244 ELEMENTS OF GENERAL SCIENCE 



by means of our intellects that we may know something of 

 this vast universe. One astronomer 1 has said: 



If the human mind sometimes seems to have wings, by the aid 

 of which it conquers stellar space ; if man by his intellectual 

 courage lifts himself to sublime heights it must also be borne 

 in mind that he is really a very small atom in nature's colossal 

 work. We feel our infinite littleness when contemplating the 

 wonder of a starry night, above all ; for we know that these are not 

 mere points of light that we see twinkling in the vast dome of the 

 sky they are suns, huge incandescent globes, gigantic foci of 

 light, centers of systems of worlds ! We know, too, that those 

 distant stars resemble the star which illuminates our own world, 

 and that in the vastness of space our sun is but a star. 



249. Phases of the moon. Every thoughtful person has 

 looked at the moon in wonder and has noted its apparent 

 change of shape during the month. Each month when it is 

 a " new moon " it seems to be a thin crescent, with the tips 

 turned toward the east (fig. 123). A few days later it has the 

 form of a semicircle, and in another week it appears to be per- 

 fectly round. Then it gradually changes in the reverse order 

 to the semicircle and to the thin crescent, with the tips now 

 turned toward the west. Primitive peoples noted the regu- 

 larity of these changes and measured their time by them, the 

 American Indians saying that in so many moons this or that 

 religious festival or other occurrence would take place. 



The moon is not a light-giving body except in the sense 

 that it reflects light which shines upon it from the sun. It 

 moves around the earth and is carried with the earth around 

 the sun. Its changing positions -relative to the earth and sun 

 cause its changing appearances, which we call its phases. 



250. Amount of light from the moon. It sometimes seems 

 that the amount of light received from the moon is very 

 great and that it may be a considerable fraction of that 



1 Flammarion, Camille, Astronomy, pp. 128, 129. 



