COAL MINES OF

JQS

acid which it would create, it would only betransferring the danger from one source to ano-ther equally destructive. The effect of the gasupon the senses and feeling is certainly nota new discovery, as I found all miners withwhom I conversed sufficiently acquainted withevery information of this sort.

That no precaution is required in construct-ing lanterns of strong materials to withstandthe effect of explosions in the chamber of thelamp, I am much inclined to dispute. A lan-,tern capable of receiving one quart of inflam-mable air must be made very strong to bearthe expansion, particularly if the venting- aper-tures are confined to a small space. WhenMr. Brandling’s lamp was experimented uponat the Literary and Philosophical Society atNewcastle, the effect was so great as to forcethe sides very considerably; and even wasthis not the case, it is giving rather too danger-ous a latitude, as the nature of the uses towhich lanterns must be applied in' a collieryrequire the greatest strength.

When at Sunderland, in the latter end ofMarch, I was informed of Sir H. Davy beingthen at Newcastle, and that his lamps werenot found sufficiently secure in their presentstate for application in a colliery.

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