New Facts Concerning the Pantheon

THE Pantheon of M. Vipsanius Agrippa well deserves the name given to it by topographers, the Sphinx of the Campus Martius, because, in spite of its preservation, it remains inexplicable from many points of view. This state of uncertainty relates to the general outline as well as to the details of the building. The rotunda is obviously disjointed from the portico, and their architectural lines are not in harmony with each other. On the other hand, it is evident that the Pantheon seen by Pliny the elder, in Vespasian’s time, was not the one which has come down to us, because there is no place in the present building for the Caryatides of Diogenes the Athenian, and for the capitals of Syracusan bronze which he saw and described as crowning the columns of the temple. Therefore, when I was asked, in 1881, to write an official account of the excavations undertaken by Guido Baccelli, the Minister of Public Instruction, who freed the Pantheon from its ignoble surroundings,1 I began the report by stating that the veil of mystery in which the monument was shrouded had by no means been lifted by these last researches, and that perhaps it never would be. Who would have suspected, however, that before a few years had elapsed we should discover another, nay, two more Pantheons under the existing one, and should be able to declare that Agrippa’s name engraved on the epistyle of the pronaos is historically and artistically misleading ?

To make clear the case, I must give a brief account of the fortune of the building, from Agrippa’s time to the last restoration by Septimius Severus and Caracalla.

There are two witnesses to the origin of its construction : the legend on the face of the building, M . AGRIPPA . L . F . cos . TEKTIVM . FECIT, and the record of Dion Cassius, liii. 27, “ [Agrippa] finished the construction of the so - called Pantheon.” The date of the inscription is 27 n. c., while Dion relates the events of the year 25. This discrepancy of dates may he reconciled if we suppose the inscription to commemorate the material completion of the structure, and the historian to be recording the solemn dedication of the Pantheon and of the Laconikon, which stood close by.

The same historian relates that the Pantheon was dedicated to the ancestral gods of the Julian family, namely, Mars and Venus, and that “ Agrippa wished to raise a statue to Augustus, also, so that the temple might be placed under his protection. Augustus, however, declined the proposal. In consequence of his refusal, only the statue of Julius Cæsar was placed inside ; those of Augustus and Agrippa outside in the pronaos.”

From this passage we gather the evidence that Agrippa’s temple was furnished with a portico, or pronaos. Now, as I remarked at the beginning, between the present rotunda and the portico inscribed with the name of the founder there is no artistic or structural connection. The cornices of the round body are cut up by the portico, while those of the portico are intercepted by the round body. There is a break between the two, five and a half centimetres wide, through which the light shines. This state of things has been discussed by Milizia, Fontana, Piranesi, Lazzeri, Hirt, Fea, Piale, Nibby, and Canina. The majority believe, and I believed with them in 1881, that the portico was a later addition ; in other words, that, before the refusal of Augustus to permit his statue to stand within the temple, Agrippa’s architect had not thought of the portico, and that it was added by him when the Emperor selected for his own statue a site in front of the rotunda.

No less debatable is the relation between the Pantheon and the Thermæ of Agrippa. Regarding this architects and archæologists are divided into two camps. Some believe that the rotunda belongs to the original plan of the Baths, and that it was designed for a calidarium; others deny any connection between the two. It is interesting, in view of the light now thrown, to recall what Emil Braun wrote on this subject thirty-nine years ago: “ The incomparable circular edifice originally intended by Agrippa to form the termination of his Thermæ, with which it is intimately connected, is one of the noblest and most perfect productions of that style of architecture specifically denominated Roman. When the first wonderful creation of this species came into existence, the designer of this glorious dome appears to have himself shrunk back from it, and to have felt that it was not adapted to be the every-day residence of men, but to be a habitation for the gods. It is as difficult to reconcile the statements of different authors respecting the original idea of Agrippa as it is hazardous to attempt to prove the successive metamorphoses which the plan sketched by the artist has undergone. Thus much is, however, certain : that with respect to the modal transformation of the whole the consequences have been most melancholy and injurious. The combination of the circular edifice with the rectilinear masses of the vestibule . . . has been unsuccessful, and the original design of the Roman architect has lost much of its significance. ... No one previously unacquainted with the edifice could form an idea, from the aspect of the portico, of that wonderful structure behind, which must ever be considered as one of the noblest triumphs of the human mind over matter in connection with the law of gravity.”

