UNITED STATES - Dec 19: Constantino Brumidi's painting of the 'Apotheosis of Washington' is shown on the ceiling of the U.S. Capitol's rotunda during a media tour December 19, 2013 in Washington, DC.
When the U.S. Capitol dome was built in the 1860s, cast iron was the high-tech building material of its day, lighter and easier to erect than stone, more fireproof than wood. But if the people’s ...