Modern Rome is about thirteen miles in circuit, and is divided by the Tiber into two parts. In 1830, Rome contained 144,542 inhabitants, 35,900 houses, 346 churches, 30 monasteries, and upwards of 120 palaces. The view of the majestic ruins; the solemn grandeur of the churches and palaces; the recollections of the past; the religious customs; the magic and almost melancholy tranquillity which pervades the city; the enjoyment of the endless treasures of art—all conspire to raise the mind of the traveler to a high state of excitement. The churches, palaces, villas, squares, streets, fountains, aqueducts, antiquities, ruins—in short, everything proclaims the ancient majesty and the present greatness of Rome. Almost every church, palace, and villa is a treasury of art. Among the churches, St. Peter's is the most conspicuous, and is, perhaps, the most beautiful building in the world. Bramante began it; Sangallo and Peruzzi succeeded him; but Michael Angelo, who erected its immense dome, which is four hundred and fifty feet high to the top of the cross, designed the greatest part. Many other architects were often employed upon it; Maderno finished the front and the two towers. The erection of this edifice, from 1506 to 1614, cost 45,000,000 Roman crowns. Before we arrive at this grand temple, the eye is attracted by the beautiful square in front of it, surrounded by a magnificent colonnade by Bernini, and ornamented by an Egyptian obelisk, together with two splendid fountains. Upon entering the vestibule, Giotto's mosaic, la Navicella, is seen. Under the portico, opposite the great door, is Bernini's great bas relief representing Christ commanding Peter to feed his sheep; and at the ends of the portico are the equestrian statues of Constantine by Bernini, and of Charlemagne by Cornachini. The union of these masterpieces has an indescribable effect. The harmony and proportion which prevail in the interior of this august temple are such, that, immense as it is, the eye distinguishes all the parts without confusion or difficulty. When each object is minutely examined, we are astonished at its magnitude, so much more considerable than appears at first sight. The immense canopy of the high altar, supported by four bronze pillars of 120 feet in height, particularly attracts the attention. The dome is the boldest work of modern architecture. The cross thereon is 450 feet above the pavement. The lantern affords the most beautiful prospect of the city and the surrounding country. The splendid mosaics, tombs, paintings, frescos, works in marble, gilded bronze and stucco, the new sacristy—a beautiful piece of architecture, but not in unison with the rest—deserve separate consideration. The two most beautiful churches in Rome next to St. Peter's are the St. John's of the Lateran, and the Santa Maria Maggiore. The former, built by Constantine the Great, is the parochial church of the pope; it therefore takes precedence of all others, and is called Omnium urbis el orbis ecclesiarum mater et caput (the head and mother of all churches of the city and the world). In it is celebrated the coronation of the popes. It contains several pillars of granite, verde antico, and gilt bronze; the twelve apostles by Rusconi and Legros; and the beautiful chapel of Corsini, which is unequalled in its proportions, built by Alexander Galilei. The altar-piece is a mosaic from a painting by Guido, and the beautiful porphyry sarcophagus, which is under the statue of Clement XII., was found in the Pantheon, and is supposed to have contained the ashes of M. Agrippa. The nave of the church of Santa Maria Maggiore is supported by forty Ionic pillars of Grecian marble, which were taken from a temple of Juno Lucina: the ceiling was gilded with the first gold brought from Peru. We are here struck with admiration at the mosaics; the high altar, consisting of an antique porphyry sarcophagus; the chapel of Sixtus V., built from the designs of Fontana, and richly ornamented; the chapel of Paul V., adorned with marble and precious stones; the chapel of Sforza, by Michael Angelo; and the sepulchres of Guglielmo della Porta and Algardi. In the square before the front is a Corinthian column, which is considered a masterpiece of its kind. The largest church in Rome next to St. Peter's was the Basilica di San Paolo fuori delle Mura, on the road to Ostia, burnt a few years since. The church of S. Lorenzo, without the city, possesses some rare monuments of antiquity. The church of San Pietro in Vincola contains the celebrated statue of Moses, by Michael Angelo. The church of St. Agnes, in the place Navona, begun by Rainaldi and completed by Borromini, is one of the most highly ornamented, particularly with modern sculpture. Here is the admirable relief of Algardi, representing St. Agnes deprived of her clothes, and covered only with her hair. The Basilica of St. Sebastian, before the Porta Capena, contains the statue of the dying saint, by Giorgetti, a pupil of Algardi, and the master of Bernini. Under these churches are the catacombs, which formerly served as places of burial. In the church of St. Agnes, before the Porta Pia, among many other beautiful columns are four of porphyry, belonging to the high altar, and considered the most beautiful in Rome. In a small chapel is a bust of the Savior by Michael Angelo—a masterpiece. In the church of St. Augustine, there is a picture by Raphael representing the prophet Isaiah, and an Ascension by Lanfranco. The monastery has a rich library, called the Angelica, and increased by the library of cardinal Passionei. The following churches also deserve to be mentioned, on account of their architecture and works of art; the churches of St. Ignatius, St. Cecilia, S. Andrea della Valle, S.