This idea of a first mover turning the heavens round in twenty-four hours with an impossible motion, and of the sun, though acted upon by this first motion, yet imperceptibly advancing from west to east by a motion peculiar to itself, and without a cause, would but embarrass a young beginner. It is sufficient for him to know that, whether the earth revolves on its own axis and round the sun, or the sun completes his revolution in a year, appearances are nearly the same, and that, in astronomy, we are obliged to judge of things by our eyes before we examine them as natural philosophers. He will soon know the cause of the eclipses of the sun and the moon, and why they do not occur every night. It will at first appear to him that, the moon being every month in opposition to and in conjunction with the sun, we should have an eclipse of the sun and one of the moon every month. But when he finds that these two luminaries are not in the same plane and are seldom in the same line with the earth, he will no longer be surprised. He will easily be made to understand how it is that eclipses have been foretold, by knowing the exact circle in which the apparent motion of the sun and the real motion of the moon are accomplished. He will be told that observers found by experience and calculation the number of times that these two bodies are precisely in the same line with the earth in the space of nineteen years and a few hours, after which they seem to recommence the same course; so that, making the necessary allowances for the little inequalities that occurred during those nineteen years, the exact day, hour, and minute of an eclipse of the sun or moon were foretold. These first elements are soon acquired by a child of clear conceptions. Not even the precession of the equinoxes will terrify him. It will be enough to tell him that the sun has constantly appeared to advance in his annual course, one degree in seventy-two years, towards the east; and this is what Ovid meant to express: _"Contrarius evehor orbi"_;--"Marching secure in my opposing path." Thus the Ram, which the sun formerly entered at the beginning of spring, is now in the place where the Bull was then. This change which has taken place in the heavens, and the entrance of the sun into other constellations than those which he formerly occupied, were the strongest arguments against the pretended rules of judicial astrology. It does not, however, appear that this proof was employed before the present century to destroy this universal extravagance which so long infected all mankind, and is still in great vogue in Persia. A man born, according to the almanac, when the sun was in the sign of the Lion, was necessarily to be courageous; but, unfortunately, he was in reality born under the sign of the Virgin. So that Gauric and Michael Morin should have changed all the rules of their art.