BOOK II. XIII. 66-69 



the whole of its breadth, but without going at all 

 outside it. The planet Mercury diverges very widely 

 from these, but without wandering over more than 

 8 of the 12 degrees of latitude of the zodiac, and 

 these 8 not uniformly but two in the middle of the 

 zodiac, four above it and two below it. Then the 

 sun travels unevenly in the middle of the zodiac 

 between the two halves with a wavy serpentine 

 course, the planet Mars over 4 degrees in the middle, 

 Jupiter one in the middle and two above it, Saturn 

 two like the sun. This will be the principle of the 

 latitudes of the planets when setting towards the 

 South or rising towards the North. Most people 

 have supposed that with this system agrees also the 

 third mentioned above," that of their rising from the 

 earth to the sky, and that this ascent also is made 

 simultaneously ; but this is a mistake. To refute 

 them it is necessary to develop an extremely abstruse 

 argument that embraces all the causes mentioned. 



It is agreed ^ that the planets are nearest to the earth (2)jn reia/(or 

 in both altitude and latitude at their evening setting, '" "^ ^'"^'''" 

 and that their morning risings occur at the beginning 

 of both altitude and latitude, while their stations 

 occur in the middle sections of the altitudes, called 

 ' ecliptics.' It is similarly admitted "^ that their 

 velocity increases as long as they are in the neigh- 

 bourhood of the earth and decreases when they 

 withdraw fi*om it to a height : this theory is specially 

 supported by the apogees of the moon. It is equally 

 undoubted '^ that the three higher ones * moreover 

 increase their motion in their morning risings and 

 diminish it from their first (morning) stations to their 

 second (evening) stations. In view of these facts it 

 will be evident that the latitudes are ascended from 



215 



