Heisler, and Climax engines, often called stem-winders, moved along previously inaccessible shallow creeks and up and down steep valleys. Powerful but slow and unusually stable on winding narrow gauge rail lines, they hauled the region's harvested trees over irregular temporary track to local sawmills. America's early industries consumed timber in colossal quantities, and coal mines, railroads, tanneries, and urban centers like Pittsburgh all demanded more wood. Within a few decades, the forests here had been completely expended, worked through local sawmills, and sent on to support a growing nation.