Lecture 12: The Pantheon and it’s Progeny

Built: AD under Emperor Hadrian Foundation: 24' thick at base and steps to 21' at ground level Rotunda: concrete, 20' thick; 142' diameter Oculus: concrete: 7.5' thick; 27' diameter Interior Columns: 3' diameter, 29' tall topped with a Corinthian capital of 4' totaling 32' 9" tall, 25 tons each Portico: 16 granite columns 39' tall, 5' diameter, 60 tons each Pantheon Rome, Italy

Most historians, however, claim that Emperor Marcus Agrippa built the first Pantheon in 27 BC, a rectilinear, T-shaped structure, 144 feet by 66 feet (44m x 20m), with masonry walls and a pitched timber roof. It burned in the great fire of 80 AD, was rebuilt by Emperor Domitian, but was struck by lightening and burned again in 110 AD.

In the aftermath of the Battle of Actium (31 BC), Agrippa built and dedicated the original Pantheon during his third consulship (27 BC). Agrippa's Pantheon was destroyed along with other buildings in a huge fire in 80 AD. The current building dates from about 125 AD, during the reign of the Emperor Hadrin, as date- stamps on the bricks reveal. It was totally reconstructed with the text of the original inscription ("M·AGRIPPA·L·F·COS·TERTIVM·FECIT" meaning, "Marcus Agrippa, son of Lucius, consul for the third time, made it") which was added to the new facade, a common practice in Hadrian's rebuilding projects all over Rome. Hadrian was a cosmopolitan emperor who traveled widely in the East and was a great admirer of Greek culture. He might have intended the Pantheon, a temple to all the gods, to be a kind of ecumenical or syncretism gesture to the subjects of the Roman Empire who did not worship the old gods of Rome, or who (as was increasingly the case) worshipped them under other names. How the building was actually used is not known.

Agrippa temple

By 120 AD, Hadrian began designing a Pantheon reminiscent of Greek temples and far more elaborate than anything Rome had yet seen. His plans called for a structure with three main parts: a pronaos or entrance portico, a circular domed rotunda or vault, and a connection between the two. The rotunda's internal geometry would create a perfect sphere, since the height of the rotunda to the top of its dome would match its diameter: 142 feet (43.30 m). At its top, the dome would have an oculus or eye, a circular opening, with a diameter of 27 feet (8.2m), as its only light source. Click to Enlarge Click to Enlarge

The 4,535 metric ton weight of the concrete dome is concentrated on a ring of voussoirs 9.1 meters (30 ft) in diameter which form the oculus while the downward thrust of the dome is carried by eight barrel vaults in the 6.4 meter (21 ft) thick drum wall into eight piers. The thickness of the dome varies from 6.4 meters (21 ft) at the base of the dome to 1.2 meters (4 ft) around the oculus. The height to the oculus and the diameter of the interior circle are the same, 43.3 meters (142 ft.), so the whole interior would fit exactly within a cube (alternatively, the interior could house a sphere 43.3 meters (142 ft.) in diameter). The Pantheon holds the record for the largest unreinforced concrete dome. The interior of the roof was possibly intended to symbolize the arched vault of the heavens. The Great Eye at the dome's apex is the source of all light. The oculus also serves as a cooling and ventilation method. During storms, a drainage system below the floor handles the rain that falls through the oculus. The top of the rotunda wall features a series of brick-relieving arches, visible on the outside and built into the mass of the brickwork. The Pantheon is full of such devices - for example, there are relieving arches over the recesses inside - but all these arches were, of course, originally hidden by marble facing on the interior and possibly by stone revetment or stucco on the exterior.

Centering -The Romans created the Pantheon's form with earthworks and timber - an arduous, time-consuming process. The Pantheon's concrete was a mixture of pozzolan, lime and a small amount of water. That mixture was tamped - not poured - into place. Today, we have portland cement, which is easily ten times stronger and much easier to work with. All concrete is weak in tension. We strengthen our concrete with reinforcing steel (rebar). The Romans did not have that option. They used ropes of vitreous china for reinforcement. To further compensate for the weakness and weight of the concrete, the Romans built extremely thick footing and drum walls. Otherwise, the weight of the dome would have spread the vertical walls of the drum and the Pantheon would not have lasted

coffers The interior features sunken panels (coffers) which, in antiquity, may have contained bronze stars, rosettes, or other ornaments. This coffering was not only decorative, but also reduced the weight of the roof, as did the elimination of the apex by means of the oculus

Doors of the Pantheon

Aedicula with triangular and segmental pediments

Dome sizes

Hadrian said, "My intentions had been that this sanctuary of All Gods should reproduce the likeness of the terrestrial globe and of the stellar sphere...The cupola...revealed the sky through a great hole at the center, showing alternately dark and blue. This temple, both open and mysteriously enclosed, was conceived as a solar quadrant. The hours would make their round on that caissoned ceiling so carefully polished by Greek artisans; the disk of daylight would rest suspended there like a shield of gold; rain would form its clear pool on the pavement below, prayers would rise like smoke toward that void where we place the gods."

