RUNNING WATERS 371 



from a reservoir. In coming from the sea, before 

 becoming what it is, the brook has first passed 

 through the air as clouds. " 



"As clouds 1" 



"As clouds, my little friend. Let us recall some- 

 thing I told you a while ago. 



"The heat of the sun causes water to evaporate; 

 it reduces it to something invisible, to vapor that is 

 dissipated in the air. Seas present a surface three 

 times that of the dry land. Over these immensi- 

 ties there is constantly taking place an enormous 

 evaporation, raising into the air a part of the waters 

 of the sea. The vapor thus formed becomes clouds ; 

 the clouds are borne in all directions, letting down 

 snow and rain; this rain and melted snow penetrate 

 tin- ground, filter down and give birth to springs, 

 which gradually, by their union, become brooks, 

 streams, and rivers." 



"I see why the water of brooks is not salt," said 

 Jules, "although it comes from the sea. When you 

 put salt water in a plate in the sun, only the water 

 goes away; the salt remains. The vapor that rises 

 from the sea is not salt, because the salt does not go 

 with it when it forms. So streams fed by snow and 

 rain that fall from the clouds cannot be salt. ' ' 



"What you have just told us is very remarkable, 

 !e," observed ( laire, "All water-courses, riv- 

 ers, streams, torrents, brooks, come from and return 

 to the sea." 



"They come from the sea, an inexhaustible reser- 



that covers with its waters a surface three times 



larger than that of all the continents joined to- 



