As this is not an architectural dissertation, but merely a tracing of the work of this great guild, I will keep more to the inscriptions relative to Magistri, than to a description of their works, which has been done by so many writers.
In the old times before the painters and sculptors, and after them the metal-workers, split off and formed companies of their own, every kind of decoration was practised by the Masters. A church was not complete unless it were adorned in its whole height and breadth with either sculpture, mosaic, or paintings, and this from the very early times of Constantine and his Byzantine mosaicists, and of Queen Theodolinda and her fresco-painters, up to the revival of mosaics by the Cosmati, and the fresco-painting in the Tuscan schools. But never were those arts entirely lost.
The ideas which the Lombard architects brought up from Sicily, when working there under the Normans, were the seeds of re-vivification, and caused a tremendous evolution in the art of the guild. They saw the decorative value of mosaic as it was used in the twisted Saracenic columns, and they were charmed by the rich use of sculpture in the graceful arches. From that time, every lodge throughout the land seemed to invent a new style peculiar to itself.
The Romans, with their traditions of classic mosaics, revived the art in Saracenic style as a means of decoration. The Tuscans, with their wealth of coloured marbles, enlarged chromatic decoration into chromatic architecture, and their airy towers and arched churches were all more or less polychrome. The Lombards, having no marbles at hand, took from these same Saracens their rich traceries and cuspings, which they produced in the plastic clay, throwing a veil of ruddy beauty over the façades and arches of their buildings.
The name of the Cosmati family has become generic for the peculiar chromatic sculpture of Rome in the twelfth century; the family were complete masters of the art. But though they may have taken the idea of its revival as a decorative aid to sculpture, it was by no means their invention, or even their monopoly. If you look at a Cosmati pillar or panel, and then at the floor of any Roman church, you will see that Cosmatesque decoration is but an adaptation of the old Roman opus Alexandrinum. And we have plenty of proof of the fact that other Magistri of the guild also practised it. The ambone in S. Cesareo in Palatio at Rome, of which we give an illustration, is earlier than any of Cosimo's family.
Basilica of S. Paolo fuori le mura, Rome.
There exists at Florence (in S. Leonardo) the ancient pulpit from S. Piero Scheraggio, and which was said to have been brought there from Fiesole. Its date is supposed to be before 1000 A.D. Though of a ruder style, we have the Cosmatesque inlaying of glass and marble, as a setting to sculptures distinctly Comacine, and of almost Longobardic antiquity. In Sta. Maria in Cosmedin are two fine pulpits, on one of which is a beautiful candlestick formed of a twisted column, inlaid in the same style. The Comacine lion crouches beneath it, and on the base is the inscription in Gothic letters, telling us that the worthy and learned man Paschalis (called Rita), with great study made this candlestick.[290] Then we have Nicolao di Rannuncio, whose name is inscribed on the door of inlaid marble in the church of S. Maria at Toscanella,[291] and a whole family whose names are inscribed on the ciborium of S. Lorenzo fuori le Mura:[292] where it is written—"John, Peter, Angelo, and Sasso, sons of Paul the sculptor, Magisters of this Opera. I, the humble Abbot Hugh, had this work executed"[293] (Johs, Petrus, Angĕs, et. Sasso. Filii. Pauli. Marmōr. Huj'. Opis. Magister Fuer. Ann d. M. CXLVIII. Ego. Hugo. Humilis. Abbs. Hoc. Opus. Fieri Feci.). The tabernacle is of the usual four-pillared form; the columns are ancient porphyry ones adapted; the capitals the usual Comacine mixture of classic and mediæval—acanthus leaves and cornucopiæ with the mystic beasts climbing among them.