LIST OF ILLUSTRATIONS 



Figtire 1. 



Figure 2. 



Figure 3. 



Figure 4, 



Figure 5» 

 Figure 6, 



Figure 7. 

 Figure 8. 



Figure 9. 



Figure 10. 



Figure 11. 

 Figure 12. 



Figure 13, 

 Figure 14, 



Figure 15. 



Page 

 Photograph of the ripple tank 5 



Schematic diagram of the ripple tank ... 7 



Refraction at a plane surface 13 



Photograph illustration Snell's Law. Waves 

 enter shallow water from deep water after 

 crossing abrupt transition rone 16 



Photograph showing refraction of light by 



a vertical glass cylinder 18 



Projection of the wave front on the plane 

 passing through the two caustics when the 

 plane wave is incident normal to the glass 

 cylinder 19 



Photograph showing refraction of waves by 



a submerged level disc at constant depth. . 20 



Projection of the wave front on the plane 

 passing through the two caustics, when 

 the plane water wave travels over a sub- 

 merged shoal of constant depth 21 



Refraction of sound waves in the 

 atmosphere due to a variation of 

 temperature 24 



Photograph showing refraction of water 



waves by a uniformly sloping beach .... 25 



Reflection by a rigid plane 27 



Photograph showing reflection of water 

 waves by a rigid breakwater. Angles of 

 incidence are approximately 60* and 45* . . 29 



Incident (x) , reflected (y) and refracted 



(z) rays at an air interface 32 



Photograph showing incident, refracted and 



reflected waves at the boundary of the 



step model 35 



Incident and totally reflected wave. The 

 observer (P) is in the second medium ... 37 



vil 



