The principal object remaining in these baths is the great hall, now converted into the Church of Santa Maria degli Angeli. This was performed under M. A. Buonarroti, who made the principal entrance at the end. Vanvitelli, the last of the celebrated architects of Italy, re-opened the ancient entrance on the side, and by uniting the circular vestibule with the chief room, and adding a choir on the opposite side, he gave the church length in that direction. The four side niches have been filled up, and the length, or what is now the width, is increased, by opening into it two other chambers. In its present state, the great hall, with the two additional rooms, forms a transept; but as this hall constitutes, on every account, the principal feature of the place, it ought certainly to form the nave, and the alteration was injudicious. We do not expect great purity of taste in the time of Dioclesian, yet the details are by no means contemptible, and the largeness and boldness of the parts produce a great appearance of magnificence.
The first room which we now enter is a circular vestibule, where the supine arches of the four openings are particularly offensive, because they are very large in proportion to the building; some scheme arches in the great hall are also disagreeable, but the hall itself is a noble room, and produces the full effect of its large dimensions. There is a pleasure arising from these large and simple parts, which it is impossible to describe, and which I long in vain to communicate to you. The old work is generally distinguishable from the modern additions; indeed, no pains have been taken to copy exactly the antique. Of the principal columns, four have Corinthian, and four Composite capitals; and this seems to have been originally the case, though the columns themselves are now, some of granite, and some of stuccoed brickwork. The groined vaulting is whitewashed, and has no ornament, except the brass knobs to which the lamps were anciently suspended.
The ground of the church has been raised, because it was damp; we wonder why it should not rather have been drained, since the situation is elevated. The present want of height is a sensible defect; it does not, I think, exceed two-thirds of the width, and perhaps was not originally more than three-fourths. I would by no means attempt in this style of architecture to emulate the proportionate height of the Gothic, whose peculiar character requires great elevation; but the height ought not to appear less than the width, and therefore should probably a little exceed it. If it is more than this, it should be sufficiently increased to make the height the characteristic of the room, the dimension which first impresses itself on the observer. Intermediate proportions would be inferior to either; it is not in architecture alone that half measures fail.
From the church we may visit the convent, both for its ancient fragments, and its modern architecture. It contains a large square, of which the centre is adorned by some noble cypresses, and the surrounding cloisters are said to be the production of M. Angelo. The disposition of the kitchen chimney in this convent pleased me much; it is a deep recess lighted by two windows, and having the stoves placed along the middle. Besides the general flue to take off the steam, &c. there are some smaller ones for the smoke.
Proceeding from these baths to the extremity of the Via del Macao, we find in a vineyard, a mound of earth said to be part of the agger of Servius Tullius, and the range of arches stretching towards the gate of San Lorenzo, is part of the Marcian aqueduct, now carrying the Acqua Felice; but I shall reserve aqueducts and gates to a future letter, and pass on to the church of Santa Bibiena, where there are some ancient columns, and a statue of the saint by Bernini. It has been much admired, but like so many other works of this artist, fails in the want of apparent ease and simplicity of nature. By a gate which is not always open, we may pass into the inclosure containing the ruin, usually called the temple of Minerva Medica, rising in the midst of artichokes and brocoli. The principal remain is a large, domed, decagonal hall, a form not common in the Roman antiquities, with nine large niches, each occupying almost the whole of their respective sides, the tenth being the situation of the doorway; and a window over each. The dome is partly destroyed, and the remaining portion perforated in many places, shewing the ancient construction to have been formed by ribs tending to a centre, while the intervals are filled up with rubble. There are some remains of other rooms adjoining. The whole is overgrown with the lentiscus and other shrubs and plants. It forms a picturesque object, but it seems impossible to determine its primitive destination.
Near this is the Columbarium, or sepulchre of the Aruntian family. You may think there is little resemblance between a tomb and a dove-cot, but this name arises from the little recesses, compared to pigeon-holes, which contain the cinerary urns. It is, I believe, the most perfect of any remaining, and accessible about Rome, but it is seldom that any body is in the way, to exhibit it, and I have not yet been able to obtain admission. We leave this vineyard just by the Porta Maggiore, and passing under the beautifully built, brick arch of the Claudian aqueduct, continue our walk to the Temple of Venus and Cupid, which stands in the garden of a convent. A part of the great niche is nearly all of this which is left standing. Some of the brick facing remains, and a few other foundations of walls, little above ground. The shattered piers and arches of the ancient aqueducts exhibited in these gardens, are perhaps more interesting than the fragment of the temple. By this, is the church of the holy cross, which I have already described to you, as that of the Santa Croce in Gerusalemme, and the Anfiteatro Castrense, which I mean to describe with the city wall, of which it forms part. We then pass under the wall among rows of trees, on turf now covered with the Anemone hortensis, to the church of St. John Lateran, stopping by the way to look at the Triclinium and the Scala Santa. After passing these objects we arrive at the baptistery of Constantine; the obelisk, which is the largest in Rome, and the hospital; a fine establishment, but according to the Roman theory, subject to mal aria nearly as much as the larger receptacle at Santo Spirito, which is under the Vatican and close to the Tiber, while this is in an elevated and airy situation. From this we follow a narrow, winding, and unfrequented lane, which will lead us under the ancient arch of Dolabella and Silanus, consuls under Augustus, in the year of Rome 763. It was of travertine, but it has been eked out with brickwork under Nero, in order to make it carry a portion of the Aqua Claudia from the Cœlian hill to the Palatine.
