THE CONSTELLATIONS 



its position in relation to the stars. The points on the 

 surface of the earth through which this imaginary axis 

 passes are called the poles'. If this axis were extended far 

 enough into space it would, at the present time, nearly 

 strike a star in the center of the northern heavens which we 

 call Polaris, or the North Star. 

 Due to certain causes, the 

 direction of the earth's axis 

 slowly changes so that it has 

 not always pointed so near to 

 Polaris as it now does. A 

 writer on astronomy reports 

 having visited an observatory 

 in China which was said to 

 be 4000 years old. In it were 

 placed originally two bronze 

 eye-holes on a slanting granite 

 wall for the purpose of sight- 

 ing the pole star of that era. 

 At the time of the astronomer's 

 visit in 1874, the line of sight 

 through these holes pointed to 

 a starless area in the sky. 



Polaris has, however, been the guiding-star of mariners 

 for a thousand years, and will remain so for thousands of 

 years to come. 



The Constellations. Probably the first careful watchers 

 of the sky were the shepherds of Asia. Just as we some- 

 times idly try to distinguish pictures in the glowing coals 

 of a fire, so they by stretches of imagination grouped the 

 stars into constellations that very roughly resembled animals 



MEDIEVAL IDEA OF THE 

 UNIVERSE 



From a fourteenth century manu- 

 script. Above the earth are the 

 clouds and the moon ; then the 

 rays of the sun ; next the' vari- 

 ous planets; above them the 

 stars; and finally the signs of 

 the zodiac. 



