The Mithraic worship was introduced into the western world, from Persia, about the time of Julius Cæsar, and speedily spread over all parts of the empire. It appears to have outlived other forms of idolatry in Europe. Its favourers seem to have abandoned polytheism; on the line of the Wall at least, the name of Mithras is not combined with that of any other deity. This circumstance, together with the laborious, though vain, researches of its philosophical supporters, recommended it to those who rejected the pure and simple truths of Christianity. [Sidenote: MITHRAIC CAVE.] Another of the Housesteads altars to Mithras is here figured. It is inscribed— [Illustration] D[EO] O[PTIMO] M[AXIMO] INVICTO MYT RÆ SAECVLARI PVBL[IVS] PROCVLI NYS C[ENTVRIO] PRO SE ET PROCVLO FIL[IO] SVO V. S. L. M. ——— D.D. (_dominis_) N.N. (_nostris_) GALLO ET VOLVSINO CO[N]S[VLIBVS] CC To the god best and greatest The invincible Mith- ras, lord of ages, Publius Proculinus, Centurion, for himself And Proculus his son, his vow freely and deservedly pays. ——— Our lords Gallus and Volusinus being consuls. The temples of Mithras generally consisted of a cave, or a small building from which the light was excluded. A cave was adopted, ‘because,’ says Porphyry, ‘a cave is the image and symbol of the world,’ and it was dark, ‘because the essence of the virtues is obscure.’ All who sought the favour of this god were subjected to a long course of painful initiatory discipline. Nonnius, a Greek poet, says— [Sidenote: MITHRAIC RITES.] No one can be admitted into his mysteries, unless he has previously undergone all the punishments, the number of which they say is eighty, some of them of the gentler sort, others more severe. The milder are undergone first, then the severer; and after the whole course is gone through, they are initiated. Fire and water are the sorts of punishment which they endure. These torments are said to be inflicted to produce examples of piety and greatness of mind under sufferings. After they have been many days in water, they cast themselves into fire; then live in desert places, and there subdue the cravings of hunger; and thus, as we have said, the aspirant goes through the whole course of eighty torments; which if he survive, then he is initiated into the mysteries of Mithras.