This section is from the book "The National Capitol. Its Architecture Art And History", by George C. Hazelton, Jr. Also available from Amazon: The National Capitol Its Architecture Art and History.
" The centre of the north wing demanded light from above ; and its symmetry with the south wing, which could only be lighted by a cupola, demanded a similar construction on the north wing.
" Therefore it was almost unavoidable, and certainly it was highly advisable, that the chimneys should be carried up as well as concealed in the piers of the cupola. This had been done before, and, although the cupola was never raised above the dome, its base had existed, and, with the arches that supported it, remained unimpaired by the fire of 1814.
" . . . But, deprived of this support, the object I had to attain was this : To construct over the cavity of the Senate chamber and its wooden dome an arch or other support sufficient to bear the cupola necessary to light the centre of the house, and also to carry sixteen or eighteen chimneys concealed in the cupola, and, at the same time, to produce a handsome effect in looking up from the vestibule of the Senate, from which the whole construction would be seen. And I believe that I perfectly attained this object in all its parts, provided the arch had been made to stand".
We undoubtedly owe to Latrobe the restoration and interior finish of the old wings, as well as their surmounting cupolas and dome-shaped roofs. Statuary Hall, also, was his design. The old Capitol could not be called completed, however, until 1830, thirteen years after Latrobe's resignation and the succession to his position of Charles Bulfinch of Boston, the first architect of the Capitol who was American-born. During a visit to Washington before he had the intention of making it his home, in a letter of February 7, 1817, to Mrs. H. Bulfinch, Latrobe's successor writes: "Nothing announces a metropolis until we approach an assemblage of brick houses, forming a village, and immediately contiguous to them two stone edifices of richly ornamented architecture. These are the wings of the Congress hall; they were burnt, as far as they were combustible, and are now undergoing repair. They have been chiselled in such a manner that all external marks of fire are removed".
How Bulfinch came to be architect of the Capitol is told by himself in his brief Autobiography: "About November following , I received a letter from William Lee Esq., one of the Auditors at Washington, and in the confidence of the President, stating the probability of the removal of Mr. Latrobe, the architect of the Capitol, and proposing that I should apply for his place. I declined making any application that might lead to Mr. Latrobe's removal ; but before the end of the year, disagreements between him and the Commissioner became so serious that he determined to resign, and his resignation was immediately accepted. On receiving information of this, in another letter from Mr. Lee, I made regular application through J. Q. A., Secretary of State, and by return Post received notice from him of my appointment, with a salary of $2,500, and expenses paid of removal of family and furniture".
The new architect entered immediately upon his duties, taking the work up where Latrobe had left it; and on the 1st of May, 1818, made a report to Congress, to which the last report of Latrobe was a reply, on the state of the unfortunate arch constructed by his predecessor in the roof of the north wing, from which the following interesting extracts are taken :
" When I entered upon the duties of my office as architect of the Capitol, and examined the state of the building, I found that a large arch had been built above the third story of the north wing, which was intended to support the stone cupola or lantern on the centre of the dome. I was pleased with the ingenuity and boldness of the design by which it was intended that a great number of chimneys should be carried upon this arch, and rise in the piers of the cupola between its windows. ... I was told that this arch had been constructed under the particular direction of Mr. Latrobe, and that the stones of the band or curb that formed the opening on the crown of the arch were cut by his particular orders, and put in their places before he left the superintendence of the building. I felt perfect confidence in Mr. Latrobe's genius as an architect, and his acknowledged skill as an engineer, that he had well considered the hazard of the proposed construction, and had taken every precaution against danger ; and I gave direction to the workmen to proceed strictly according to their orders from him.
" By the 23d of April the chimney flues were all brought into their position on the crown of the arch, when the master workman thought it would be proper to loosen the centres, that the arch might be proved and take its bearings before the stone cupola should be built. On loosening the centre, it was found that the crown of the arch settled with it, and that the stones around the circular opening had moved in a few minutes so far as that the opening was four inches larger in one direction than in the other ; the joints appearing violently compressed in some parts, and open on the others. The workmen left it in alarm and considered it very hazardous. I soon came to the determination that the arch could not bear the weight of the flues and stone cupola, estimated at 200 tons more than it was already charged with ; and, after inspecting the foundation resolved to build a cone of brick from the bottom of the dome to the circular opening above, for the purpose of strengthening the arch and supporting the cupola.
" The great arch in the roof of the north wing is 40 feet in-span from north to south, and 30 ft. wide from east to west, and rises in a semi-circle ; it is intended to support a stone cupola 22 ft. in diameter, with 6 windows in its circumference, and as many piers between them, in which 18 chimney flues are to be carried up from the different apartments of the building. A circular opening is made in the crown of the arch 15 ft. wide (the inner diameter of the cupola), to convey light to the interior, and particularly to the vestibule of the Senate chamber. . . .
" One cause of the failure of this arch arises from the circumstance that the circular opening is not in the centre. . . . On taking down the centring which opened the soffit or under side of the arch to view, another cause of weakness appeared ; the arch, which is two bricks thick, is ornamented with large caissons or coffers of three feet square, sunk in the depth of one brick, or half its thickness ; these destroy the bond and connection of the work. ... It would be dangerous to trust the arch to bear the weight".
Later in the same month, Bulfinch reports :
" A cone of brick has been made under the opening of the arch ; the chimney flues are now brought into their right position, and carried up to the top of the dome roof. The work appears fair and substantial, and capable of sustaining the stone lantern which will .now immediately be built upon it".
The architect continued to devote himself assiduously to the completion of the two wings only; as they were most necessary to the use and comfort of Congress. On November 21, 1818, he reports regarding the condition of the north wing:
" The stone masons have built, on the outside, the entire balustrade of the east and west sides, and the attic of the north front, and the stone cupola over the dome. Inside, they have laid the marble stairs leading to the principal floor, completed the colonnade of the vestibule and part of the gallery of the Senate chamber. The roof has been covered with copper ; the apartments and passages of the upper story are plastered and paved ; and the doors, shutters, and other carpenter's work will be finished in a few days. The court room is proceeding in a state of preparation for the use of the court in December. The ceiling of the Senate chamber is rough plastered. . . . The rich and costly colonnade and gallery of the Senate chamber . . . is to be wholly of marble, and was contracted for in New York to be executed there, and to be delivered here in November, 1817".
In speaking of the progress on the south wing, in the same report, Bulfinch says :
" The columns of Potomac marble of the Representatives room have been prepared and set in their places ; the stone entablature, with which they are crowned, and the brick arches connecting them with the walls, are built ; the stone enclosure forming the breast of the gallery is nearly complete ; the ribs of the dome ceiling are raised and secured ; the outer roof is now raising and will be covered in a fortnight, and the ballastrade is nearly entire".
From these and other reports and letters of this period are seen the difficulty experienced and the interest taken in securing suitable marble for the beautiful pillars which adorn the old Senate Chamber, and more especially the old Hall of Representatives. The desire was so great on the part of the Commissioner and architect that, after securing sufficient breccia or Potomac marble for the shafts from the quarries in Loudon County, Virginia, Giovanni Andrei was sent in 1815 to Carrara, Italy, to procure of statuary marble their twenty-four Corinthian capitals. Latrobe, then architect of the Capitol, furnished the necessary drawings to govern in the execution of these, and passage was provided for the artist, as well as for Mrs. Andrei, his wife, on the United States corvette, John Adams.