National Geographic : 1987 Jun
Built to last, the tightly crafted stones of lock one (below left) belie the pitfalls faced by superintendentsduring its construction.Labor was a major headache. Indentured servants showed a penchantfor running away. Recalcitrants' heads and eyebrows were shaved on recapture. Finally, black slaves were rentedfrom nearby plantations. Professionalmasons left their individualmarks (left) on the locks' stones. Their skill is ex hibited also at the Capitol,the White House, and the federal fort in New York Harboron which the Statue of Liberty was erected-all bear some of the same mason's marks. Years of neglect allowed the erosion of most of the Great Falls canal-and-lockcomplex. A park cultural-preservation team wrestles with a stone dis placed by tree roots (below). A mandate to preserve the park's historic structureshas led to protestsfrom local bird watchers, who object to the removal of trees in a prime birding site on the outskirts of Washington.