The Sun 219 



to them to go down into the western ocean and, some 

 hours later, to come up in the east. We still say that 

 the sun rises and sets. 



When looking out of the window of a train at another 

 train standing on a track at one side, have you ever 

 found yourself unable to tell, when one of the trains 

 started, whether it was the one you were on or the other 

 one that was moving? The sun moves across the sky, 

 from east to west, sets, and appears again in the east. 

 How do you explain this apparent motion ? 



Eclipses of the sun. A total eclipse of the sun is an 

 event long to be remembered. Around the sun may 

 then be seen the beautiful corona and wonderful pro- 

 jections of light, like great tongues of flame, 5000 to 

 100,000 miles in length. Stars become visible, chickens 

 go to roost, bats fly about, ignorant persons become 

 terrified. Civilized peoples are able to predict when 

 the darkening of the sun and moon will occur, but 

 savages are always awed by the wisdom of the stranger 

 who is able to foretell these events. 



Frequency and duration of eclipses. Few persons 

 witness a total eclipse of the sun more than once or twice 

 in a lifetime unless they go purposely to the regions 

 where astronomers have calculated that the eclipses will 

 be total. Total eclipses may be seen oftener in the 

 tropics than in high latitudes. Most persons in this 

 country have probably never had an opportunity to 

 witness a total eclipse of the sun ; that is, to be where 

 the moon completely hid the sun from their view. 

 Seven total eclipses may be witnessed in the United 

 States in the present century. One of them occurred on 



