BOOK II. XIV. 74-xv. 77 



proximity to the centre does in the case of the 

 former ; the former begin to decelerate from their 

 morning setting, but the latter to accelerate. The 

 former travel backward from their morning to their 

 evening station, the planet Venus from her evening 

 to her morning station. But she begins to chmb her 

 latitude after her morning rise, but after her morning 

 station to ascend her altitude and foUow the sun, 

 being swiftest and highest at her morning setting; 

 whereas she begins to descend in latitude and 

 decelerate after her evening rising, and to turn back 

 and simultaneously to descend in altitude after her 

 evening station ; on the other hand the planet 

 Mercury begins to chmb in both ways after his 

 morning rising, but after his evening rising to 

 descend in latitude, and following the sun at an 

 Interval of 15 degrees he stands motionless for almost 

 four days. Afterwards he descends from his altitude 

 and proceeds back from his evening setting to his 

 morning rise. And only this planet and the moon 

 set in as many days as they have risen in ; Venus 

 ascends in 15 times as many days as she sets in, 

 while Saturn and Jupiter descend in twice as many, 

 and Mars in actually four times as many. So great 

 is the variety of nature ; but the reason is evident — • 

 bodies that strain up into the heat of the sun also have 

 difficulty in desccnding. 



XV. Many more facts can be produced about other 

 these mysteries of nature and the laws that she particviar 

 obeys — for example, in the case of the planet ^'^^"^* '" '' 

 Mars (whose course it is very difficult to observe) 

 that it never makes its station with Jupiter at an 

 angle of 120 , and very seldom with Jupiter separ- 

 ated 60^ (whioh amounts to ^th of the celestial 



