MULTIPLE REFLECTED WAVES 



89 



These formulas do not apply to the vicinity of the points of origin of head 

 waves. 



Fig. 8 shows graphs representing the dependence of ^on distance from the 

 source for various waves, and Figs. 6 and 9 show the corresponding theoretical 



Fig, 10a. Graphs showing intensity of double reflections as function of angle 

 of incidence with different wave resistances of a thin reflecting layer, a — predominant 

 frequency of radiated vibrations 60 c/s, b — predominant frequency of radiated 



vibrations 30 c/s. 