Eheu, quantum mutatus ab illo ! How differently we are obliged to speak and write since the last discoveries ! At the same time, the reader will notice that Emil Braun himself, in 1854, considered it difficult, if not impossible, to wrest from the Sphinx of the Campus Martius the secret of its existence and metamorphoses. We know a great deal more in 1893, but the difficulties have remained the same.

The Thermæ were built six years after the dedication of the Pantheon and of the Laconikon ; namely, in B. C. 19. It appears, also, that in this second period of the great undertaking Agrippa must have changed his mind more than once. At all events, after the year 19 we hear no more of the Laconikon, but only of the Thermæ. Was the Pantheon connected directly or indirectly with the Baths, or did it stand by itself, alone, independent, at the northern end of the quadrangle ? In other words, is it possible that the Pantheon, originally dedicated to the gods, should have been used, six years later, as a calidarium, and thus have been absorbed as an integral part into the great whole ? The question must remain unanswered ; so many alterations have taken place at the point of contact between the rotunda and the Baths that nothing is left of the first design. No other Roman structure, except the temple of Jupiter Optimus Maximus, has been so unfortunate, and has undergone so many trials. We begin to suspect that Agrippa was a jettatore.

In the year 80 of our era, during the fire of Titus, the Baths and the Pantheon were burnt down. Domitian restored both.

In the year 110, under the rule of Trajan, Pantheon fulminibus subversion est: a thunderbolt set the building on fire, and destroyed it to the level of the ground. How such a thing could have happened is a mystery, to be added to the many others connected with this wonderful structure.

In the years 120-124 Hadrian reconstructed the rotunda and the Baths, as testified by Spartianus, ch. xix.: “ Romœ instauravit Pantheum . . . (et) lavacrum Agrippœ.”

Some other dreadful accident must have happened soon after, for Hadrian’s successor, Antoninus Pius, is said to have restored templum Agrippœ (Capitolin., ch. viii.).

In the year 202, Septimius Severus and Caraealla PANTHEVM VETVSTATE CORRVPTVM RESTITVERVHT. These words, engraved on the same entablature which is inscribed with the name of the founder, are more than enigmatic. How is it possible that a structure of immense solidity, only eighty years old if we reckon from the restoration of Hadrian, fifty or sixty if we reckon from the restoration of Antoninus, should have become in so short a time “ vetvstate corrvpta ” ? It may help us to explain the case if we assume that while the upper part of the Pantheon was struck by lightning and attacked by flames, the lower part was submerged by the Tiber three or four times a year. Fire and water must have increased tenfold the normal wearing action of time.

Summing up the information supplied to us by writers and inscriptions, we had come to these inferences, which were hypotheses rather than conclusions : first, that the present Pantheon, inscribed with the name of Agrippa, was substantially his work ; second, that the portico was a later addition, or alteration, to the original plan ; third, that some details of the structure, especially the inner decoration, were the work of Hadrian and of Severus and Caraealla; fourth, that the Pantheon had never been used as a calidarium. Such were the current theories at the beginning of 1892.

At that time, the Department of Antiquities was raising a movable scaffolding to repair the dome in two or three places, where rain water had filtered in and damaged the coating of stucco. A distinguished pupil of the French Academy (Villa Medici), Monsieur Louis Chedanne, actively engaged in the architectural study of the Pantheon, was allowed by the department to take advantage of the scaffolding, and to examine the structure of the great dome. He was surprised to find it built of bricks stamped with a date (Agrippa’s bricks are not dated) ; and the date was of the time of Hadrian. It was felt to be desirable to ascertain at once whether these bricks belonged to a local and unimportant restoration at the beginning of the second century, or whether they bore testimony to the chronology of the whole edifice.

