$; i2, i 3 ] The Constellations: the Zodiac 13 



memory can follow them ; bears, lions, and fishes, large and 

 small, confuse all nomenclature." (Outlines of Astronomy^ 



3 T -) 



The constellations as we now have them are, with the 

 exception of a certain number (chiefly in the southern 

 skies) which have been added in modern times, substantially 

 those which existed in early Greek astronomy ; and such 

 information as we possess of the Chaldaean and Egyptian 

 constellations shews resemblances indicating that the Greeks 

 borrowed some of them. The names, as far as they are 

 not those of animals or common objects (Bear, Serpent, 

 Lyre, etc.), are largely taken from characters in the Greek 

 mythology (Hercules, Perseus, Orion, etc.). The con- 

 stellation Berenice's Hair, named after an Egyptian queen 

 of the 3rd century B.C., is one of the few which com- 

 memorate a historical personage.* 



13. Among the constellations which first received names 

 were those through which the sun passes in its annual 

 circuit of the celestial sphere, that is those through which 

 the ecliptic passes. The moon's monthly path is also a great 

 circle, never differing very much from the ecliptic, and the 

 paths of the planets ( 14) are such that they also are never 

 far from the ecliptic. Consequently the sun, the moon, 

 and the five planets were always to be found within a region 

 of the sky extending about 8 on each side of the ecliptic. 

 This strip of the celestial sphere was called the zodiac, 

 because the constellations in it were (with one exception) 

 named after living things (Greek <3ov, an animal) ; it was 

 divided into twelve equal parts, the signs of the zodiac, 

 through one of which the sun passed every month, so that 

 the position of the sun at any time could be roughly 

 described by stating in what " sign " it was. The stars in 

 ench " sign " were formed into a constellation, the " sign " 

 and the constellation each receiving the same name. Thus 



* I have made no attempt either here or elsewhere to describe the 

 constellations and their positions, as I believe such verbal descrip- 

 tions to be almost useless. For a beginner who wishes to become 

 familiar with them the best plan is to get some better informed 

 friend to point out a few of the more conspicuous ones, in different 

 parts of the sky. Others can then be readily added by means of a 

 star-atlas, or of the star-maps given in many textbooks. 



