A traditional candlestick Stephenson lamp with a domed top and a screw lock. Made by John Mills of Newcastle in around 1865.
Stephenson lamps look from the outside like Davy lamps but have a tube of glass inside the gauze. Air reaches the flame through a set of holes drilled in the base and leave through the holes in the domed top. This meant they didn’t suffer in strong ventilation air currents but the glass could soot-up, causing the glass to go black.
John Mills worked closely with the lamp inventor W. R. Clanny and became sole maker of his design in around 1839.