MEASUREMENT OF PRESSURES 209 



shot, adjustments and tests while the event occurs being almost invari- 

 ably difficult and often impossible. These difficulties are particularly 

 great for large charge work, in which a single shot represents a large 



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:C 



1^ 



MOMENTUM GAUGE RIG 



Fig. 5.26 An arrangement of gear for large scale explosion tests. 



investment in time and money, and seemingly excessive precautions to 

 insure reliable functioning of equipment usually justify themselves in 

 the end. 



