National Geographic : 1966 Jul
Invention factory: For 44 years Thomas Alva Edison worked in this laboratory at West Or ange, New Jersey, developing fluorescent lamps, motion-picture cameras, and other products of his genius. The National Park Service main tains it just as Edison left it at his death in 1931. Stage for history, the restored Senate Cham ber of Congress Hall in Philadelphia sees early lawmaking reenacted by members of the city's bar association. Independence National His torical Park preserves the buildings in which the United States was born.