I stood amid a group of eight tourists on the ground level, around a brightly lit, U-shaped counter. A gangly Park Service employee was giving us a brief history of the Post Office. He mumbled into a microphone in a barely intelligible, nasal voice. The man next to me was taping him with a video camera. After his speech we were ushered into a glass elevator and began our ascent to the tower base. The checkerboard floor of the Pavilion fell away rapidly as we rose higher. A little girl near me said to her father, “Daddy, if we fell now, we’d be dead, right?” An older woman who already looked a little frightened touched her collar and laughed nervously. The doors opened and we walked out to a circle of white and red ropes that rang the Congress Bells. A rotund guide informed us that the bells, a gift from Great Britain, were rung on the opening and closing days of Congress, and on all national holidays. The only other instances when they were rung, she said, were in honor of the Challenger’s crew, and “when the Redskins won the Super Bowl.”