James Rumsey

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James Rumsey (1743-1792) was an American mechanical engineer who exhibited a boat propelled by machinery in 1787 on the Potomac River at what is now Shepherdstown, West Virginia, before a crowd of local notables, including Horatio Gates. A pump driven by steam power ejected a stream of water from the stern of the boat and thereby propelled the boat forwards.

The demonstration occurred 20 years before Robert Fulton constructed and demonstrated the Clermont. Benjamin Franklin was a member of the Rumseian Society which had been formed to promote the project. Franklin took a ship back from France, and while onboard also thought of propelling a boat by water jet; at the same time, Rumsey was actually constructing such a boat. Daniel Bernoulli (1700-1782) originated the idea of propelling watercraft in that way.

After moving to England in 1788, Rumsey was able to take out four patents before his death there in 1792. While some of these relate to steamboats (like his water-tube boiler design, which made the steam engine much smaller and more efficient) most are concerned with hydrostatics and water power. His 1791 Patent has all the pumps, motors and hydraulic cylinders of fluid power engineering. By September of 1792 he had arrived at a true water turbine, almost 40 years before it would be next invented in France, but as he died in December he did not live long enough to feature it in a patent.

[edit] Sources

Source for date of Rumsey successful trial: A Plan Wherein the Power of Steam is Fully Shewn by James Rumsey, Jan 2, 1788, Rare Book Room, Library of Congress.

Source for name of group formed by Franklin to support Rumsey: letter from James Rumsey to his brother-in-law Charles Morrow on May 14, 1788, as he was preparing to leave for England sent by the Society.

Source for Franklin's ideas on jet propulsion can be found in his Maritime Observations, 1785.

Source for Rumsey's English inventions; British Patent Numbers (dates): #1673 (1788); #1738 (1790); #1825 (1791); #1903 (1792), The British Library.

For his turbine: Joseph Barnes to John Vaughn, Sept. 21, 1792; Joseph Barnes: Essay on Watermills, 1793 Rumseian Society papers, American Philosophical Society archives, Philadelphia, PA.