The masonry of the rotunda, like that of Hadrian’s mausoleum, is faced with small triangular bricks, and with rows of tegulœ bipedales (large bricks, one foot ten inches square, two and a quarter inches thick) at intervals of five feet, one above the other. Since these tegulæ bipedales are dated, as a rule, holes were bored into them in about fifty places, and as many brick stamps were found ; some on the outside facing, others in the thickness of the wall, in the foundations, in the dome, in the staircases, in the arches and vaults; in short, wherever the search was made.

The dates vary from the year 115 to 125 of our era. I mean, they are the dates of tilers who produced bricks between those dates. A stricter chronological investigation, too minute and too technical to be recorded in these pages, has enabled us to ascertain that the reconstruction of the Pantheon began in the year 120, and was finished in 124. It was absolute, complete, from the lowest depths of the foundations to the skylight of the dome ; it included the rotunda as well as the portico, whose foundations have also been explored to a depth never reached before. In short, the present Pantheon, the world-known masterpiece, — counted by Ammianus Marcellinus among the wonders of Rome, considered by Michael Angelo “ disegno angelico e non umano,” proclaimed by Urban VIII. “ œdificium toto terrarum orbe celeberrimum,” 2 — is not the work of Agrippa, whose name it bears, but the work of Hadrian. The fact, however startling, is confirmed by other evidence, to which very little or no attention has been paid. In a pamphlet entitled Conclusione per la integrità del Pantheon, Rome, 1807, Carlo Fea, then Commissioner of Antiquities, describes how, on September 13, 1804, he found three brick-stamps of the time of Hadrian, — one in the thickness of the round wall, one under the flagstones of the portico, one in the so-called Laconieum. Piranesi, likewise, who witnessed the barbaric “ restorations ” of Benedict XIV. in 1747, read on the brick of the attic other names and dates of the same period.

We must now meet the question which at once confronts us in this new state of things. In rebuilding the Pantheon in its entirety, from top to bottom, from the steps of the portico to the small apse at the opposite ei I of the structure, did Hadrian respect the architectural form of Agrippa’s (and Domitian’s) building, or did he erect a new structure of his own design, altogether different in general outline and details ? This is the problem, the solution of which we are anxiously awaiting from the investigations which the Department of Antiquities is making at all available points; wherever, that is, they can be carried on without injury to the monument. The following considerations may help the student to unravel the tangle.

If we read on the face of the Pantheon the names of Agrippa, the founder, and of Septimius Severus, the restorer in B. c. 202, and not that of Hadrian, the explanation is ready at hand. " Hadrian never inscribed his name on the monuments which he designed and raised, with the exception only of the temple which he dedicated to Trajan,” at the northern end of the Forum. So says Spartianus in the nineteenth chapter of that Emperor’s life. The omission of the name is thus easily explained. Some one, however, has succeeded in finding it inside the rotunda. In a paper read before the Archæological Academy by Stefano Piale, June 26, 1828,3 I find the following passage:—

“ I have been kindly informed by our worthy secretary, Filippo Aurelio Visconti, that when the tribune (the main altar and apse) of the rotunda was restored, a short time ago, the name of Julia Sabina, the Empress of Hadrian, was found engraved on the columns of pavonazzetto. This confirms the theory which I have long held, that the apse does not belong to the original structure, but is the work of Hadrian. He made use of it as a bench, when he, together with other magistrates, sat in the Pantheon to administer justice and dictate the law, as we are told by Dion Cassius.” He was fond of presiding on the bench, and held sittings in his own palace, in the Forum, in the Pantheon, and elsewhere.

