hingeens square law" is easily seaer as a aamanemance AG ‘ 
ion Bde conservation. — On the other hand, according to } 
ideal sound channel the only intensity loss is due to attenuation, 
eee Tinea ERE ERSe oe the HES EEIOE travell pos by the sound 
ieee distance Bound ranging system is based on the faet that 
mating at a depth beneath the main thermocline (about 4000 feet 
Atlantic Ocean) are effectively channeled by natural con- 
ae is so effective that the Se een of one pound 
ne t ic in arval between an glasien § in the sound channel ann the 
val rc. the nd at a distant monitoring station is proportional to the 
vai of the sound at three separate stations can be 
1 Bie This report describes the method for installing and. 
she equ pment which has been developed in experimental form for 
and tin g the arrival of such signals, 
the ee ee in the ocean decreases rather steadily down to 
Oey 4000 feet in the North Atlantic) and below this depth 
EEE pressure, on the other hand, necueel sy, 
da. Thus, an explosion can be located by geometrical methods 
