My guess is that they are pulleys, and they just happen to be stored encircling the chimney because it looked pretty. There are two more attached to the ceiling that look to be in a position to actually be used for maneuvering heavy materials and equipment.
My guess is that they are pulleys, and they just happen to be stored encircling the chimney because it looked pretty. There are two more attached to the ceiling that look to be in a position to actually be used for maneuvering heavy materials and equipment.