Vtg Friemann & Wolf Brass AirTurbo AirLamp Safety Lamp for Explosive Atmospheres

Description

Vintage Friemann and Wolf AirTurbo Safety Lamp / AirLamp
This vintage safety lamp was designed for use in explosive atmospheres. It's all-brass body prevents any dangerous sparking or static.
The working condition of this lamp is unknown, however, however it appears to be in good condition. There does not appear to be a bulb, but the lens is intact. I have made no attempt to open the lamp to examine the condition of the air turbine. The weight of the lamp is approximately 32 pounds and is approximately 12" long and 8" in diameter (at widest point, the lens is ~7.5")
I do not know the age of this lamp, though based on the markings, I am sure that it is not a modern version of the Wolf Safety AirLamp. Friemann and Wolf was established in 1884 and began manufacturing mining lamps in 1907. Compressed air operated lamps were introduced in the 1930s.