Safety lamp: Gray type
1893-1899
Safety lamp: Gray type, for coal miners’ gas testing; Hydrogen cylinder, spare; Mahogany box, for carrying coal miners’ gas testing safety lamp and spare hydrogen cylinder, originally designed by Thomas Gray, design modified by Dr. Frank Clowes, based on J. Ashworth's patent Hepplewhite-Gray type, for gas testing and made by Stanley, Derby, Derbyshire, England, 1893-1899