1437 
measured using the spark camera (Ref. 4) and the results of this 
investigation are also presented in Fig. 2. 
All results are in good agreement. The solid line drawn 
in Fig. 2 therefore is considered as a pretty reliable overall 
peak pressure-distance relation for the underwater shockwave of 
pentolite. 
The results for TNT, which were summarized in Ref. 6, 
Diagram 4, are replotted in Fig. 2 also. They show that the 
estimation of the high pressure part by A.B. Arons and D.R. 
Yennie agrees well with the obtained overall behavior of this 
relation for pentolite. This curve therefore will be used to 
derive results for TNT. 
The pressure range from 6000-20000 psi for pentolite is 
presented by formula (8) and a similar formula exists for TNT. 
However, because of the curvature of the pressure distance curve, 
the experimental results in the range of distances corresponding 
to the approximation formulas (2) and (4) can be described with 
adequate accuracy by the simple formulas 
oat hes ae 
Pentolite w= tt, & — == = sé 0 peo a (9a) 
= ; = 
~ — Ie a 135 
TNT We wae fnre ex e a, Re OOO RK pga) (9b) 
OF Vs r ~ 
