390 



MR. J. E. PETAVEL ON THE PRESSURE OF EXPLOSIONS. 



Generally speaking, the results obtained confirm the remarkable properties ot 

 cordite with regard to its high power and to the regularity of the effects produced. 

 It would doubtless be very desirable to extend the research to higher pressures and 

 carry out, on similar lines, a comparative study of other explosives. Treated, however, 

 in this general way the subject is too vast to be dealt with single-handed, and the 

 writer can but express a hope that others more competent and better equipped will be 

 found willing to take up the work. 



Before closing I desire to thank Professor ARTHUR SCHUSTER for placing at my 

 disposal the ample resources of his laboratory. 



The cost of the apparatus has to a large extent been defrayed by funds awarded by 

 the Government Grant Committee of the Royal Society, while for the cordite I am 

 indebted to the courtesy of the War Office authorities. 



APPENDIX. 



In the following tables numerical results obtained from the measurements of the 

 principal photographic records will be found. 



Where wave action is set up, the pressure given is the mean value of the 

 instantaneous pressure at the time indicated. 



TABLE I. (Record No. F 55.) 



Spherical explosion vessel ; charge uniformly distributed ; gravimetric density - 0496 ; diameter of cord 



0-475 inch (12-07 millims.). 



Maximum pressure 404 atmospheres (2 '65 tons per square inch); time required to reach 

 the maximum pressure 0'120 second. 



