This lamp is an Improved Hailwood made in Leeds by Ackroyd and Best from around 1914. These lamps were used in mines until 1937, when tightening regulations made them obsolete as they were no longer apporved for undergound use.
Hailwood and Ackroyd (as the company was then known) began recycling the lamps with blue glass and sold them as air raid or emergancy lamps during the Second World War. They would be used to highlight dangers in a blue light, like exposed gas mains, which would not break blackout conditions.
