THE KEASON WHY. 173 



* Behold, the nations are as a drop of a bucket, and are counted as the small 



dust of the balance : behold, he taketh up the isles as a 



very little thing." ISAIAH XL. 



4. The attraction of electricity. 



5. And capillary attraction. 



774. Why do all bodies heavier than the air fall to ths 

 earth ? 



Because they are influenced by the attraction of gravitation, by 

 which all bodies are drawn towards the centre of the earth. 



775. Why do bodies lighter than the air ascend? 

 Because the air, being a denser body, obeys the law of attraction, 



and in doing so displaces lighter bodies that interfere with its 

 gravitation. 



776. Why do fragments of tea, and bubbles floating 

 upon the surface of tea, draw towards each other, and attach 

 themselves to the sides of the cup. 



Because they are influenced by the attraction of cohesion. 

 Cohesion. The act of sticking together. 



777. Why will a drop of water upon the blade of a knife 

 leave a dark spot ? 



Because the iron of the Tcnife attracts the oxygen of the water, by 

 chemical affinity ; and the two substances form a thin coating of 

 oxide of iron. 



Affinity, Attraction between dissimilar particles through which they form 

 new compounds. 



778. Why do clouds sometimes move towards each other 

 from opposite directions ? and 



779. Why do light particles of matter attach themselves 

 to sealing wax, excited by friction ? 



Because they are moved by the attraction of electricity . 



780. Why will a towel, the corner of which is dipped ii* 

 water, become wet far above the water ? 



Because the water is conveyed up through the towel, by 

 capillary attraction. The atoms of the water are attracted by the 

 threads of the towel, and drawn up into the small spaces between 

 the threads. 



Capillary. Resembling a hair, small in diameter. 



