LIGHT SCIENCE 

 FOR LEISURE HOURS. 



THIRD SERIES. 



GREAT SOLAR ECLIPSES. 



AMONG the total eclipses recorded during historic times, 

 there are some which stand out among the rest on 

 account either of their magnitude or of the historical 

 interest associated with them. I propose to give a 

 brief account of the more remarkable solar eclipses 

 whose records have been preserved. Before doing so, 

 however, it may be well to point out the circumstances 

 on which the magnitude of a solar eclipse depends ; 

 and to explain why it is that so few eclipses occur 

 which deserve to be ranked among great total eclipses. 

 The average apparent dimensions of the sun exceed 

 those of the moon. But both bodies vary in apparent 

 magnitude the moon more than the sun. Perhaps 

 many of my readers will be surprised to learn that we 

 receive fully one-fourth more light from some full 

 moons than from others, owing to the variation of her 

 apparent magnitude. Accordingly, when she is at her 

 largest and the sun at his smallest, she is able to hide 



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