This planning of a Jewish calendar by which the Festivals were computed perpetually and yet kept in their natural seasons, was a wonderful piece of astronomical and arithmetical ingenuity. For a lunar year of twelve months is shorter than a solar year of three-hundred and sixty-five and a quarter days. To average the difference and thus prevent, for example, Passover eventually occurring in Autumn and Tabernacles in Spring, an additional month (second Adar) was added seven times in every nineteen years. Further, the calendar had to be so devised that certain Festivals should not fall on undesirable days--for example to prevent the Day of Atonement falling on Friday or Sunday. This ancient calendar is still our guide for the Jewish year. CHAPTER XXXIV. THE DIVISION OF THE ROMAN EMPIRE. Julian. But a brief check was made on Christian advance and its pitiless attempt to suppress Judaism in the coming to the throne of Julian in 361. For this emperor did not endorse the new religion, but accepted the old Roman cult of the Pantheon, though in its most idealized form, preferring to purify instead of abolishing it. But it was too late; it had been weighed in the balance and found wanting. Julian, whom the Church styled "the Apostate," was both tolerant and philanthropic, and a man who fostered learning. As between Christianity and Judaism, though bred in the former, to which he continued to grant perfect freedom of observance, his inclination turned rather toward the latter, and he held it in high esteem. He removed the restrictive laws and special taxes against Judaism, imposed by his predecessors. He even took steps for the rebuilding of the Temple at Jerusalem. The Jews were transported with delight and began at once sending contributions toward its erection with greater zeal than was even shown, according to Scripture, by that generation in the wilderness in their gifts toward the Tabernacle. The Christians looked on with consternation, and regarded every unfavorable interruption as the miraculous intervention of heaven. Not a supposed miracle however, but a real event, brought the project to nought. Julian died on the battlefield. Two Roman Empires.