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destroyed. The temperature of metal evenwhen white hot, is far below that of flame;and hence red hot gauze, in sufficient quan-tity, and of the proper degree of fineness,will abstract sufficient heat from the flameof carburetted hydrogen or fire damp, toextinguish it.

Combinations of gases may be occasionedby a heat not sufficient to raise their tem-perature into flame, but they still produceheat during their combination, as is evidentfrom what has been stated page 17, andwhen in a mixture containing air and com-bustible gases, the cooling agencies are toogreat to permit the appearance of flame ortheir continued combination ; still this com-bination may be kept up by the ignition ofplatinum, so that with a certain quantity ofplatinum in a cage of wire gauze, the firedamp may be entirely consumed withoutflame, yielding only a beautiful light by theignition of solid matter.