|Name Thomas Walter|
|Born September 4, 1804 (1804-09-04) Philadelphia, Pennsylvania|
Projects United States Capitol dome, Philadelphia City Hall
Died October 30, 1887, Philadelphia, Pennsylvania, United States
Buildings Moyamensing Prison, Girard College
Structures United States Capitol, Girard College, Philadelphia City Hall, Andalusia, Chester County Courthouse
Similar People Benjamin Henry Latrobe, William Thornton, Charles Bulfinch, Robert Mills, Edward Clark
Michael Lewis on The Architect of Philadelphia City Hall
Thomas Ustick Walter (September 4, 1804 – October 30, 1887) was an American architect, the dean of American architecture between the 1820 death of Benjamin Latrobe and the emergence of H.H. Richardson in the 1870s. He was the fourth Architect of the Capitol and responsible for adding the north (Senate) and south (House) wings and the central dome that is predominately the current appearance of the U.S. Capitol building. Walter was one of the founders and second president of the American Institute of Architects.
- Michael Lewis on The Architect of Philadelphia City Hall
- Early life
- The US Capitol and its dome
- Other honors
Born in 1804 in Philadelphia, Walter was the son of mason and bricklayer Joseph S. Walter and his wife Deborah.
Walter received early training in a variety of fields including masonry, mathematics, physical science, and the fine arts. At 15, Walter entered the office of William Strickland, studying architecture and mechanical drawing, then established his own practice in 1830.
Walter was commissioned by Spruce Street Baptist Church to design its new building at 418 Spruce Street. The 1829 building is today home to the Society Hill Synagogue.
Walter's first major commission was Moyamensing Prison, the Philadelphia County Prison. Designed as a humane model in its time, the prison was built between 1832 and 1835.
Walter also designed the First Presbyterian Church of West Chester, which opened its doors in January 1834.
In March 1834, the Walter-designed Wills Eye Hospital opened on the southwest corner of 18th and Race Streets in Philadelphia (opposite what is now Logan Circle).
He first came to national recognition for his design of Girard College for Orphans (1833–48) in Philadelphia, among the last and grandest expressions of the Greek Revival movement.
Walter also designed mansions, banks, churches, the hotel at Brandywine Springs, and courthouses. In 1836, he designed the Bank of Chester County at West Chester, Pennsylvania; a decade later, he designed the 1846 Chester County Courthouse in Greek Revival style. He designed the St. James Episcopal Church (Wilmington, North Carolina) which opened in 1840. In Lexington, Virginia, he designed the Lexington Presbyterian Church in 1843. The same year he designed the Chapel of the Cross in Chapel Hill, North Carolina. In Norfolk, Virginia, he designed the Norfolk Academy in 1840. The Tabb Street Presbyterian Church was erected at Petersburg, Virginia in 1843.
It has also been suggested that Walter designed the Second Empire-styled Quarters B and Quarters D at Admiral's Row in Brooklyn, New York.
Among the notable residences designed by Walter were his own home, located at High and Morton Streets in the Germantown section of Philadelphia ; the Nicholas Biddle estate Andalusia; Inglewood Cottage; and St. George's Hall, residence of Matthew Newkirk, president of the Philadelphia, Wilmington & Baltimore Railroad (PW&B). Walter also designed the Garrett-Dunn House in Philadelphia's Mt. Airy neighborhood , which was destroyed by fire after being struck by lightning on August 2, 2009. 
Among his smaller designs was the 1839 Newkirk Viaduct Monument, commissioned by the PW&B to mark the completion of the first rail line south from Philadelphia.
The U.S. Capitol and its dome
The most famous of Walter's constructions is the dome of the U.S. Capitol. By 1850, the rapid expansion of the United States had caused a space shortage in the Capitol. Walter was selected to design extensions for the Capitol. His plan more than doubled the size of the existing building and added the familiar cast-iron dome.
There were at least six draftsmen in Walter's office, headed by Walter's chief assistant, August Schoenborn, a German immigrant who had learned his profession from the ground up. It appears that he was responsible for some of the fundamental ideas in the Capitol structure. These included the curved arch ribs and an ingenious arrangement used to cantilever the base of the columns. This made it appear that the diameter of the base exceeded the actual diameter of the foundation, thereby enlarging the proportions of the total structure.
Construction on the wings began in 1851 and proceeded rapidly; the House of Representatives met in its new quarters in December 1857 and the Senate occupied its new chamber by January 1859. Walter's fireproof cast iron dome was authorized by Congress on March 3, 1855, and was nearly completed by December 2, 1863, when the Statue of Freedom was placed on top. He also reconstructed the interior of the west center building for the Library of Congress after the fire of 1851. Walter continued as Capitol architect until 1865, when he resigned his position over a minor contract dispute. After 14 years in Washington, he retired to his native Philadelphia.
In the 1870s, financial setbacks forced him to come out of retirement, and he worked as second-in-command when his friend and younger colleague John McArthur, Jr. won the competition for Philadelphia City Hall. He continued on that vast project until his death in 1887.
For their architectural accomplishments, both Walter and Benjamin Latrobe are honored in a ceiling mosaic in the East Mosaic Corridor at the entrance to the Main Reading Room of the Library of Congress.
Walter's grandson, Thomas Ustick Walter III, was also an architect; he practiced in Birmingham, Alabama, from the 1890s to the 1910s.