CHAPTER FOUR 



THE STARRY HEAVENS 



The snow-white clouds, whose fleecy wings unfold 

 The stars, that light your boundless breadth of blue, 

 Roll back your edges, tinged with deepest gold, 

 And softly let the peaceful wanderers through ; 

 Till, one by one, they burst upon my eyes, 

 O'ertaking my young heart with sudden sweet surprise. 



PRINCESS AMELIA 



Go out and view the heavens at night. Like a great 

 bowl or hemisphere dotted with twinkling points of 

 light, the heavens appear above you. The other half 

 of the sphere is invisible to you, but you can think of 

 a great hollow sphere called the celestial sphere, within 

 which is the little sphere we call the earth. Standing 

 upon the earth, you are viewing the celestial sphere 

 from the inside. 



Look up at the sky and think what is meant by the 

 celestial sphere. Is it at any definite distance from us, 

 and is it like a wall with a certain thickness that shuts 

 us in? Or do the words " celestial sphere " describe 

 what we seem to see rather than what actually exists 

 in space about us? 



Horizon, zenith, and altitude. The line where the 

 earth and sky seem to meet is the horizon. The eleva- 

 tion of a star above the horizon is its altitude. The point 

 in the heavens directly overhead is the zenith. If a 

 star is at the zenith, its altitude is 90 degrees, for there 

 are 360 degrees in a circle and the zenith is one fourth 

 of the way around the celestial sphere from the horizon 

 to the starting point on the horizon. If a star is midway 

 between the zenith and the horizon, its altitude is 45 



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