DURHAM AND NORTHUMBERLAND. §5

melancholy beacon against trusting too muchto visionary securities.

The means of ventilation certainly are novrin a very high state of improvement; but themost eminent ventilators will concur in statingthat, unless nearly the whole of the fire-dampcan be removed, other requisites are necessaryfor permanent security.

The explosion of this mine * happened onMay 12, 1814, and destroyed Mr. Mole, theunderviewer, besides ten pitmen, who left ninewidows and twenty-seven children in the ut-most misery and distress.

There is one part of the workings at Hep-burn colliery which has for a considerabletime baffled the skill of every person em-ployed ; and other parts, which at much riskthe owners are enabled to work, cost themabout sixty pounds per month in producinga sufficiency of light from steel-mills, whichare very liable under some circumstances toproduce explosion.

I believe it would be almost impossible tokeep any lamp burning in some parts of thismine now at work, as the prevalence of car-bonic acid is so very great, that combustion

* For former explosion, see p. 40.