George Medhurst (1759–1827) was an English

mechanical engineer Mechanical may refer to: Machine * Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement * Mechanical calculator, a device used to perform the basic operations of ...

and inventor, who pioneered the use of compressed air as a means of propulsion. His ideas led directly to the development of the first

atmospheric railway An atmospheric railway uses differential air pressure to provide power for propulsion of a railway vehicle. A static power source can transmit motive power to the vehicle in this way, avoiding the necessity of carrying mobile power generating e ...

. He was born in

Shoreham, Kent Shoreham is a village and civil parishes in England, civil parish in the Sevenoaks District of Kent, England. It is located 5.2 miles north of Sevenoaks. The probable derivation of the name is ''estate at the foot of a steep slope''. Steep slo ...

and trained as a clockmaker at Clerkenwell,

London London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary dow ...

, but later became interested in pneumatics. In 1799, he filed a patent for a wind pump for compressing air to obtain motive power and the following year he patented his ‘Aeolian’ engine which used compressed air to power vehicles. In his pamphlet ''On the properties, power, & application of the Aeolian engine, with a plan and particulars for carrying it into execution'', Medhurst proposed the establishment of Aeolian coach services, operated by pumping stations along the route. In 1810, he published ''A new method of conveying letters and goods with great certainty and rapidity by air'', but did not patent the idea. This was followed in 1812 by his ''Calculations and remarks tending to prove the practicability, effects and advantages of a plan for the rapid conveyance of goods and passengers upon an iron road through a tube of 30 feet in area by the power and velocity of air''. He also envisioned carriages running on rails, propelled by a continuous tube beneath the rails, as would later happen in the

. Neither of these ideas was put into practical operation at the time. Shortly before his death in September 1827 Medhurst returned to the idea of pneumatic propulsion with his publication of ''A New System of Inland Conveyance, for Goods and Passengers ... with the velocity of sixty miles in an hour ... without the aid of horses or any animal power.'' ith plates.re
George Medhurst, A new system of inland conveyance for goods and passengers ... with the velocity of sixty miles an hour ... without the aid of horses or any animal power. London: 1827
/ref> Other, more successful, inventions by Medhurst included a steam carriage, a ‘leak proof’ canal lock gate and a variety of weighing and balancing machines.

References

Sources

R. B. Prosser, ‘Medhurst, George (bap. 1759, d. 1827)’, rev. Anita McConnell, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, Jan 200
accessed 9 Jan 2009
p. 240. {{DEFAULTSORT:Medhurst, George People from Shoreham, Kent 1759 births 1827 deaths English inventors English mechanical engineers 18th-century British engineers