1444 
2 se 
ie = aca —> - a 
crit 2 i, % ordé aK Z (16) 
Applying (9a) and (9b) it will be obtained 
s ral 
Pentolite Peover t1008id (16a) 
¥ -¢ 
TNT Forit 7 0-6 4 (16b) 
These formulas show that there exists a critical distance even 
for large depths, that is, for small pressures at the surface. 
If the charge weight is kept constant and the depth d is de- 
creased, this critical distance decreases much faster because 
Yorit d* , Therefore we quickly approach a range where the 
approximations are no longer correct. 
For this reason it is necessary to control the range where 
(16) may be used. This is simply obtained in checking the assump- 
tions. Formula (16) is correct as long as T = alr 7p) < 500 at. 
If the initial peak pressure at the critical distance is 
larger, a general consideration is necessary. This general cal- 
culation for ee es function of the depth d is not difficult 
if the pressure-distance relations (Fig. 2) and the relations 
between are and the pressure (Fig. 3) are used. The relation 
between @ ares and Boete is given by sin @ = Or ae . 
All calculations will now be carried out in expressing all dis- 
tances in charge radii. The way of obtaining the derived relation 
between Tropy4 and d is as follows: Starting with a certain 
16 
