flat from 400 cps to 15 kc. The system was capable of meas- 

 uring over-all sound pressures as low as 0.1 dyne per square 

 centimeter, corresponding in the wide band covered to an 

 average spectrum level of approximately 0.001 dyne per 

 square centimeter. This level was found to be inadequate 

 for the extremely low noise levels encountered. 



For many of the measurements, it was impractical to get 

 far enough away from the ships to record water noises. At 

 other locations, surf noises predominated. In a few locations, 

 however, measurements were possible where ships and surf 

 noises did not interfere and, in most of these cases, charac- 

 teristic sounds could be recognized and described. Near the 

 ice pack the noises were too low to be read on the meter, but 

 they could be heard in the earphones. These noises were in 

 the medium or low audio-frequency range and were com- 

 pared to the sounds of rushing water with an occasional splash, 

 as if from large chunks of ice sinking beneath the surface. 

 Although exact levels could not be established, it can be con- 

 cluded that a very low noise level occurs in this area, with 

 no evidence of noises of a biological origin. 



