220 Trees, Stars, and Birds 



FlG. 135. Photograph of sun taken during an eclipse. 



June 8, 1918, along a track from Oregon to Florida. 

 Others will occur September 10, 1923 ; January 24, 

 1925 ; and August 31, 1932. 



An eclipse of the sun remains total for less than 8 

 minutes, often for only 2 or 3 minutes. But the sun 

 is partly hidden for an hour or two before and after the 

 brief period during which it is entirely hidden. 



Cause of eclipses of the sun. The sun is eclipsed by 

 the moon passing between it and the observer. It may 

 be eclipsed for observers at some places, while those on 

 a distant part of the earth can see all of it. If it is totally 

 eclipsed, it will appear so only to observers along a 

 narrow belt of the earth. Those on either side of this 

 belt will see a partial eclipse. You can understand why 

 this is by using a globe to represent the sun and a 

 smaller globe, or large ball, for the moon. You can get 

 behind the smaller globe in such a way that it would 

 prevent your seeing any part of the larger one. By 

 moving slightly you can see a part of the large globe, 

 and by moving farther, you can see all of it. Thus you 

 see that to people differently located on the earth an 

 eclipse of the sun appears different. 



