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NATURE-STUDY REVIEW 



[17:1— Jan., 1921 



Eclipse of the moon Dec. i6, 1899 



Four stages photographed by Verne Morton 



AN ECLPSE OF THE MOON 



It is only when the moon is full that it may enter eclipse, because 

 at that time the sun is shining upon the opposite side of our earth 

 and the moon is on the side of its orbit farthest away from the sun 

 so that the earth in passing between it and the sun casts its shadow 

 upon it. Since the moon has no light to shine with except what it 

 gets from- the sun, it ceases to shine when it passes into our shadow. 

 At first a portion of the eastern edge of the moon becomes dim and 

 then disappears; gradually the shadow creeps over the moon's 

 bright face and finally hides it, but not entirely, for we can still 

 see it faintly glowing with a ruddy light; this is caused by the 

 refraction of the sim's rays through our atmosphere which absorbs 

 the green and blue rays so that for a time the moon is bathed in 

 sunset glow. Joel, the Prophet declared "The sun shall be turned 

 to darkness and the moon into blood." If one could be stationed 



