Such speculations are guess-work, but that the primitive religion of Persia was essentially monotheistic is an opinion which is likely to survive all attacks upon it. On less sure grounds stands the identification of that primitive religion with Zoroastrianism. The great authorities of a former generation, and amongst them my distinguished old friend, Professor Jules Oppert, believed that Cyrus was a Mazdean. But there is a good deal to support the view that Zoroastrianism did not become the State religion till the time of the Sásánians, who, as a new dynasty, grasped the political importance of having under them a strong and organised priesthood. Before that time the Magians seem to have been rather a sort of Salvation Army or Society of Jesus than the directors of a national Church. As late as the reign of Darius the Persians frequently buried their dead, a practice utterly repugnant to the Mazdean. Again, from Greek sources we know that the Persian kings sacrificed hecatombs of animals; thousands of oxen, asses, stags, &c., were immolated every day. Darius ordered one hundred bullocks, two hundred rams, four hundred lambs to be given to the Jews on the dedication of the new Temple (as well as twelve he-goats as sin-offerings for the twelve tribes) so that they might offer “sacrifices of sweet savours unto the God of heaven and pray for the life of the king and his sons.” Evidently Darius considered profuse animal sacrifices as a natural part of any great religious ceremony. Can it be supposed that such slaughter would have pleased a strict Zoroastrian? The Mazdeans retained the sacrifice of flesh as food: a small piece of the cooked meat eaten at table was included in the daily offering with bread, grain, fruits and the Homa juice, which was first drunk by the officiating priest, then by the worshippers, and finally thrown on the sacred fire. The small meat-offering was not animal sacrifice or anything at all like it. The Parsis substitute milk even for this small piece of meat, perhaps because the meat was usually beef, which would have caused offence to their Hindu fellow-citizens. I asked a Parsi High Priest who lunched with me at Basle during the second Congress for the History of Religions, what viands were eschewed by his community? He replied that they avoided both beef and the flesh of swine, but only out of respect for their neighbours’ rules: to them oil alone was forbidden—probably because of its virtue as a light-giver. In the Zoroastrian sacrifice it was never lost sight of that the outward act was but one of piety and obedience; the true sacrifice was of the heart: “I offer good thoughts, good words, good deeds.” It is hardly needful to say that the Mithraic taurobolium was in sheer contradiction to Mazdean law. Heretical sects were the bane of Zoroastrianism, and with one of these sprang up the strange practices which the Romans brought into Europe. Possibly its origin should be sought in some