BOOK II. XVIII. 82-xx. 84 



arduous study of the heavens, that what when they 

 fall to earth are termed thunderbolts are the fires of 

 the three upper planets, particularly those of Jupiter, 

 whieh is in the middle position — possibly because it 

 voids in this way the charge of excessive moisture 

 from the upper circle (of Saturn) and of excessive 

 heat from the cii-cle below (of Mars); and that this 

 is the origin of the myth that thunderbolts are the 

 javelins hurled by Jupiter. Consequently heavenly 

 fire is spit forth by the planet as crackhng charcoal 

 flies from a burning log, bringing prophecies with it, 

 as even the part of himself that he discards does not 

 cease to function in its divine tasks. And this is 

 accompanied by a very great disturbance of the air, 

 because moisture collected causes an overflow, or 

 because it is disturbed by the birth-pangs so to speak 

 of the planet in travail. 



XIX. Many people have also tried to discover Distanees o 

 the distances of the planets from the earth, and have ' p^"**** 

 given out that the distance of the sun from the moon 



is 19 times that of the moon itself from the earth. 

 The penetrating genius of Pythagoras, however, 

 inferred that the distance of the moon from the 

 earth was 15,750 miles," and that of the sun from the 

 moon twice that figure, and of the sun from the 

 twelve signs of the Zodiac three times. Our fellow- 

 countiyman Sulpicius Gallus also held this view. 



XX. But occasionally Pythagoras draws on the TMr 

 theory of music, and designates the distance between rat^l'""* 

 the earth and the moon as a whole tone, that between 



the moon and Mercury a semitone, between Mercury 

 and Venus the same, between her and the sun a tone 

 and a half, between the sun and Mars a tone (the 

 same as the distance between the earth and the 



227 



