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wire burns, and the explosion could neverbe communicated. The flame of the fire-damp flickered and roared in the lamps, butdid not escape from its prison.

There is no reason ever to expect a streamof gas of this kind in a mine; but, if it shouldoccur, the mode of reaching and examiningit, with most perfect security, is shown ;and the lamp offers a resource, which cannever exist in a steel-mill, the sparks ofwhich would undoubtedly inflame a currentof this kind.

If a workman having only a commonsingle lamp, finds the temperature of thewire increasing rapidly in an explosive mix-ture near a blower, he can easily diminishthe heat by turning his back upon thecurrent, and keeping it from playing uponthe lamp, by means of his clothes or hisbody; or by bringing the lamp nearer theorifice, from which the fire-damp issues, hemay extinguish it; and there never can beany occasion for him to place his lamp inthe exact point where two currents one offresh air and one of fire-damp meet eachother.

When the fire-damp is inflamed in the