The inference to be drawn from these remarkable statements is that the inscription on the face of the building, which we had always supposed to be the “ signature,” as it were, of the first builder of the Pantheon, must be considered simply as homage paid to his memory by some one who did the work over a century and a half later. This some one was a great artist, in the true sense of the word, a worthy rival of the great Apollodoros, the builder of the Forum of Trajan. The temples of Venus and Rome, of Matidia, of Trajan, of Neptune, designed and built by Hadrian, his Own mausoleum, the bridge which leads to it, count among the architectural masterpieces of ancient Rome. To a man possessed of such genius the rebuilding of the Pantheon must have proved an almost irresistible temptation to show his power; it is more than probable, therefore, that the original design would have been changed, enlarged, improved. This supposition, namely, that the pre-Hadrianite structure was different in shape, size, material, etc., seems to be supported by the record of the two fires in the times of Titus and Trajan. The present building is absolutely fireproof :4 therefore the Pantheon of Agrippa and of Domitian, wrecked by fire in the years 80 and 110, must have been different from that of Hadrian and Septimius Severus, which does not contain one inch of inflammable matter.

To pass from theory to fact, from speculation to substantial evidence, there was but one way left open: to make a search under the rotunda and its portico. The delicate and hazardous work has been admirably carried out by all persons concerned with it, but the results are rather disappointing; they have thrown even move confusion, uncertainty, and darkness on the controversy. Never have I found myself, after many years of experience, confronted with such a problem as this; every time I think I have grasped and conquered it, by some new phase I am thrown out of balance again. The wisest course is to lay the bare facts before the reader, and let him judge for himself.

First as to the interior of the rotunda. The excavations made in a line from the centre to the chapel of the Madonna del Sasso, and also from the centre to the entrance gate, have shown the existence of an earlier marble pavement at the average depth of six feet under the present one (Hadrian’s). The pavement is composed of a bed of concrete, over which are laid slabs of giallo antico and pavonazzetto, marbles which were used in this form and for such purpose only under the empire. The pavement is not horizontal, but slopes from the centre towards the circumference, like the lower floor of the arena of the Coliseum. The pavement, therefore, belongs to a round structure covered, by a dome with a skylight, through which the rain could fall. The same pavement has been found running under the portico, at a depth of five feet. The bed of concrete is one foot thick ; the marble slabs from two to three inches. The pavement slopes inward, namely, from the front of the portico towards the bronze door, with an inclination of one foot in thirty.

As regards the portico itself, — under and near which the excavations have been carried on with much more freedom than those in the inside, — it has been found to rest on a magnificent substructure of travertine, much larger, and of different design. The level of the platform is nearly eight feet lower than the floor of Hadrian’s portico, and between the two there are traces of an intermediate one.

It is very difficult for me to make this account clear without the help of plans and diagrams. However, summing up the facts which I have tried to describe, and the results of the search made by the Department of Antiquities, we reach the following conclusions : —

(1.) The present Pantheon, portico included, is not the work of Agrippa, but of Hadrian, and dates from 120-124 A. D.

(2.) The columns, capitals, and entablature of the portico inscribed with Agrippa’s name may be original, and may date from 27-25 B. C. ; but they were first removed, and then put together again by Hadrian. The original portico was decastyle, as shown from the foundations of travertine which project right and left of the present octostyle portico, enough to admit one more intercolumniation at each end.

(3.) The original structure of Agrippa may have been rectangular instead of round; but we can produce no decisive proof that it was.

(4.) The platform, built of huge blocks of travertine, some eight feet below Hadrian’s level, dates from the time of Agrippa.

(5.) The intermediate marble floor (from three to two feet higher than Agrippa’s, from five to six feet lower than Hadrian’s) dates, most likely, from the time of Domitian. The fact that this pavement slopes from the centre towards the circumference shows that Domitian’s Pantheon was round, like the present one.

(6.) Septimius Severus and Caracalla did not alter the shape of the structure. Their restorations were only superficial, and relate mostly to the attic inside, which they encrusted with slabs of porphyry and serpentine. Their beautiful decorations were destroyed by Pope Benedict XIV. in 1747.

(7.) The excavations undertaken by the Italian government have not yet come to an end ; there is still a very faint hope of discovering new dates which may confirm or destroy the suppositions expressed above.

(8.) If the outside architecture of Hadrian’s rotunda is rather coarse, and not worthy the exquisite beauty of the interior, we must remember that the round body — the front excepted — was entirely concealed and made invisible by the Thermæ.

