THE STORY-BOOK OF SCIENCE 



"Objects seem to us small in proportion to their 

 distance from us, until finally they become invisible. 

 A high mountain seen from afar seems only a mod- 

 erate-sized hill; the cross that surmounts a steeple, 

 seen from below, looks very small despite its very 

 large dimensions. It is the same with the sun: it 

 looks so small only because it is very far off ; and as 

 the distance is prodigious, its size must be excessive ; 

 if not, instead of looking to us like a dazzling grind- 

 stone, it would cease to be visible to us. 



"You found the terrestrial globe enormous; and, 

 despite my comparisons, your imagination, I am 

 sure, has not been able to picture things properly. 

 How will it be with the sun, which is one million four 

 hundred thousand times as large as the earth! If 

 we suppose the sun hollow like a spherical box, to 

 fill it would take one million four hundred thousand 

 balls the size of the earth. 



' l Let us try another comparison. To fill the meas- 

 ure of capacity called the liter, it takes about 10,000 

 grains of wheat. It would take, then, 100,000 to fill 

 10 liters or one decaliter, and 1,400,000 to fill 14 

 decaliters. Well, suppose in one pile 14 decaliters 

 of wheat, and beside it one solitary grain of wheat. 

 For the respective sizes, this isolated grain repre- 

 sents the earth; the pile of 14 decaliters represents 

 the sun. ' ' 



1 ' How wrong we were ! ' ' Claire exclaimed. ' ' This 

 little shining disc, to which, for fear of exaggera- 

 tion, we should have hesitated to assign the dimen- 

 sions of a millwheel, is a globe so big that in com- 



