Elements of Astronomy (Alfraganus) (1669) - Page 18


	—nor does it rise for several months after it has set.	24
VIII.	On the dimension of the earth, and the division of the habitable world into seven climates.	30
IX.	The names of the more celebrated regions and cities are provided, which the individual climates of the world encompass.	35
X.	On the ascensions of the signs, and their variety in right and oblique spheres.	39
XI.	On the quantity of diurnal and nocturnal time; and the difference between equal and unequal hours.	42
XII.	The figure and composition of the star-bearing orbs are described, and the orders of their distances from the earth.	45
XIII.	By what method the Sun, the Moon, and the fixed stars are turned in their orbs toward both directions, east and west; which is called motion in longitude.	49
XIV.	The motions of the five wandering stars i.e., the planets are described in their orbs according to longitude.	55
XV.	On the regression of the five wandering stars in the Zodiac.	61
XVI.	What relationship the orbs of the stars, which are called epicycli epicycles, have to the eccentric orbs; and how far the centers of the eccentrics are distant from the center of the earth.	64
XVII.	On the periodic revolutions of the stars through their orbs, and through the Zodiac.	65
XVIII.	The motions of the fixed and wandering stars are described in both directions, north and south; which are called motions in latitude.	67