Early Oil Lamps

To illuminate their work in a totally dark environment, miners fastened oil lamps such as these to their helmets. The large lamp on the left held lard oil which was poured into the smaller individual lamps on the right. The miner would then attached the smaller lamp to his helmet. After World War I, oil lamps were replaced by carbide and then by electric lamps.   

Photo courtesy: Eileen Mountjoy Cooper, The Rochester and Pittsburgh Coal Company: The First 
One Hundred Years (Indiana, Pennsylvania: Rochester and Pittsburgh Coal Company, 1982), 26.