The Ranger greeted the two dozen visitors who had shown up for the two o’clock tour.  When he had their attention, he began.

"The beauty of this place is compelling, with large green trees, the Shenandoah River behind me flowing into the Potomac River, and the Loudon Heights and Maryland Heights towering above.  In 1860 the picture is somewhat different.  Look anywhere around you and imagine a building, you are probably right.  The a...