Prof. Dwbereiner's recent Discovery , to Eudiometry . 818 
Sir H. Davy has satisfactorily proved, that the combustion of 
an explosive mixture ceases when the heat produced in the pro- 
cess is very rapidly removed ; and he has rendered it probable, 
that the coexistence of carbonic acid and other gases tends to 
extinguish burning bodies, by the velocity with which they car- 
ry off the caloric disengaged during the combustion. It is, 
however, by no means clear, that this is the only efficient prin- 
ciple, and an investigation of the relative power of different 
gases in preventing the inflammation of combustible substances, 
would be very interesting, and might throw considerable light 
upon this subject. From the close analogy between the effects 
of Flame and of Electricity, on explosive gaseous mixtures, it 
must be supposed that the same causes which modify the action 
of the one, would likewise exert some influence on the other. 
Now, reasoning from the best data we at present possess, it is 
impossible to maintain, that the effect of different gases in pre- 
venting the action of electricity arises only from their cooling 
agencies. Hydrogen and nitrous oxide, whose capacities for 
heat, according to De Laroche and Berard, are widely diffe- 
rent, have an equal power of counteracting the effect of electri- 
city. The capacities of olefiant gas and nitrous oxide bear no 
proportion to their relative powers of preventing explosion ; and, 
by reference to the preceding Table, other examples of a simi- 
lar nature will readily present themselves. It is therefore pro- 
bable, that some other than the usually acknowledged principle 
is applicable in the instance of combustion, as well as in that of 
electricity. This view receives additional support from the foL 
lowing experiments. 
The presence of oxygen, hydrogen, and atmospheric air, has 
so little power in preventing the action of platinum, that I have 
not been able to ascertain the exact limits at which it ceases in 
such mixtures. 
Very different is the effect of some other elastic fluids. In 
mixtures composed of 
Exp. Mixt. Effects of a Platinuvi hall , 
1 vol. of Carbonic Oxide, and 3 vol. a Platinum ball had no effect when 
cold, and hardly any when warm. 
- " “ - - 5 Very sluggish action when cold, but 
good action when warm. 
