But how are we to account for the presence of this pagan monument within the limits of a Christian cemetery? There are two things to be 218 observed, says M. Perret, in explanation of this circumstance. First, the _arcosolium_ is not exclusively Christian in character. M. de Saulcy has given examples of several Jewish and pagan tombs in the form of _arcosolia_.[345] In the second place, there is nothing strange in a family practising an oriental rite, like the worship of Mithras--which with the Phrygian and Isiac mysteries were widely prevalent in Rome in the early Christian centuries--having a private place of sepulture, as this seems to have been. It is situated near the Appian Way, from which there was probably a separate entrance. Near by is a pagan _columbarium_ which now forms one of the entrances of the Catacomb, of which it seems part equally with the gallery containing this tomb. This space may possibly have been originally usurped from the Christian cemetery; but it is more probable that the gallery and tomb were independently constructed, and that the fossors came unexpectedly upon it in their excavations. This conjecture is confirmed by the indications of its having been subsequently shut off, but the obstructions have long since been removed. It is impossible to admit that the Christians, in contempt of the sacred usages of the primitive ages, have commingled their sepulchres with those of the pagans.[346] But Christian art, though affected by pagan influence, did not servilely follow pagan types. It introduced new forms to express new ideas, or employed existing forms with a new significance; just as Christianity itself introduced new words, or gave new meanings to old ones, not only in the classic tongues but in every language which it has adopted as the vehicle of its sublime truths. It created a cycle of symbolical types of especial Christian significance; and became 219 more enriched and enlarged in its scope by allegorical representations of religious doctrine, and by illustrations of Old and New Testament history and miracles. But Christian art soon lost that freedom of treatment which it inherited from its classic parentage, and fell into fixed and conventional forms, which were endlessly reiterated. “Before many years,” says Maitland, “the empire of imagination passed away, and the genius of art, with ‘torch extinct and swimming eye,’ had to mourn over the introduction of the hieratic style which, wherever it has appeared throughout the world, has cramped and almost annihilated the inventive faculty.” Like the hieroglyphs of Egypt and of India, or like the picture-writing of the lost races of Central America, though in a less degree, the objects of Christian art became not so much representative as symbolic. Individual genius can only struggle hopelessly with the shackles of a conventional system. From the freedom of nature it sinks into a servile copyism which can hardly be called art at all.