Pipe radiators at Eastern State Penitentiary
Although no longer working, these pipe radiators at America's first penitentiary show how the Dead Men once heating large spaces such as ... all » this one. Each pipe is threaded left-hand on one side and right-hand on the other. The Dead Men had to screw the entire maze of piping together at the same time, a small turn on each pipe, one after the other, over and over again, and the pipes had to pitch slightly so that the water formed as the steam condensed could flow by gravity back to the boiler. This is the piping trades at their best.