Since the Renaissance the Pantheon has been used as a tomb. Among those buried there are the painters Raphael and Annibale Carrachi the composer Archangelo Carelli, and the architect Baldassare Perucci. Architects, like Brunelleschi, who used the Pantheon as an aid when designing the dome of the Cathedral of Florence, looked to the Pantheon as inspiration for their works.

Santa Maria del Fiore in Florence, Italy 1296 Arnolfo di Cambio 1334 Giotto and Pisano 1349 Francesco Talenti Then Ghini, Arnoldi, Orcagna, and others 1419 Brunelleschi and Ghiberti The basilica was built on the site of a previous cathedral, Santa Reaprata. The new church was designed by Arnolfo di Cambio in 1296 After Arnolfo died in 1302, work on the cathedral slowed for the following thirty years. The project obtained new impetus, when the relics of San Zanobius were discovered in 1330 in Santa Reparata. In 1331, the Arte della Lana (Guild of Wool Merchants) took over exclusive patronage for the construction of the cathedral and in 1334 appointed Giotto to oversee the work. Assisted by Andrea Pisano, Giotto continued along di Cambio's design. His major accomplishment was the building of the campanile. When Giotto died in 1337 Andrea Pisano continued the building, until work was again halted due to the Black Plague in 1348.Arnolfo di CambioSan ZanobiusGiottoAndrea PisanocampanileBlack Plague In 1349 work resumed on the cathedral under a series of architects, commencing with Francesco Talenti, who finished the campanile and enlarged the overall project to include the apse and the side chapels. In 1359 Talenti was succeeded by Giovanni di Lapo Ghini (1360– 1369) who divided the center nave in four square bays. Other architects were Alberto Arnoldi,, and Orcagna. By 1375 the old church Santa Reparata was pulled down. The nave was finished by 1380, and by 1418 only the dome remained incomplete. In 1419, the Arte della Lana held a competition to design a dome and cupola for the cathedral. The two main competitors were Lorenzo Ghiberti (famous for his work on the "Gates of Paradise" doors at the Baptistery) and Filippo Brunelleschi with Brunelleschi winning and receiving the commission.Francesco TalentiapseGiovanni di Lapo GhiniAlberto ArnoldiOrcagnanave Arte della LanaLorenzo GhibertiFilippo Brunelleschi The building of a stone dome posed many technical problems. Though Brunelleschi drew his inspiration from the great dome of the Pantheon in Rome, the use of concrete had long since been forgotten.[citation needed] He would have to build the dome out of bricks. To show what his dome was to look like, he constructed a wooden and brick model with the help of Donatello and Nanni di Banco (on display in the Museum Opera del Duomo). Brunelleschi won by a nose. His model served as a guide for the craftsmen, but was intentionally incomplete, as to ensure his control over the construction. Pantheoncitation neededDonatello Wikipedia.

Le Pantheon St. Genvieve in Paris, begun in 1758 by Jacques-Germain Soufflot. Because Soufflot died the building was finished by his pupil, Jean-Baptiste Rondelet, in The new French Revolutionary government changed it into a mausoleum for important French heroes.

Villa Rotunda, , Andrea Palladio, architect, Vicenza, Italy

Library, University of Virginia, , Thomas Jefferson, architect, Charlottesville, VA

Charlottesville, Virginia University of Virginia, , Thomas Jefferson, architect

The City of Rome Forum Romanum, 1st century BC - AD 4th century Theater of Marcellus, 11 BC *Flavian Amphitheater (Colosseum), AD *Forum of Trajan, AD , Apollodorus of Damascus, architect (design includes forum, Basilica Ulpia, Column of Trajan, Greek and Latin Libraries, Markets of Trajan, and Temple of Divine Trajan) *Arch of Titus, AD 81 c.f. Arch of Septimius Severus AD 203; Arch of Constantine, c. AD Baths (Thermae) of Diocletian, AD