Thomas Savery
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Thomas Savery (c.1650-1715) was an English inventor, born at Shilstone, a manor house near Modbury, Devon, England.
Initially interested in naval applications of engineering (he designed an early paddle-wheel), Savery then became interested in pumping machines. On July 2, 1698 he patented an early steam engine, and in 1702 he published details of the machine in the book Miner's Friend [1], which claimed that it could pump water out of mines. Savery's pump had no piston, but used a combination of atmospheric pressure and steam pressure to raise water. The atmospheric action was limited to lifting a column of water about thirty feet high. This could be increased to about fifty feet by using steam pressure, but the extra stress placed on the boiler by this pressure made it unreliable. The machine was therefore not capable of raising water from the depth of a mine, and the almost only known working versions were used for water-supply pumping in London [2]. However an attempt was made (unsuccessfully) to use one to clear water from a mine at Broadwaters in Wednesbury, then in Staffordshire.[3]
Savery worked for the Sick and Hurt Commissioners. His duties took him to Dartmouth, which is probably how he came into contact with Thomas Newcomen. The Commissioners contracted the supply of medicines to the Navy Stock Company, which was connected with the Society of Apothecaries, John Meres being clerk to both.
In 1701, he obtained an Act of Parliament extending the life of his patent for a further 21 years, to 1733. Rights under this passed to the unincorporated Proprietors of the Invention for Raising Water by Fire. The John Meres was their secretary and treasurer.
By 1712, arrangements were made with Thomas Newcomen to develop Newcomen's more advanced design of steam engine, which was marketed under Savery's patent. Newcomen's engine worked purely by atmospheric pressure, thereby avoiding the dangers of high-pressure steam, and used the piston concept invented in 1690 by the Frenchman Denis Papin to produce the first steam engine capable of raising water from deep mines.[4]
Several later pumping systems may be based on Savery's pump. For example, the twin-chamber pulsometer steam pump was a successful development of it[5]
[edit] External links
[edit] References
- ^ Savery, T., Miner's Friend, text at Rochester University (USA) History Resources URL
- ^ E. I. Carlyle, 'Savery , Thomas (1650?–1715)', rev. Christopher F. Lindsey, Oxford Dictionary of National Biography, Oxford University Press, 2004, accessed 29 April 2006 URL
- ^ S. Shaw, History and Antiquities of Staffordshire (1798-1801) II(1), 120
- ^ L. T. C. Rolt and J. S. Allen, The Steam Engine of Thomas Newcomen (Landmark Publishing, Ashbourne 1997).
- ^ SPP Pumps
