THE SEQUENCE OF EVENTS 

 or more such oscillations having been detected in favorable cases. 



The 



number observable is limited by its loss of energy by radiation or tur- 

 bulence, as described in the next section, and by the disturbing effects 

 of gravity and any intervening boundary surfaces. It is perfectly evi- 

 dent that the gaseous products must, because of their buoyancy when 

 in equilibrium with the surrounding pressure, eventually rise to the sur- 



25 



I 



UJ 



o 



50 



75 



Fig. 1.4 



0.2 



0.4 

 TIME (sec) 



06 



08 



Displacements of the gas sphere from a 300 pound TNT charge 

 fired 50 feet below the surface. 



face. It is less evident that the gas sphere will in the course of its 

 oscillation experience a net repulsive force away from a free surface and 

 will be attracted toward a rigid boundary. The motion of the gas 

 sphere is thus affected by its buoyancy and by the proximity of the sur- 

 face of the water and the sea bed or other boundary surfaces. These 

 complications make detailed calculations of bubble behavior difficult in 

 spite of the fact that during most of its motion the changes in density of 

 the surrounding water are negligible and the motion may be described 

 as incompressive flow. 



