334 LIGHT SCIENCE FOR LEISURE HOURS. 



My theory, then, respecting the Shield of Achilles 

 is this : 



I conceive that Homer, in his Eastern travels, 

 visited imposing temples devoted to astronomical ob- 

 servation and star-worship ; and that nearly every 

 line in both " shields " is borrowed from a poem in 

 which he described a temple of this sort, its domed 

 zodiac, and those illustrations of the labors of differ- 

 ent seasons and of military or judicial procedures 

 which the astrological proclivities of star-worshippers 

 led them to associate with the different constellations. 



I think there are arguments of some force to be 

 urged in support of this theory, fanciful as it may 

 seem. 



In the first place, it is necessary that the constella- 

 tions recognized in Homer's time (not necessarily, or 

 probably, l>y Homer) should be distinguished from 

 later inventions. 



Aratus, writing long after Homer's date, mentions 

 forty-five constellations. These were probably derived, 

 without exception, from the globe of Eudoxus. Re- 

 membering the tendency which astronomers have 

 shown, in all ages, to add to the list of constellations, 

 we may assume that in Homer's time the number 

 was smaller. Probably there were some fifteen north- 

 ern and ten southern constellations, besides the twelve 

 zodiacal signs. The smaller constellations mentioned 

 by Aratus doubtless formed parts of larger figures. 



