The Mining Engineer Volume 27

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 Excerpt: ...has immediately set the igniter at work without even waiting for the gauze tocool down. As the writer remarked at the outset, the Frameries experiments have not yet been brought to an end. Nevertheless, those that have been carried out in regard to lamps have reached a sufficiently-advanced stage to permit of the following brief synopsis of some of the conclusions to which they lead: --(1) The use of benzine does not diminish in any notabledegree the safety of the lamps in which it is burnt. (2) Several shielded or bonneted lamps, especially theMarsaut lamp and the Wolf benzine-lamp are shewn to be considerably safer than the Mueseler lamp. The last-named, which shews a perfect capacity of resistance in horizontal currents, rapidly breaks down in upward currents. (3) The internal igniter, if made of phosphorized paste and worked by friction only, may be often used without danger in. the midst of atmospheres charged to extreme with fire-damp. This does not, however, apply to every type of lamp, especially not to the Mueseler, where the working of the igniter causes theflame to pass into the upper gauze. II.--Explosives. In Belgium, the use of explosives in mines is regulated by the Royal Decree of December 13th, 1895. The provisions of this decree are very stringent in regard to the use of explosives generally. Thus, for instance, the use of any explosive whatsoever is prohibited: --(1) For breaking down masses of coal; (2) For breaking down masses of rock in workings ventilated by a downward current; (3) In places where one may expect to come upon ancient workings; (4) For driving roads: in the upper return-airway, in all galleries save the intake-airway, or in all working places, according as they belong to mines of class 2a, of class IIi or of class 3; (5)..