dome, through which is seen The Apotheosis of Washington painted on a shell suspended from the supporting ribs, which also support the visible exterior structure and the tholos that supports the Statue of Freedom, a colossal statue that was raised to the top of the dome in 1863. The statue invokes the goddesses Minerva or Athena. The cast iron for the dome weighs . The dome's cast iron frame was supplied and constructed by the iron foundry Janes, Fowler, Kirtland & Co. Later expansion When the Capitol's new dome was finally completed, its massive visual weight, in turn, overpowered the proportions of the columns of the East Portico, built in 1828. In 1904, the East Front of the Capitol building was rebuilt, following a design of the architects Carrère and Hastings, who also designed the Russell Senate and Cannon House office buildings. In 1958, the next major expansion to the Capitol started, with a extension of the East Portico. In 1960, two years into the project, the dome underwent a restoration. A marble duplicate of the sandstone East Front was built from the old Front. In 1962, a connecting extension repurposed what had been an outside wall as an inside wall. In the process, the original sandstone Corinthian columns were removed and replaced with marble. It was not until 1984 that landscape designer Russell Page created a suitable setting for them in a large meadow at the U.S. National Arboretum in northeast Washington as the National Capitol Columns, where they were combined with a reflecting pool into an ensemble that reminds some visitors of the ruins of Persepolis, in Persia. Besides the columns, two hundred tons of the original stone were removed in several hundred blocks. These were first stored on site at the Capitol and then in an unused yard at the Capitol Power Plant until 1975. That year, the power plant was renovated and expanded in accordance with legislation passed in 1970, and the stones fell to the Commission on the Extension of the United States Capitol. As this body was long-defunct, responsibility for the material passed to the House and Senate office building commissions. These commissions then arranged for the National Park Service to store the debris at the back of a NPS maintenance yard in Rock Creek Park. With the permission of the Speaker of the House, the United States Capitol Historical Society has periodically mined