ITS EARLIEST STAGES. 157 



was supposed to turn about the visible pole and 

 another pole opposite to this, and these poles were 

 connected by an imaginary Axis. The circle which 

 divided the sphere exactly midway between these 

 poles was called the Equator (to-^e pivos) . The 

 two circles parallel to this which bounded the 

 sun's path among the stars were called Tropics 

 (rpoTTiKai), because the sun turns back again towards 

 the equator when he reaches them. The stars 

 which never set are bounded by a circle called 

 the Arctic Circle (ap/cn/co?, and apKTos, the Bear, 

 the constellation to which some of the principal 

 stars within that circle belong). A circle about 

 the opposite pole is called Antarctic, and the stars 

 which are within it can never rise to us 41 . The 

 sun's path or circle of the signs is called the 

 Zodiac, or circle of animals ; the points where this 

 circle meets the equator are the Equinoctial Points, 

 the days and nights being equal when the sun is 

 in them ; the Solstitial Points are those where the 

 sun's path touches the tropics; his motion to the 

 south or to the north ceases when he is there, 

 and he appears in that respect to stand still. The 

 Colures (KoXovpoi, mutilated) are circles which pass 



t through the poles and through the equinoctial 

 and solstitial points; they have their name because 

 they are only visible in part, a portion of them 

 being below the horizon. 



41 The Arctic and Antarctic Circles of modern astronomers 

 are different from these. 



