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mixtures of the gas as the flame of the taper.Well burned charcoal, ignited to thestrongest red heat, did not explode any mix-ture of air and of the fire-damp; and a firemade of well burned charcoal, i. e. charcoalthat burned without flame, was blown up towhiteness by an explosive mixture contain-ing the fire-damp, without producing its in-flammation. An iron rod at the highestdegree of red heat, and at the common de-gree of white heat, did not inflame explosivemixtures of the fire-damp; but, when inbrilliant combustion, it produced the effect.

The flame of gaseous oxide of carbon aswell as of olefiant gas exploded the mix-tures of the fire-damp.

In respect of combustibility, then, thefire-damp differs most materially from theother common inflammable gases. Olefiantgas, which I have found explodes mixed inthe same proportion with air, is fired byboth charcoal and iron heated to redness.Gaseous oxide of carbon, which explodeswhen mixed with 2 parts of air, is like-wise inflammable by red hot iron and char-coal. And hydrogene, which explodeswhen mixed with three-sevenths of its