The Latch - The Carrie Furnace

These star like metal objects seen on the stoves of the Carrie Furnace were the latches used to open and close them in order to gain access to their interiors.

The Latch

I had been wondering for some time about what these star-like metal objects were used for. In the audio segment, Mr. Gault answers that question for me. Can you figure it out before you listen to the answer?

A latch used to open and close the stoves at the Carrie Furnace near Pittsburgh, Pennsylvania.