There are further considerations which show that the Babylonians could not have given these planetary names to the days of the week. The order of the names implies that a twenty-four hour day was used, but the Babylonian hours were twice the length of those which we use; hence there were only twelve of them. Further, the Babylonian week was not a true week running on continuously; it was tied to the month, and hence did not lend itself to such a notation. But the order adopted for the planets is that current amongst the Greek astronomers of Alexandria, who did use a twenty-four hour day. Hence it was certainly later than 300 B.C. But the Greeks and Egyptians alike used a week of ten days, not of seven. How then did the planetary names come to be assigned to the seven-day week? It was a consequence of the power which the Jews possessed of impressing their religious ideas, and particularly their observance of the sabbath day, upon their conquerors. They did so with the Romans. We find such writers as Cicero, Horace, Juvenal and others remarking upon the sabbath, and, indeed, in the early days of the Empire there was a considerable observance of it. Much more, then, must the Alexandrian Greeks have been aware of the Jewish sabbath,--which involved the Jewish week,--at a time when the Jews of that city were both numerous and powerful, having equal rights with the Greek inhabitants, and when the Ptolemies were sanctioning the erection of a Jewish temple in their dominions, and the translation of the Jewish Scriptures into Greek. It was after the Alexandrian Greeks had thus learned of the Jewish week that they assigned the planets to the seven days of that week, since it suited their astrological purposes better than the Egyptian week of ten days. That allotment could not possibly have brought either week or sabbath into existence. Both had been recognized many centuries earlier. It was foisted upon that which had already a venerable antiquity. As Professor Schiaparelli well remarks, "we are indebted for these names to mathematical astrology, the false science which came to be formed after the time of Alexander the Great from the strange intermarriage between Chaldean and Egyptian superstitions and the mathematical astronomy of the Greeks."[139:1] There is a widespread notion that early astronomy, whether amongst the Hebrews or elsewhere, took the form of astrology; that the fortune-telling came first, and the legitimate science grew out of it. Indeed, a claim is not infrequently made that no small honour is due to the early astrologers, since from their efforts, the most majestic of all the sciences is said to have arisen.