Correspondence. Accidents in Mines. Part Ii.

Abstract

Ah. Cochmne. ments with which he had been connected in 1875 and 1876, when the first steps were taken in this country, after certain indications given by Mr. Vital in the 'L Annales des Mines," that small coal-dust, per se, was explosive without the possibility of admixture with carburetted hydrogen. Probably everyone would be impressed by the perusal of the Paper with the idea that a slight admixture of firedamp was necessary for an explosion. H e did not know what would be called an explosion, but if, as in an experiment which he condncted with Professor Marreco, in January 1876, in the laboratories of the Physical Science College a t Newcastle-on-Tyne, a detonation and the projecting of two small cast-iron weights from the top of a model drift, one going uncomfortably near his head, and the other across the experiment room, were to be called an explosion, it certainly took place, with the use of coal-dust alone, there being no possibility of having gas anywhere near where they were operating. A Davy lamp gauze formed the roof of the model drift, on which the dust coal was placed, a small Guibal fan supplied the air-curret, and by rapping the side of the model drift the coal-dust fell, and a small pistol was fired into the drift. The result was an explosion, which ripped up the model and destroyed the Guibal ventilator employed t o maintain the air-current. That showed that there was no necessity for the presence of even the smallest percentage of gas, which had been so much dwelt upon, and which the Author concluded was necessary.