REFRACTION. 



85 



2. The second factor will be mostly in favour of the 

 fish ; the fisherman gets most if not all the glint and re- 

 flection from the surface, though the glare of the sun 

 must handicap the fish to a great extent. 



3. The third factor is the background, which, however, 



DIAGRAM 9. 



A E D, a vertical section of the hollow cone in Diagram 8, cutting surface of 



water at A B. 



M N, any object on land, such as a man. 

 E b M, E B M, the lines along which the rays of light from the man M N will 



reach the fish. 



E b, E B, the direction in which the trout will see the man. 

 E d D, E d D, the lines showing the under surface of water, acting as a mirror 



to the trout of all objects under the water and outside the cone E A, E B. 



is almost invariably in favour of the trout. A dark back- 

 ground is of the greatest importance to the fisherman when 

 approaching a fish, and a sky line behind is always to be 

 avoided. If he, when fishing from the banks, has no near 

 background such as a wood, a hedge, a wall or tree, or 

 a cliff, etc., he should get near to the water level and as 



