Provide about a foot square of brass or iron wire gauze, of the
fineness of thirty meshes to the square inch: lower the gauze upon the
flame of a wax candle, which will not rise through the meshes, but in
its place will be the inflammable smoke of the flame; apply to this a
piece of lighted paper, and it will be kindled, and the candle will
burn with flame above and beneath the gauze. In this case, the gauze
so cools the flame, as to extinguish it; and upon this principle is
constructed the Davy Safety Lamp, in which the light is surrounded with
wire-gauze.
To vary this experiment, place a chip of camphor in the centre of a
piece of wire-gauze about a foot square, and hold it over the flame of
a candle or lamp; when the vapour of the camphor will burn brightly
upon the lower surface of the gauze, but cannot rise through it in
consequence of its cooling power. Thus, the camphor lies upon the gauze
in an uninflamed state, though it is sufficiently heated to yield
inflammable vapour to feed a flame beneath.