The fortune of the building, from its last restoration in 202 A. D. to our own times, is too well known to be narrated again in these pages. I shall mention two episodes only : one relating to the destruction of the roof of the portico by Pope Barberini, the other to the discovery of Raphael’s body in 1833.

Giacinto Gigli, a diarist contemporary with Urban VIII., thus describes his shameful action : " In 1625, while the war cry was raised from one end of the peninsula to the other, Urban VIII. made a great provision of arms and ammunition, and more especially of artillery. To provide himself with a copious stock of materia prima, he caused the portico of the Pantheon to be stripped of its bronze roof, a marvelous work, resting on the capitals of the columns. But no sooner was the destruction accomplished than he found the alloy of the metal not hard enough for artillery work.5 Meanwhile, the population, who flocked in great numbers to see what was being done at the Pantheon, were deeply grieved, and complained that such a beautiful work of antiquity, the only one which had escaped plunder from the barbarians, should now be dismantled. But the intention of the Pope was not to destroy the Pantheon ; he gave orders for the construction of a new roof, and showed his willingness to make other improvements. The weight of the metal stored in the apostolic foundry was 450,251 pounds, of which 440,877 represented the weight of the beams, 9374 that of the nails alone. Besides the four columns of the baldacchino in S. Peter’s, eighty guns were cast from it, and mounted on the bastions of Castel S. Angelo.”

The story about the casting of the four columns of the baldacchino is not correct; the bronze, save a few thousand pounds, was all absorbed by the guns of Castello. Giano Nicio Eritreo, another eye witness, thus speaks of the event: “ Our good pontiff, Urban VIII., could not bear the idea that such a mass of metal, intended for loftier purposes, should humble itself to the office of keeping off forever the rain from the portico of the Pantheon. He raised it to worthier destinies, because it is more becoming that such noble material should keep off the enemies of the Church rather than the rain. At all events, Agrippa’s temple has gained more than it has lost, because Pope Urban VIII. has provided it with a much better roof ” (tectum multo quam antea elegantius). I doubt whether Giano Nicio Eritreo was in his right senses when he wrote these lines.

Carlo Fea has discovered among the accounts of the Pope’s treasury that concerning the fate of the bronze. The casting of the eighty guns (bombarde) used up 410,778 pounds, worth 67,260 sendi. The small fraction that was left was handed over to the Apostolic Chamber and used for other purposes. The metal for the baldacchino was supplied from Venice.

I have discovered in the Uffizi in Florence, and in other, private, collections, a set of drawings by Sallustio Peruzzi, Sebastiano Serlio, Giovanni Antonio Dotio, Jacopo Sansovino, and Cherubino Alberti, which show the construction of the bronze trusses in their minutest details. The main beams were composed of three sheets, two vertical, one horizontal, riveted together in this shape.

The beams as well as the heads of the nails were ornamented with gilt rosettes. One of the nails was presented as a souvenir to the Duke of Alcalá, and was placed in the private museum of that distinguished statesman.

The second and latest episode in the history of the Pantheon is the discovery of the remains of Raphael, which took place on September 14, 1833. Doubts had been raised as to the genuineness of the skull preserved in the Accademia di S. Luca ; while Carlo Fea had advanced the theory that Raphael’s remains were not to be found under the great dome of the Pantheon, but in the chapel of the Urbinati, in the church of S. Maria sopra Minerva. The Congregazione dei Virtuosi (an association of architects, painters, and sculptors, instituted in 1543 by Desiderio Adintorio,6 whose assembly rooms are in the attic of the Pantheon itself) decided to settle the controversy by exploring the chapel of the Madonna del Sasso, the traditional burial-place of the great man. I own an autograph account of the event, signed by Gaspare Servi, the leader of the explorations, as well as a sketch in watercolors, taken by Carlo Ruspi on the very day of the find. The search began in the early morning of September 9, in the presence of a committee of eminent artists, prelates, and public notaries. It took five days to remove the massive masonry of the altar and to reach the arcosolium under the statue of the Madonna del Sasso, the place distinctly mentioned by Vasari in Raphael’s biography as well as in Lorenzetto Lotti’s. “ Raphael provided in his will for the restoration of one of the antique tabernacles in the church of S. Maria Rotonda, and expressed the wish to be buried in it, under the new altar, and under a marble statue of Our Lady.” In the life of Lorenzetto he adds : “ In execution of Raphael’s will, he modeled a marble statue four cubits (quattro braccia) high, to be placed over his tomb in S. Maria Rotonda, in the tabernacle restored at his expense.”

