thomas] THE MOON 369 



cold place, then the water in the air condenses again and makes 

 clouds. 



Fog and haze are clouds. The haze is where the moist air is 

 just a tiny bit cooled, and therefore the water is slightly condensed, 

 this often happens when the sun is going down. If the air becomes 

 still thicker, that is, has more water condensed in it, and we cannot 

 see things around us, we say there is a fog. Fogs are more apt 

 to occur where there is a good deal of dust floating in the air, 

 since the mixture will condense into water around these tiny bits 

 of dust. When the temperature of the atmosphere falls to a cer- 

 tain degree of coldness the air is unable to hold the moisture and 

 lets it go as rain. But if it gets still colder, and the air is full of 

 water it condenses into crystals and makes snow instead of rain. 



Thus we see that the rays of the sun, before they fall on the earth 

 and warm it, must warm all this blanket of air that is between us 

 and it, and the air blanket because of the heat absorbs water and 

 so, our weather will van-. 



But on the moon, where there is no water to be taken up by 

 the air and no air to take it up anyway the clouds cannot be formed 

 nor changed from rain clouds to snow clouds, so the weather on 

 the moon does not vary. 



With no water inside the ground to freeze, and push the particles 

 of rock apart, as the water swells in freezing, the rocks would not 

 break up into little particles as they do on the earth, and therefore 

 the rocks on the moon would probably stay rocks forever, instead 

 of breaking up into soil, as they do on the earth, unless the meteors 

 batter them into pieces. 



QUESTIONS ON THE PHYSICAL GEOGRAPHY OF THE MOON 



Do you think there can be any life on the moon? Why not? 



What do you think the color of the moon's sky is ? Why ? 



How does our sky look before sunrise, and at sunset ? Does the 

 moon's sky look the same? 



If you were on the moon, how do you think the sun would look? 

 How would the stars look? Would they look as they do from 

 the earth? Why? What can you tell about the shadows on the 

 moon ? 



If we had no air on the earth would you be able to guess whether 

 the mountains were a long way off or close at hand' Why' 



