of the year, and how many circulations make up the great year of every planet.

the year of saturn is completed when he has had his circulation in the space of thirty solar years; of jupiter in twelve; of mars in two, of the sun in twelve months; in so many mercury and venus, the spaces of their circulation being equal; of the moon in thirty days, in which time her course from her prime to her conjunction is finished. as to the great year, some make it to consist of eight years solar, some of nineteen, others of fifty-nine. heraclitus, of eighteen thousand. diogenes, of three hundred and sixty-five such years as heraclitus assigns. others there are who lengthen it to seven thousand seven hundred and seventy-seven years.