[Illustration: Ancient Candelabrum in the church of SS. Nereo ed Achilleo.] In the next chapter I shall speak of ancient temples as museums of statuary, galleries of pictures, and cabinets of precious objects. I need not describe the acceptance and development of this tradition by the Church. To it we are indebted for the inexhaustible wealth in works of art of every kind, of which Italy is so proud. But in the period which elapsed between the fall of the empire and the foundation of the Cosmati school, the Christians were compelled, by the want of contemporary productions, to borrow works of art and decorative fragments from temples, palaces, and tombs. The gallery of the Candelabra, in the Vatican museum, has been formed mostly of specimens formerly set up in churches. The accompanying cut represents the candelabrum still existing in the church of SS. Nereo ed Achilleo, one of the most exquisite and delicate works of the kind. The Biga, or two-horse chariot, in the Vatican, was used for centuries as an episcopal throne in the choir of S. Mark's. In the church of the Aracœli there was an altar dedicated to Isis by some one who had returned safely from a perilous journey. This bore the conventional emblem of two footprints, which were believed by the Christians to be the footprints of the angel seen by Gregory the Great on the summit of Hadrian's tomb. Philip de Winghe describes them as those of a _puer quinquennis_, a boy five years old.[18] This curious relic has been removed to the Capitoline Museum. The indifference with which these profane and sometimes offensive works were admitted within sacred edifices is astonishing. The high altar in the church of S. Teodoro was supported, until 1703, by a round _ara_, on the rim of which the following words are now engraved: "On this marble of the gentiles incense was offered to the gods." Another altar, in the church of S. Michele in Borgo, was covered with bas-reliefs and legends belonging to the superstition of Cybele and Atys; a third, in the church of the Aracœli, had been dedicated to the goddess Annona by an importer of wheat. The pavement of the basilica of S. Paul was patched with nine hundred and thirty-one miscellaneous inscriptions; and so were those of S. Martino ai Monti, S. Maria in Trastevere, SS. Giovanni e Paolo, etc. We have one specimen left of these inscribed pavements in the church of SS. Quattro Coronati on the Cælian, which may be called an epigraphic museum. [Illustration: The Templum Sacræ Urbis (SS. Cosma e Damiano).]