THE FIRST KHALIF. Mohammed's life had been almost entirely consumed in the conversion or conquest of his native country. Toward its close, however, he felt himself strong enough to threaten the invasion of Syria and Persia. He had made no provision for the perpetuation of his own dominion, and hence it was not without a struggle that a successor was appointed. At length Abubeker, the father of Ayesha, was selected. He was proclaimed the first khalif, or successor of the Prophet. There is a very important difference between the spread of Mohammedanism and the spread of Christianity. The latter was never sufficiently strong to over throw and extirpate idolatry in the Roman Empire. As it advanced, there was an amalgamation, a union. The old forms of the one were vivified by the new spirit of the other, and that paganization to which reference has already been made was the result. THE MOHAMMEDAN HEAVEN. But, in Arabia, Mohammed overthrew and absolutely annihilated the old idolatry. No trace of it is found in the doctrines preached by him and his successors. The black stone that had fallen from heaven--the meteorite of the Caaba--and its encircling idols, passed totally out of view. The essential dogma of the new faith--"There is but one God"--spread without any adulteration. Military successes had, in a worldly sense made the religion of the Koran profitable; and, no matter what dogmas may be, when that is the case, there will be plenty of converts. As to the popular doctrines of Mohammedanism, I shall here have nothing to say. The reader who is interested in that matter will find an account of them in a review of the Koran in the eleventh chapter of my "History of the Intellectual Development of Europe." It is enough now to remark that their heaven was arranged in seven stories, and was only a palace of Oriental carnal delight. It was filled with black-eyed concubines and servants. The form of God was, perhaps, more awful than that of paganized Christianity. Anthropomorphism will, however, never be obliterated from the ideas of the unintellectual. Their God, at the best, will never be any thing more than the gigantic shadow of a man--a vast phantom of humanity--like one of those Alpine spectres seen in the midst of the clouds by him who turns his back on the sun. Abubeker had scarcely seated himself in the khalifate, when he put forth the following proclamation: In the name of the most merciful God! Abubeker to the rest of the true believers, health and happiness. The mercy and blessing of God be upon you. I praise the most high God. I pray for his prophet Mohammed. INVASION OF SYRIA. "This is to inform you that I intend to send the true believers into Syria, to take it out of the hands of the infidels. And I would have you know that the fighting for religion is an act of obedience to God."