DURHAM AND NORTHUMBERLAND. ] 53

Mr. Menzies, in his paper on the ventilationof mines, * “ there are strong deeply-rootedprejudices here of more than fifty years' un-disturbed growth, in favour of the existing sys-tem of ventilation, which the influence of anyindividual, be his genius what it may, cannever remove.” Notwithstanding the opinionsof Mr. Buddie, however, I am much disposedto anticipate great improvements in ventilation,as the subject is now before the public in amore conspicuous manner than ever it wasbefore.

Mr. Buddie, in speaking of the differentindications afforded by the flame of a candlewhen hydrogen gas is present, and of the variouscircumstances by which these indications areeffected, observes, that “ long experience andattentive observation are consequently neces-sary to obtain a thorough practical knowledgeof the art.” This may be, although I foundno difficulty, when down a mine myself, indetecting the different indications of gas underdifferent circumstances ; and I have little he-sitation in saying that there are very few un-cultivated miners, of the least common un-derstanding, who do not understand it as well or

* Thomson’s Annals, p. 284, 1816.