James Rumsey - Work in Shepherdstown

Work in Shepherdstown

Work on a hull had begun in 1785 in Bath by Joseph Barnes. The boat was brought that fall to Shepherdstown. Valve castings, cylinders, and other pieces which had been made in Baltimore and Frederick were installed that December, and the boat was taken downriver to Shenandoah Falls for a test. However, bad weather postponed testing until the following spring. When Rumsey finally tested the boat, it proved very unsatisfactory. The pole-boat mechanism caused the boat to yaw in the current, which disabled the paddlewheel and stopped the boat. In the steam pump, the engine consumed too much steam; the boiler was inadequate.

It may be that, having left the Patowmack Company, Rumsey was loath to work on a propulsion system limited to be used on rivers. Or, lacking money from the Patowmack Company, he wished to concentrate his efforts on the more promising steam pump. At some point in 1786, work on the pole-boat mechanism was abandoned. For a better boiler, he tried a coil of forged iron pipe, which proved to be not only much more efficient but much smaller and lighter. With a functioning steam engine, another problem revealed itself. The single cylinder pump would draw several gallons of water from beneath the boat, send it down a copper pipe to the stern. Because gallons of water were being drawn into the pump at the same time as water was still flowing from it to the stern, the pump was working against itself; several strong strokes and it bound up. This required replacing the copper pipe with a square wooden trunk, that had flapper valves in the bottom to allow water in from the river, to relieve the negative pressure at the pump.

On December 3, 1787, the boat finally made a very successful public demonstration on the Potomac at Shepherdstown.