PROFESSOR H. B. DIXON ON THE RATE OF EXPLOSION IN GASES. 139 
Berthelot’s formula, but falls far below the velocity of sound “S.” On the other 
hand, the rate of explosion of ammonia and nitrous oxide is close to the calculated 
sound-wave and is far above “ 6.” 
Table XXXIII. 
Explosive gases. 
Heat 
developed. 
Expansion. 
Specific teat 
of products. 
Mean density. 
1 . 
4 NH 3 + 3 O 2 
305,200 
7 : 8 
4-8x11 
•761 
2. 
2NH3-f3N20 
193,800 
5 : 7 
4-8 X 8-5 
•987 
( 1 -) 
Mixture. 
4 NH 3 + 302 . 
Berthelot’s 0 . . . 
2300 
Rate of explosion . 
2390 
V 
2665 
( 2 .) 
Mixture. 
2NH3-f3N20. 
Berthelot’s 0 . . . 
1953 
Rate of explosion . 
2200 
y 
2223 
Mixtures of oxygen with the hydrocarbons ethylene and acetylene will exj^lode 
when largely diluted with nitrogen. For instance, the explosion-wave is projiagated 
in a mixture of one volume of ethylene with two of oxygen and eight of nitrogen. 
The temperature reached in the explosion is comparable with that produced when 
three volumes of electrolytic gas are fired with five volumes of nitrogen . It is found 
both with ethylene and acetylene that the rate of explosion exactly aa’rees with the 
calculated velocity of the sound-wave when the mixtures are largely diluted with 
nitrogen, but not when the gases are exploded without dilution :— 
rji Q 