The Church of San Stefano rotondo is a curious edifice, which has been supposed by some, to have been a temple of Faunus, or of Claudius; others say, with every appearance of reason, that it was no temple at all; but when they proceed to state that it was a market, I follow them with less confidence. The body, or most elevated part, consists of a circular wall supported on twenty columns and two piers. The columns are not all of a size, but on an average are about four diameters apart, and about eight and a half high. The architrave, frieze, and cornice united, only form a sort of architrave, of perhaps one diameter and a half; yet it does not look so much oppressed by the great wall above, as the engravings we have of it give us reason to expect. Faulty and defective as it is, it perhaps might serve as a lesson, that a wall rising immediately on the architrave of a circular colonnade, would not have an unpleasing effect; and that with this simple arrangement, a height equal to the width, would be quite sufficient. At present the building is singularly spoilt, by a wall running across the middle of it, apparently to support the roof; but it is in fact as useless as it is ugly. This wall is open below, with three arches resting on the side walls, and on two Corinthian columns. The capitals of the circular colonnade are Ionic, various, but all bad, and the bases of all forms. The two middle columns are very fine, with good bases, and Corinthian capitals. The cross wall is conjectured not to have been a part of the original building, but nobody knows when it was added. A double aisle surrounds this central part, divided by a range of columns, which are smaller than those of the first circle, and not disposed so as to have any correspondence with them. The outer circuit is a plain wall, but part of the second aisle is divided into chapels. It is completely a building made up with the spoils of others, and the few restorations are miserably executed; circumstances which favour the idea that it was erected in the time of Constantine. It is too bad for us to believe it of an earlier date, and after him, few if any public buildings were executed in Rome, except churches. The piety or superstition of the times seems to have continued the erection of these during the darkest and most unhappy periods of falling Italy; yet there seems to be a deficiency, even of religious structures, from the beginning of the fourth, till towards the end of the seventh century, when a new character and new relations began to develop themselves.
At a very little distance from the church of San Stefano, is the Navicella, a marble boat, placed by Leo the Tenth in front of a church which receives its name from it, but where Leo found it, I cannot tell you. The church was designed by Raphael; a range of five arches forms a sort of portico, above which rises the nave, corresponding in width to three of these arches, and finishing with a pediment. The simplicity of the design, and its apparent correspondence with the internal structure, produce a pleasing effect; but instead of one large window in the end of the nave, Raphael has introduced three small ones, of which the middle is circular, and the composition is sadly spoilt by them. Giulio Romano was employed in painting the internal friezes.
After leaving the Navicella, we may visit the Church of Santi Giovanni e Paolo, enriched like so many others, with antique columns of granite and marble, both in the portico and in the nave. I have already mentioned the antiquities in the convent. Continuing our walk along the lane on the side of the church, we pass between massive substructions, and in the garden adjoining there are considerable remains, principally I believe, of the aqueduct of Nero, which is a branch of the Claudian. Piranesi places here the Nymphæum of Nero, with which he unites the Vivarium built by Domitian; here also the house of Scaurus is supposed to have stood, and these fragments may be parts of one or the other, or perhaps of both. Issuing from this lane, we turn to the left, and ascend to the Church of San Gregorio, which is preceded by one of those courts, or atria, which you know I always admire; but in this there is nothing particularly good, beyond the general disposition. The grand object here is not the church, but an adjoining chapel dedicated to St. Andrew, which is one of three united together, but having no communication with the church. This chapel is adorned with two frescos, (not to mention minor objects) one of which represents the flagellation of the saint, by Domenichino, and the other his adoration of the cross, previous to his martyrdom, by Guido. They are very fine, but they are beginning to suffer.
Descending from the church of San Gregorio towards the south-west, we reach the southern angle of the Palatine, where the Septizonium formerly stood. It was destroyed by Sixtus the Fifth, and the columns, and probably some of the other materials, were employed in the Vatican. Antiquaries have imagined from the name, that seven successive orders must have been employed here, not reflecting that three orders would produce the appearance of seven zones or bands. First, the pedestal on which the whole is placed, which forms a solid mass; then a range of columns and voids; then another solid mass composed of the entablature of the first order, and the continued plinth and pedestals of the second. The fourth zone would be composed of the columns of the second order, and the voids between them; these open bands having always a different character and appearance from the solid ones, however composed. The fifth of the entablature and pedestals as before, or if there were no pedestals, by the entablature alone. These solid zones would have the appearance of being striped horizontally by the shadows of the mouldings, while the columns would give to the open bands the appearance of being striped vertically. Sixthly, the columns of the third order. Seventhly, the entablature, and whatever might crown the edifice, and this disposition is exactly correspondent with the idea we entertain of the building from old engravings.