108

COAL MINES OF

every thing before them. It is evident thatventilation, even in its improved state, hasafforded no relief whatever; and here the ap-paratus which, in the first instance, I havethe honour to lay before the Royal Society,will be found to afford a good light unaccom-panied by danger.*

ee It very frequently happens that accumu-lations of carbureted hydrogen gas, mixed withatmospheric air, take place in the wastes or oldworkings of the coal mines ; and though muchprecaution is used for keeping this inflammableair confined to its proper places, by means ofpartitions and folding-doors, nevertheless, whenby carelessness or accident the air comes intocontact with any ignited substance, an explo-sion generally takes place.

“ These explosions happen when the pit-men are occupied in heaving out the coal atthe workings , should they chance to open acavern of unmixed carbureted hydrogen gas.This gas, for the most part being pent up in acondensed state, rushes from a chasm, andforming what is locally denominated a blower,it suddenly mixes with the atmospheric air ofthe mine, and, surrounding the lights of the

* See Thomson’s Annals, and Tilloch’s Phil. Mag. forJune 1813.