direct wave is negligable for most of the shots. (The ray 
paths for these various arrivals are shown in Figure 14.) 
/ 
B SEA LEVEL rn) 
OCEAN GOTTOM 
Fige 13 Ray path for Ry Fige 14 Ray paths for D, Rj, and G 
Figures 15 - 17 are graphs of cos ® verus direct 
wave travel time, i. e-, range,for the first, second, and 
third reflections.e The factor that is needed to multiply 
the sum of the depths of the shot and hydrophone can be read 
directly off this graph for the particular range involved. 
Figure 18 is a graph of cos O versus the ratio cy, / Bye From 
this graph the same factor can be read off forthe refraction 
