Keywords: Thomas Young Hall's patent safety lamps 1854.jpeg Thomas Young Hall's patent safety lamps included in A Treatise on the Extent and Probable Duration of the Northern Coal Field by T Y Hall 1854 The original from which this has been scanned is in the https //en wikipedia org/wiki/North_of_England_Institute_of_Mining_and_Mechanical_Engineers North of England Institute of Mining and Mechanical Engineers It is reference Tracts vol 39 pp200-201A The scan and the upload to Wiki Commons have been made with the permission and direction of their librarian Jennifer Kelly PD-old-70-1923 PD-US North of England Institute of Mining and Mechanical Engineers Mining lamps Mining images |