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Equations (5) ^nd (6) have been integrateO by the Nautical Almanac office for a 1 gram charge of 

 T.N.T. Between rigid walls 18 inches and 12 inches apart. It is found that b first rises to a positive 

 maximum then diminishes and changes sign and becomes numerically large. A positive value of b becoming 

 comparable with the radius of the Bubble would imply that it splits in half. The results can only be 

 qualitatively correct, Both Because for such small veluos of we cannot neglect the higher order 

 perturbing terms, and also because a no. 8 cap seems to correspond more closely to -a 0.6 gram charge than 

 to a 1 gram charge. some specimen results are as follows:- 



Table III. Distor tion of BuBBle d ue to rigid walls alone compared with that du e to gravity a lone. 

 1 gram of T.N.T. 3 feet Below surface. 



Experimental facts . Period of Bubble in open water 23 milliseconds. 



Between plates 18" apart period =22-23 milliseconds. Bubble does not divide. 



Between plates 12' apart buBBle divides after 21 milliseconds. 



Maximum radius of bubble 5. i" 



AS already stated, the discrepancies in period and maximum radius are due to assuming too targe a 

 value for the energy of the No. 8 caps. It will be seen that for the plates 12* apart, b becomes posit iy« 

 and comparable with a, corresponding to splitting of the Bubble, one half going to each plate, whereas for 

 the plates 18" apart, B eventually becomes negative and comparaBle with a, corresponding to a flattening 

 of the BuBBle along the plane midway Between the plates. In the actual experiment gravity acts in a 

 direction perpendicular to the line we have taken as the 5 axis, so that. By itself, it would tend to flatten 

 the BuBble along a horizontal plane perpendicular to the plates, and would thus tend to assist the splitting 

 effect due to the plates. By the use of tes'seral Instead of axial harmonics one could take account of the 

 effect of gravity and the rigid walls simultaneously, But this reflnenffint seems hardly worth while, as we 

 have already shown that the theory of this phenomena is in qualitative agreement with experiment. 



Conclusions . 



The comparison of phenomena on the detonator scale with experiment reveals very much the same sort 

 of situation as exists for large charges. The simple theory, assuming that the bubble remains spherical 



throughout ... 



