United States Capitol

===Capitol dome===
{{Main|United States Capitol dome}}
[[File:LincolnInauguration1861a.jpg|thumb|left|The inauguration of [[Abraham Lincoln]] in 1861, with the Capitol dome still under construction]]
The 1850 expansion more than doubled the length of the United States Capitol; it dwarfed the original, timber-framed, copper-sheeted, low dome of 1818, designed by [[Charles Bulfinch]] which was no longer in proportion with the increased size of the building. In 1855, the decision was made to tear it down and replace it with the "[[wedding-cake style]]" cast-iron dome that stands today. Also designed by [[Thomas U. Walter]], the new dome would stand three times the height of the original dome and {{convert|100|ft}} in diameter, yet had to be supported on the existing masonry piers.

Like [[Jules Hardouin-Mansart|Mansart]]'s dome at [[Les Invalides]] in [[Paris]] (which he had visited in 1838), Walter's dome is double, with a large [[Oculus (architecture)|oculus]] in the inner 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 [[wikt:tholos|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]].<ref>{{Cite web|url=https://picturinghistory.gc.cuny.edu/thomas-crawford-statue-of-freedom-1855-63/|title = Picturing US History - Thomas Crawford, Statue of Freedom, 1855-63}}</ref><ref>{{Cite web|url=https://www.aoc.gov/explore-capitol-campus/art/statue-freedom|title = The Statue of Freedom &#124; Architect of the Capitol}}</ref> The [[cast iron]] for the dome weighs {{convert|8909200|lb|kg}}.<ref>{{cite web|title=Capitol Dome|url=https://www.aoc.gov/capitol-buildings/capitol-dome|publisher=Architect of the Capitol|access-date=May 2, 2017}}</ref> The dome's cast iron frame was supplied and constructed by the iron foundry [[Adrian Janes|Janes, Fowler, Kirtland & Co.]]<ref>{{Cite web|last=Terrell|first=Ellen|date=2015-05-20|title=The Capitol Dome: Janes, Fowler, & Kirtland Co. {{!}} Inside Adams: Science, Technology & Business|url=https://blogs.loc.gov/inside_adams/2015/05/the-capitol-dome-janes-fowler-kirtland-co/|access-date=2021-08-24|website=Library of Congress Blogs }}</ref> The thirty-six Corinthian columns that surround the base of the dome were provided by the Baltimore ironworks of [[Robert Poole (industrialist)|Poole & Hunt.]]<ref>{{Cite book |last=Swett |first=Steven |title=The Metalworkers: Robert Poole, His Ironworks, and Technology in 19th Century America |publisher=Baltimore Museum of Industry |year=2022 |isbn=978-0-578-28250-3 |location=Baltimore, Maryland |pages=85–122}}</ref>