• Webster's Revised Unabridged Dictionary
    • n Methanometer An instrument, resembling a eudiometer, to detect the presence and amount of methane, as in coal mines.
    • ***
Century Dictionary and Cyclopedia
    • n methanometer An apparatus, devised by Monnier, to determine and indicate automatically the quantity of marsh-gas (methane) in coal-mines. It depends upon the change of level of the mercury in a manometer-tube in which carbon dioxid is formed by the combination of the gas with the oxygen of the air under the action, for example, of an electric spark.
    • ***


Webster's Revised Unabridged Dictionary
Methane, + -meter,