LGU RE Nhe Sonagrams showing a@ combination of 
20 c/s Short Pulses and Long Pulses, Rhythmic 
Grunts (vertical striations between 50 and 150 e/s) 
and Motorboating (closely-spaced horizontal lines 
in the top Sonagram between 120 and 180 c/s). 
The frequency detail of the Motorboating sound 
rather than the time detail of its individual 
pulses is emphasized in this case because of the 
great (16 to 1) speedup of the tape playback, 
which resulted in an effective analyzing filter 
bandwidth of 3 c/s and great time compression. 
All three Sonagrams are from the shallow hydro- 
phone output and have the same zero time reference. 
26 
