90 THE WORLIK 



nat moving- on uniformly with the stars. The middle bla,ck line 



represents the ecliptic and the whole space or belt is called the 

 Zodiac. The ancients divided the zodiac into twelve equal parts, 

 and gave them names, indicative of the peculiar employment of 

 that season of the year, when the sun happened to be in any one 

 of them. For example, the sun, in the preceding diagram, is in 

 the sign called Virgo, or the Virgin ; this sign was represented 

 by a virgin bearing sheaves of wheat, as the sun was near these 

 stars in the fall of the year, when the harvest was gathered. We 

 shall refer to this again when we explain the phenomena of the 

 seasons. The ecliptic was divided into twelve parts, or signs, 

 because the moon makes the complete circuit in one-twelfth of 

 the time the sun does, hence the twelfth of the year is called a 

 moon, or a month. The time of a lunation,, or interval from new 

 moon to new moon, being thirty days, and twelve of these luna- 

 tions happening In a year, the number of days to the year, when 

 reckoned by lunar months is 360. This number of days however 

 Is not strictly correct, for the sun makes 365^ revolutions appa- 

 rently, around the earth, while moving from any particular 

 star around to that star again. It would be inconvenient to sub- 

 divide the ecliptic into 365 parts as this number cannot be halved, 

 or quartered. So the early astronomers, adopting the lunar year, 

 divided the whole circle into 360 parts, which they called degrees. 

 This division, it will be understood from what we have said, was- 



