BUILDING OF THE CAPITOL

In the development of the accepted plans of Dr. William Thornton in the erection of the first unit of the building the previous Supreme Court sectionthree architects were employed-Stephen H. Hallett, George Hadfield, and James Hoban, the architect of the White House. The erection of the southern section of the Capitol, which is now occupied by Statuary Hall, was under the charge of B. H. Latrobe, and in 1807 the House of Representatives, which had previously met in the former Supreme Court section of the Capitol and in a temporary brick building within the walls of the southern wing, known as the Oven, commenced the occupancy of this new legislative chamber. The north wing was finished in 1800 and the south wing in 1811. A wooden passageway connected the two buildings. This condition existed when the interior of both buildings was burned by the British on August 24, 1814.

The work of reconstruction of the damaged interiors was commenced by B. H. Latrobe, who continued the work of restoration until December 1817, when he resigned, and Charles Bulfinch, a prominent architect of Boston, Mass., continued the work of restoration and the erection of the central portion of the building, commencing in 1818 and continuing until its completion in 1829.

During the period of restoration and completion the Congress met, for its first session after the fire, in Blodget's Hotel at Seventh and E Streets, and soon thereafter in a building erected for that purpose on First Street NE., occupying a portion of the site now occupied by the United States Supreme Court Building. They continued this occupancy until 1819, when the capitol was again ready for

occupancy.

The original Capitol as completed was built of Aquia Creek (Va.) sandstone, procured from quarries owned by the Government. This structure was 352 feet 4 inches in length and 229 feet in depth. The central portion was surmounted by a low dome, and the sandstone interior was unchanged when the new dome was erected in a later period. The cost of this original building, including the grading of the grounds, repairs, etc., up to the year 1827, was $2,433,844.13. Following the completion of the old Capitol in 1829 and the termination of the services of the architect, Charles Bulfinch, in 1830, such architectural services as were needed were performed by different architects until the year 1851, when the building of the present Senate and House wings was commenced, the plans of Thomas U. Walter having been selected in preference to others submitted. On July 4, 1851, the cornerstone of the extensions was laid in the northeast corner of the House wing. The oration was delivered by Daniel Webster, and his prophetic utterances on that occasion have been quoted many times. In the building of the Senate and House wings the exterior marble came from the quarries of Lee, Mass., and the columns from quarries of Cockeysville, Md.

This work was prosecuted under the architectural direction of Thomas U. Walter from 1851 to 1865 during his tenure as Architect of the Capitol, and thereafter certain uncompleted details were supervised by his successor, Edward Clark, whose term ran from 1865 to 1902. The present House Chamber was occupied for legislative purposes December 16, 1857, and the Senate Chamber January 4, 1859. The addition of the Senate and House wings made the construction of a new dome necessary for the preservation of architectural symmetry. The dome of the original central building was constructed of wood, covered with copper. This was replaced in 1856 by the present structure of cast iron, completed in 1865. The greatest exterior diameter of the dome is 135 feet 5 inches. The rotunda is 97 feet in diameter, and its height from the floor to where the dome closes in at the base of the lantern is 180 feet 3 inches.

The Capitol has a floor area of 14 acres, and 430 rooms are devoted to office, committee, and storage purposes. There are 17,376 square feet of skylights, 679 windows, and 550 doorways. The dome receives light through 108 windows, and from the architect's office to the dome there are 365 steps, one for each day of the year.

CAPITOL GROUNDS

The original Capitol grounds were at one time a part of Cern Abby Manor, and at an early date occupied by a subtribe of the Algonquin Indians known as the Powhatans, whose council house was then located at the foot of the hill.

These grounds, part of original reservation 2, were acquired under President Washington's proclamations of 1790 and 1797, for use as a site for the United States Capitol Building. These proclamations authorized the appropriation of all of reservation 2 which, in its entirety, included the "Capitol Square and the Mall east of Fifteenth Street West."

Additional ground (squares 687-688) was acquired under appropriations provided by Congress in 1872 and 1873 in order to obtain a better landscape surrounding in keeping with the Senate and House wings which had been added to the building since the acquisition of the original site. The purchase of this additional property completed the acquisition of the area known as the old section of the Capitol Grounds, totaling, in all, 58.8 acres.

In the immediately ensuing years, under a plan developed by Frederick Law Olmstead of New York, the terraces were built on the north, west, and south sides of the building and the entire grounds developed and improved.

During the period 1910–35 the Capitol Grounds were further enlarged and improved by the purchase, annexation, and development of 61.8 additional acres; and the addition of this new area to the 58.8 acres comprising the old grounds section gives a present total grounds area of 120.6 acres.

