Several examples of decoration illustrating this phase of Christian art occur in the wall paintings in the catacombs of S. Ponziano at Rome. The face of Christ in these representations is full of earnest and mild serenity; the right hand is raised as if in blessing, and the left holds the book of life. In the fourth century, mosaic was used in the basilicas as a means of decorating the apse and walls, as the Romans before had used it in their floors and dados. In the hands of the early and inexperienced artists, the character of the material in mosaic had a great deal to do, but not all, in the creating of the type of angular and rigid forms of the figures, which was transmitted to all subsequent Christian mosaics. At the same time there was the intense desire to make the figures of Christ and of other sacred personages of a sorrowful and austere character. We can, however, trace in these figures the magisterial dignity that invests the sculptured figures of the Emperors and Senators of Roman art. In Italy, the Christian mosaics assumed more and more a decided breaking away from the traditions of the antique. Large masses as single figures were symmetrically arranged, ornamental details were suppressed, and bands with inscriptions framed the large spaces of the walls and the apse. The figures were more isolated, attenuated, severe of expression, and leaving much to be desired in their anatomical construction or in the natural movement of the body; but all this tended to give them that expression of devotional simplicity aimed for by those early mystics, who only looked on the world as a “vale of tears.” In the vaulted roof of the funeral chapel erected to the memory of the daughter of Constantine at Rome—Sta. Costanza—some of the earliest mosaic work is to be found, consisting of an antique treatment of the vine and tendrils used in a symbolic sense; and in another chapel, that of the Empress Galla Placida, at Ravenna, similar work is seen, mixed with symbolic signs, as the hart—"panting for water brooks"—a symbol of the soul thirsting for salvation. This chapel was erected A.D. 440.