1Those men showed me the other course, that of the moon, twelve great gates, crowned from west to east, by which the moon goes in and out of the customary times.
2It goes in at the first gate to the western places of the sun, by the first gates with (thirty)-one (days) exactly, by the second gates with thirty-one days exactly, by the third with thirty days exactly, by the fourth with thirty days exactly, by the fifth with thirty-one days exactly, by the sixth with thirty-one days exactly, by the seventh with thirty days exactly, by the eighth with thirty-one days perfectly, by the ninth with thirty-one days exactly, by the tenth with thirty days perfectly, by the eleventh with thirty-one days exactly, by the twelfth with twenty-eight days exactly.
3And it goes through the western gates in the order and number of the eastern, and accomplishes the three hundred and sixty-five and a quarter days of the solar year, while the lunar year has three hundred fifty-four, and there are wanting (to it) twelve days of the solar circle, which are the lunar epacts of the whole year.
4Thus, too, the great circle contains five hundred and thirty-two years.
5The quarter (of a day) is omitted for three years, the fourth fulfills it exactly.
6Therefore they are taken outside of heaven for three years and are not added to the number of days, because they change the time of the years to two new months towards completion, to two others towards diminution.
7And when the western gates are finished, it returns and goes to the eastern to the lights, and goes thus day and night about the heavenly circles, lower than all circles, swifter than the heavenly winds, and spirits and elements and angels flying; each angel has six wings.
8It has a sevenfold course in nineteen years.