THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FIFTH SERIES.] 



MARCH 1886. 



XXVI. On the Theory of Explosions. By Richard 

 Threlfall, B.A., Assistant Demonstrator of Physics in the 

 Cavendish Laboratory, Cambridge* . 



IN his papers on the action of Detonators, Sir Frederick 

 Abel described some curious experiments, which he strove 

 to account for by a hypothesis of " synchronous vibrations/' 

 This hypothesis has been treated at considerable length by 

 Berthelot in his work Sur la Force des Matieres Explosives ; 

 and although much light, both experimental and theoretical, 

 has been thrown on the matter by Yieille and Berthelot, 

 the explanations offered by the latter do not seem altogether 

 satisfactory. I have therefore been led to imagine that 

 perhaps something of interest might be gathered from a study 

 of the behaviour of the products of explosion, especially as 

 regards the manner in which they escape from the centre at 

 which the explosion takes place. 



Much might possibly be learned from' a measurement of 

 the velocity of transmission of a shock to points at small 

 distances from the centre of explosion. This would be merely 

 a question of apparatus. Lord Rayleigh has suggested to me 

 the use of a sensitive flame and revolving mirror, which 

 would at all events give some idea of the sort of disturbance 

 experienced. But the best method of all seems to me to 

 begin by examining cases where the results of explosion can 

 be seen; and for this purpose I carried out the following 

 series of experiments during last autumn. 



* Communicated by the Author. 

 Phil Mag. S. 5. Vol. 21. No. 130. March 1886, N 



