DURHAM AND NORTHUMBERLAND. 207

which could not be done conveniently whilealterations were making m the downcast pit.

And to descend the upcast pit and proceedunderground to his horses, he would be com-pelled to pass through a region or tornado ofinflammable air, which was looked upon astotally impracticable with lights. This collec-tion of inflammable air arose from particularcircumstances. The Hutton Seam of coals,which runs about twenty-four fathoms underthe Maudlin Seam, and about one hundred andtwenty-five fathoms from the surface, is workedout; the shafts which used to communicate withit are stopped up at the Maudlin Seam, and theair forced down a few staples which remain open,while the waters are permitted to drain into it,which with the gas rapidly and progressively in-crease. The water having in many parts pent thegas up into a narrow compass, and both of themcontinuing to accumulate, the gas is forced torush out through many fissures; and eventhrough the clay scaffoldings which stop upthe shafts. It was found necessary in onepart to bore a hole of three inches diameterfrom the Maudlin to the Hutton Seam, inorder to give the gas vent; and it was thisparticular part which it was necessary the