HOUSE OFFICE BUILDINGS

OLD BUILDING

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An increased membership of the Senate and House resulted in a demand for additional rooms for the accommodation of the Senators and Representatives, and on March 3, 1903, the Congress authorized the erection of a fireproof office building for the use of the House Members as office and committee rooms. first brick was laid July 5, 1905, in square No. 690, and formal exercises were held at the laying of the cornerstone on April 14, 1906, in which President Theodore Roosevelt participated. The building was completed and occupied January 10, 1908. A subsequent change in the basis of congressional representation made necessary the building of an additional story. The total cost of the building, including site, furnishings, equipment, and the subway connecting the House Office Building with the United States Capitol, amounted to $4,860,155. This office building contains 690 rooms, and was considered at the time of its completion fully equipped for all of the needs of a modern building for office purposes.

NEW BUILDING

Under legislation contained in authorization act of January 10, 1929, and in the urgent deficiency bill of March 4, 1929, provisions were made for an additional House Office Building, to be located on the west side of New Jersey Avenue (opposite the first House Office Building).

The cornerstone was laid June 24, 1932, and the building was completed and ready for beneficial occupancy April 20, 1933. It contains 251 two-room suites, 16 committee rooms, each suite and committee room being provided with a storeroom. Eight floors are occupied by Members; the basement and sub-basement by shops and mechanics needed for the proper maintenance of the building. The cost of this building, including site, furnishings, and equipment, was $7,805,705.

SENATE OFFICE BUILDING

The demand for a new building to be used for offices was greater for the Representatives, on account of the large number forming the membership of that body, and because the Members of the Senate were supplied with additional office space by the purchase of the Maltby Building, located on the northwest corner of B Street and New Jersey Avenue NW. However, the acquisition of this building supplied but a temporary purpose, and its condemnation as an unsafe structure created on the part of the Senators a desire for safer and more commodious quarters. Accordingly, under authorization of act of April 28, 1904, square 686, on the northeast corner of Delaware Avenue and B Street NE., was purchased as a site for the Senate Office Building, and the plans for the House Office Building were adapted for the Senate Office Building, the only change being the omission of the fourth side of the building fronting on First Street NE., this being planned for but not completed. The cornerstone of this building was laid without special exercises on July 31, 1906, and the building was occupied March 5, 1909. In June 1934 the building was completed by the erection of the First Street wing, construction of which was commenced in 1931, together with alterations to the C Street facade, and construction of terraces, balustrades, and approaches. The cost of the completed building, including site, furnishings, equipment, and the subway connecting the Senate Office Building with the United States Capitol, was $8,429,357.

CAPITOL POWER PLANT

During the development of the plans for fireproof office buildings for occupancy by the Senators and Representatives, the question of heat, light, and power was considered. The Senate and House wings of the Capitol were heated by separate heating plants. The Library of Congress also had in use a heating plant for that building, and it was finally determined that the solution of the heating and lighting, with power for elevators, could be adequately met by the construction of a central power plant to furnish all heat and power, as well as light, for the Capitol group of buildings.

Having determined the need of a central power plant, a site was selected in Garfield Park, bounded by New Jersey Avenue, South Capitol Street, Virginia Avenue, and B Street SE. This park being a Government reservation, an appropriation of money was not required to secure title. The determining factors leading to the selection of this site were its nearness to the tracks of the Pennsylvania Railroad and its convenient distance to the river and the buildings to be cared for by the plant.

The dimensions of the Capitol power plant, which was constructed under authorization of act of April 28, 1904, and completed and placed in operation in 1910, are 244 feet 8 inches by 117 feet, with a height over the boiler room of 81 feet to accommodate the coal bunkers. A later additional building, for accommodation of shops and storerooms, is located near the power plant and is built of selected red brick, it being 90 feet long, 50 feet wide, and 2 stories high. The building is located upon concrete foundations resting upon 790 simplex reinforced concrete piles; the superstructure is of red brick. There are 2 Alphons Custodis radial brick chimneys 212 feet in height and 11 feet in diameter at the top.

The buildings served by the power plant are connected by a reinforced-concrete steam tunnel 7 feet high by 4% feet wide, with walls approximately 12 inches thick. This tunnel originally ran from the power plant to the Senate Office Building, with connecting tunnels for the House Office Building, the Capitol, and the Library of Congress, and has since been extended to the Government Printing Office and the Washington City Post Office, with steam lines extended to serve the new House Office Building, the Supreme Court Building, the Annex to the Library of Congress, and the relocated Botanic Garden.

In 1935 Congress authorized the air conditioning of the Capitol, Senate, and House Office Buildings and provided therefore an appropriation of $2,550,000 and, in 1937, an additional amount of $1,672,000, including authorization for construction of a central refrigeration plant to serve the systems. An addition to the power plant building, 123 feet 2 inches long, 79 feet 6 inches wide, with a height of 37 feet 10 inches, was constructed to house the refrigeration plant. This plant was placed in operation May 16, 1938, and was, at that time, the largest central station water-cooling plant ever constructed. Its huge pumps carry chilled water through large supply mains to the four buildings served. refrigerating capacity of the plant may best be described in terms of the melting of a block of ice 50 feet by 50 feet and the height of a seven-story building every 24 hours.

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