The Rate of Explosions in Gases. 



145 



Here, as in the case of electrolytic gas, the rate for the 

 pure mixture is in close agreement with the calculated 

 velocity. Taken by itself, this experiment (not tried by 

 Berthelot) would have offered strong confirmation of the 

 correctness of the theory. But as successive additions of 

 nitrogen are made to the mixture, the calculated velocities 

 fall below the observed rates, until with a large excess of 

 nitrogen, the calculated rate is 16 per cent too low. 



The gradual divergence between the observed and the 

 calculated rates of explosion for different gaseous mixtures, 

 as successive quantities of nitrogen were added to the pure 

 explosive gas, led me to try the effect of diluting electro- 

 lytic gas with hydrogen. According to Berthelot's formula 

 a slight increase in the rate should occur; actually a very 

 marked increase in the rate was observed. 



Table XVII. , 



Rate of Explosion of Electrolytic Gas with excess of 

 Hydrogen added. 



§7. If it is true, as Berthelot insists, that the formula 

 gives a maximum velocity, which may be reached, but not 

 surpassed, by the explosion wave, it is obvious that either 

 the experiments or the formula is at fault. 



Since the amount and regularity of the divergence 

 between the found and calculated rates precluded the idea 

 of experimental error being its sole cause, I was driven to 

 conclude either that the hypothesis was incorrect, or that 



