Radiant Heat and Light 



FIG. 67. The bending of the light by the water in the glass causes the pencil to 

 look broken. 



of the pencil above the water comes straight to your 

 eye, of course ; so you see it just as it is. But the light 

 from the part of the pencil in the water is bent when it 

 conies out of the water into the air on its way to your 

 eye. This makes it come to your eye from a different 

 direction and makes the lower part of the pencil seem 

 to be in a place to one side of the place where it really 

 is. The pencil, therefore, looks broken. 



Whenever light passes first through something dense 

 like water or glass, and then through something rare 

 or thin like air, it is bent one way ; whenever it passes 

 from a rare medium into a dense one, it is bent the 

 other way. Light passing from a fish to your eye is 

 bent one way ; light passing from you to the fish's eye 

 is bent the other way, but the main point is that it is 



