386 REFRACTION. 



can be seen by the spectator A ; the rest of the ship 

 is hidden by the swell of the curve D E. 



Q. What is meant by REFRACTION ? 

 A. The lending of a ray of light, 

 as it passes from one medium to another. 



Q. How is a ray of light BENT, as it passes 

 from one medium to another ? 



A. When a ray of light passes into a 

 denser medium, it is bent towards the 

 perpendicular. When it passes into a 

 rarer medium, it is bent from the per- 

 pendicular. 



Suppose D E to be a perpendicular line. 



If AB (a ray of light,) enters the water, it will be bent 

 towards the perpendicular to C. 



If (on the other hand) CB (a ray of light) emerges 

 Jrom the water, it would be bent away from the per- 

 pendicular towards A. 



