MRS. B.
And this is actually the case, for the top of the lamp is very apt to become red-hot. But, fortunately, inflammable gaseous mixtures cannot be exploded by red-hot wire, the intervention of actual flame being required for that purpose; so that the wire does not set fire to the explosive gas around it.
EMILY.
I can understand that; but if the wire be red-hot, how can it cool the flame within, and prevent its passing through the gauze?
MRS. B.
The gauze, though red-hot, is not so hot as the flame by which it has been heated; and as metallic wire is a good conductor, the heat does not much accumulate in it, as it passes off quickly to the other parts of the lamp, as well as to any contiguous bodies.
CAROLINE.
This is indeed a most interesting discovery, and one which shows at once the immense utility with which science may be practically applied to some of the most important purposes.
[*] This ingenious explanation was first suggested by Dr. Delarive.—See Journals of the Royal Institution, vol. i. p. 259.
[*] Or rather, hydro-carbonat, a gas composed of hydrogen and carbon, which will be noticed under the head Carbon.