46 Common Science 



mountains tumble down, fall to pieces, and sink into an 

 inconceivably fine dust. Nothing stands up in the world 

 not a tree, not an animal, not an island. With a 

 wild rush the oceans flood in over the dust that has 

 been nations and continents, and then this dust 

 turns to a fine muddy ooze in the bottom of a world- 

 wide sea. 



But it is an ocean utterly different from what we have 

 in the real world. There are no waves. Neither are 

 there any reflections of clouds in its surface, first 

 because the clouds would fly to pieces and turn to 

 invisible vapor, and second, because the ocean has no 

 surface it simply melts away into the air and no one 

 can tell where the water stops and where the air 

 begins. 



Then the earth grows larger and larger. The ocean 

 turns to a heavy, dense, transparent steam. The fine 

 mud that used to be rocks and mountains and living 

 things turns to a heavy, dense gas. 



Our once beautiful, solid, warm, living earth now 

 whirls on through space, a swollen, gaseous globe, 

 utterly dead. 



And the only thing that prevents all this from actually 

 happening right now is that there is a force called 

 cohesion that holds things together. It is the pull 

 which one particle of anything has on another particle 

 of the same material. The paper in this book, the 

 chair on which you are sitting, and you yourself are all 

 made of a vast number of unthinkably small particles 

 called molecules, each of which is pulling on its neighbor 



