G40 
MR. H. B. DIXON ON CONDITIONS OF CHEMICAL CHANGE 
velocity of explosion increased with, the quantity of steam added. When the mixture 
was saturated with steam at 60° C. the mean velocity was 317 metres per second. 
The following table gives the results of these experiments :— 
Table V. —Mean rate of explosion of carbonic oxide and oxygen through one 
metre with different quantities of aqueous vapour under atmospheric pressure. 
Exploded at 10° C. 
Exploded at 35° C. 
Exploded at 60° C. 
Rate in 
Rate in 
Rate in 
Hygrometric state. 
metres per 
Hygrometric state. 
metres per 
Hygrometric state. 
metres per 
second. 
second. 
second. 
Dried bj passing slowly 
36 
Dried by passing slowly 
44 
Dried by passing slowly 
53 
over fresh P 2 0 5 
over fresh P 2 0 5 
over P„0 5 used before 
Dried by passing slowly 
69 
over P 2 0 5 used before 
Dried by bubbling 
119 
Dried by bubbling 
102 
Dried by bubbling 
120 
through two bottles 
through two bottles 
through two bottles 
of H 2 S0 4 
of H,S0 4 
of H.,S0 4 
99 >? 
103 
Saturated at 6° . . 
129 
99 99 ... 
123 
Saturated at 8° . 
155 
Saturated at 8° . . 
158 
99 99 ... 
166 
Saturated at 10° . . 
175 
99 99 ... 
176 
Saturated at 12° . 
200 
Saturated at 12° . . . 
211 
Saturated at 35°. 
225 
Saturated at 35°. . . 
244 
99 99 ... 
226 
Saturated at 50° . . . 
289 
Saturated at 60° . . . 
317 
In each series of experiments the initial velocity of explosion of a mixture of 
carbonic oxide and oxygen is seen to increase with successive additions of steam. 
It is this initial velocity with which we have to deal in experiments with an ordinary' 
eudiometer. When a mixture composed of two volumes of carbonic oxide and one 
volume of oxygen, saturated wdth steam at 10°, is exploded under atmospheric 
pressure, the velocity of the explosion increases rapidly from the point of inflam¬ 
mation. In a tube of 13 millims. diameter and 55 metres long the rate of explosion 
is found to be constant after travelling 700 millims. along the tube ; the constant 
velocity of the “ explosive wave ” attained under these conditions being rather 
over 1500 metres per second. At the extremely high temperature accompanying 
the explosive wave, carbonic oxide is possibly decomposed ; after the explosion the 