The arcosolium appears to have been built in a hurry, together with the wall which sealed its opening,— a particular which agrees well with the account of the burial. Raphael died in the night between Good Friday and Easter Eve (1520). His remains were laid to rest on the following night, and the wall which seals the opening of the crypt must have been finished before dawn ; that is to say, before the Easter office began. Every kind of material was used in it, bricks, tufa, travertine, and chips of porphyry and serpentine.

At noon of the 14th of September, 1833, the last stone was removed, and the excited assembly beheld for the first time the remains of the " divine painter.” They were lying in a coffin made of deal boards nailed with small iron nails. It seems that the waters of the Tiber, by which the Pantheon is periodically inundated, had filtered into the tomb, in spite of its being surrounded by a wall two feet thick, and had caused the wooden coffin to decay, and the bones to be covered by a layer of mud. The first bones to appear were the right scapula and the crest of the right ileus. At 2.25 P. M., Gaspare Servi announced the discovery of the skull, the leading feature of which was a double set of strong, healthy, shining teeth. At 2.30, Baron Camuccini, the painter, made a pencil sketch of the skeleton, which shows that the body had been laid to rest well composed, with hands crossed on the breast, and the face looking up towards the Madonna del Sasso, as if imploring from her the peace of the just. The size of the skeleton, from the vertex of the skull to the protuberance of the heel, was measured by means of a wooden compass of the kind used by marble-cutters : it was given at sixteen hundred and sixty-four millimetres, exactly eight times the measure of the head. The sceletognosis, or expert examination of the bones, was made by the “ last of the Frangipanis,” the learned surgeon Baron Antonio Trasmondo, Among the peculiarities described in his report, there is a " great roughness of the thumb ” which is characteristic of painters.

The paper of attestation was signed by seventy - one eminent men, among whose names I notice that of Carlo Fea, who had always denied the existence of Raphael’s tomb in the Pantheon. When he was shown the tomb and the skeleton, the gruff but honest veteran of Roman excavations was heard to say, “ Ergo erravimus ! ”

The mud which filled the arcosolium was sifted most carefully, with no result worthy of notice. The missing tooth of the lower jaw (the last molar on the left) was not found. There were, however, some tags and small rings for lacings, which proves that Raphael was buried in his official robe of cubicularius pontificis, a copy of which is given by some contemporary painters.

After being exposed in a glass case for some days, Raphael’s remains were again buried under the Madonna del Sasso, near those of Maria da Bibiena, his betrothed, the niece of the wellknown Cardinal Bernardo Divizio, as the inscription over the girl’s grave says : LÆTOS HYMNEOS MORTE PRÆVERTIT. ET ANTE NUPTIALES FACES VIRGO EST ELATA.

Rodolfo Lanciani.

  1. Il Pantheon e le Terme di Agrippa. Prima Relazione a sua Eccellenza il Ministro della Istruzione pubblica. Roma: Salviucei. Ottobre, 1881. Id. id. Seconda Relazione, Agosto, 1882.
  2. The inscription on the pronaos.
  3. Un monumento ... della basilica di S. Paolo, Roma.
  4. The wooden framework of the roof of the portico is an innovation of the seventeenth century ; the original trusses were cast in bronze.
  5. Gigli affirms that the metal “ was copiously mixed with silver and gold.”
  6. The first members of this artistico-religious company were Ligorio, Labacco, Sieciolante, Vignola, Pierino del Vaga, Giovanni da Udine, etc.