Radiant Heat and Light 137 



the chair is by the direction from which the light is 

 coming when it reaches your eye. But if the light is 



^""" FIG. 65. In passing through the prism 

 ^~"" the light is bent so that an object at b 



^~~~ appears to be at c. 



^^^ 



f~**** bent on its way, so that it 



i c comes to your eye as it ordi- 



narily comes from an object 



off to one side, naturally you think the thing you are 

 looking at is off to one side. Maybe the diagram (Fig. 

 65) will make this clearer. 



Here in a is an object the same height as the eye. 

 The light comes straight to the eye, and one knows that 

 the object is level with the eye. In b the object is in 

 the same position as in a, but the prism bends the light 

 so that it strikes the eye with an upward slant. So the 

 person thinks the object is below the eye at c. 



Here is another experiment with bending light : 



Experiment 45. Fill a china cup with water. Put a 

 pencil in it, letting the pencil rest at a slant from left to 

 right. Lower your head until it is almost level with the 

 surface of the water. How does the pencil look? 



