Last week Will and Eric were preparing to photograph the steam chest from Monitor’s port Worthington Pump. This component houses the slide valve which fed steam from the boilers to drive the pump’s steam piston. Noticing that the valve rod packing seal fitting appeared to have loosened up during treatment, they were able to remove it intact and discovered that the fibrous packing material was still inside. The organic packing material, which resembles a tightly twisted rope, was wound around the wrought iron valve rod and packed tightly into a packing chamber. It may have been treated with lead or some type of natural oil or tallow to improve the sealing properties. When the pump was functioning on the Monitor, this material would have kept the steam sealed inside where it could do the most work, and prevented waste of valuable boiler pressure. This find is exciting! Although we know there were a number of packing seals used on the Monitor, this is the first one we have found intact! Look for more on the packing material soon!