In the center of town, the Mercer Museum, opened in 1916, displays Mercer's collection of tools, including more than 50,000 objects from before the steam age. An archaeologist, Mercer worried that the rapid advance of industrialization would wipe out evidence of preindustrial America. Consequently, from 1895 to 1915 he scoured the back roads of eastern Pennsylvania, buying folk art, tools, and articles of everyday life to display in another of his concrete castles. In what amounts to a six-story attic, log sleds, cheese presses, fire engines, boats, and bean hullers are suspended from walls and ceilings and crammed into rooms organized by trade or purpose. Interactive activities, like downloadable scavenger hunts , and a special audio-guide channel keep children amused. A new wing includes a climate-controlled gallery that allows for changing exhibits, including traveling shows and items from the collection that couldn't otherwise be displayed, such as a lock of George Washington's hair. Scholars can take advantage of the library and reading room, open to the public Tuesday through Saturday.