138 PROFESSOR H. B. DIXON ON THE RATE OF EXPLOSION IN GASES. 
similar divergences which admit of the same explanation. It is to be noted in the 
case of hydrogen and nitrous oxide that no alteration of volume occurs in the chemical 
change ; no correction in temperature need, therefore, be made in calculating the 
sound-wave, and the question of the density of the molecules concerned does not 
arise. 
Table XXXI.—The Rate of Explosion of Electrolytic Gas with excess of 
Nitrogen compared with Calculated Velocities. 
Mixture. 
H. + O 
Ho-l-O + N j H 0 + O + N 3 
H 2 + O + N 5 
Beethelot’s 0 . . . 
2900 
2321 
1814 
1558 
Rate of explosion . 
2821 
2426 
2055 
1822 
2 . 
3416 
2731 
2122 
1813 
Table XXXII.—The Rate of Explosion of Hydrogen and Nitrous Oxide, with 
excess of Hydrogen, and of Nitrogen, compared with Calculated Velocities. 
Mixture. 
H^ + NoO 
Hg + N^O 
H.-t-NgO 
H2 + N0O 
H3 + N2O + N2 
H3+N2O + N3 
Beethelot’s 0 . . . 
2400 
2396 
2374 
2319 
1912 
1782 
Rate of explosion . 
2732 
2705 
2.545 
2305 
1991 
1880 
v 
2776 
2781 
2765 
2706 
2227 
2067 
When electrolytic gas is diluted with excess of nitrogen, the observed rate of 
explosion closely agrees with the calculated sound-wave. With hj^drogen and nitrous 
oxide the temperature cannot he diminished to the same extent by dilution. When 
three volumes of hydrogen, or two volumes of nitrogen, are added to the mixture 
consisting of one volume of hydrogen and one of nitrous oxide, the explosion-wave is 
not propagated with regularity; consequently the temperature cannot be brought 
down by dilution below the dissociation-point of steam. As the mixture is diluted 
the rate of explosion approaches but agreement is not reached at the limits of 
dilution at which the explosion-wave will still travel. 
The rates of explosion of mixtures of ammonia with oxygen and with nitrous oxide 
were also determined. The gases were mixed in an iron holder standing over mercury. 
The rate of explosion of ammonia and oxygen is faster than the velocity calculated by 
