CHAPTEK XIX. 
TWO GREAT LIGHTS. 
The sun regulates not only our seasons but even 
our “ sitting down and our rising up.” Our homes 
move about him year after year, obedient to his call. 
His blessed light and warmth fail us not. 
The sun appears as a luminous disk. When seen 
at or near the horizon it seems to be larger than in the 
zenith. This is an illusion. Things far away by them¬ 
selves appear smaller than when there are objects in¬ 
tervening which serve as points of measurement for 
the eye. 
How large does the sun appear to you ? To some 
it looks like a good-sized dinner-plate, to others like a 
saucer, and to still others like a bicycle-wheel. In 
degrees the diameter of the disk measures ten and a 
half times the distance between the middle and end 
stars of Orion’s belt, but the real diameter is about 
ten times that of the earth. 
There are many things of interest to be said about 
the sun, but in this volume space can be given to only 
the most practical points in connection with such ob¬ 
servations as any one may easily make. 
First, we may observe the time and place of his 
rising and setting. On the first day of spring and of 
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