AT a meeting of the Physical and Chemical Section of the Bristol Naturalist Society, on January 26, a paper was read, by Mr. Donald M. D. Stuart, upon “The Chemistry of Colliery Explosions due to Gases derived from Coal-dust,” in which the researches of Faraday, Verpilleux, Vital, Marreco, Mallard, Le Chatelier, arid others were given, and attention was drawn to the points they emphasised. Faraday observed in his report upon the Haswell Colliery explosion: “There is every reason to believe that much coal-gas was made from the coal-dust in the very air itself, by the flame of the fire-damp;… and that much of the carbon in this dust remained unburnt only for want of oxygen.” M. Vital concluded that—“Very fine coal-dust rich in inflammable constituents, will take fire when raised by an explosion, and that portions are successfully decomposed, yielding explosive mixtures with air, whereby the fire is carried along.” Marreco remarked—“The coal-dust is in part submitted to destructive distillation”; and Mallard and Le Chatelier found that gaseous matters were evolved from the coal-dust by the action of the fire-damp explosion. Mr. Stuart observed. These physicists and chemists found that the coal-dust did undergo dry distillation while in atmospheric suspension in a mine passage, after the originating explosion; and the educts added to the explosive effects. He had carefully observed the effects of explosions not only at the point of origin, but throughout the field of the disturbances, and found Faraday's hypothesis of the dry distillation of coal-dust essential to account for the phenomena observed through thousands of yards of mine passages. He observed that the disruptive effects of an explosion of methane and air were necessarily limited to the immediate vicinity of the explosive mixture; but the disruptions beyond and to remote distances required an explosive agent coextensive in distribution, and this agent was coal-dust.