John Theophilus Desaguliers

Infobox Scientist
name = John Desaguliers
box_width = 300px

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image_width = 300px
caption = John Theophilus Desaguliers (1683-1744)
birth_date = 13 March 1683
birth_place = La Rochelle, France
death_date = 29 February 1744
death_place = Covent Garden, London, England
residence = flag|England
citizenship =
nationality = flag|England|name=English
ethnicity = flag|France|name=French
field = Natural philosopher and engineer
work_institutions = University of Oxford
alma_mater = Christ Church, Oxford
doctoral_advisor =
academic_advisors = John Keill
doctoral_students =
notable_students = Stephen Demainbray
Willem 's Gravesande
Stephen Gray
known_for = Planetarium
author_abbrev_bot =
author_abbrev_zoo =
influences = Isaac Newton
influenced =
prizes = Copley Medal
religion = Anglican
footnotes =

John Theophilus Desaguliers (pronounced day-za-güly-ay) (13 March 1683 – 29 February 1744) was a natural philosopher born in France. He was a member of the Royal Society of London beginning 29 July 1714. He was presented with the Royal Society's highest honour, the Copley Medal, in 1734, 1736 and 1741, the 1741 award being for his "discovery of the properties of Electricity".ref|copleymedalref|royalsociety He studied at Oxford, became experimental assistant to Sir Isaac Newton, and later popularized Newtonian theories and their practical applications. He invented the planetarium.

Biography

Born in La Rochelle, Desaguliers was an immigrant to England from France. He was born into a Huguenot (Protestant) family and fled to England at the age of 11 (1694) to escape the consequences of the Revocation of the Edict of Nantes. He was educated at Christ Church, Oxford, and succeeded Dr. Keill in reading lectures on experimental philosophy at Hart Hall. He was the first who introduced the reading of lectures in London, where he had for his auditors not only the learned and the great, but also George I and George II and the royal family. In 1714, he was chosen a member of the Royal Society, to whose Transactions he communicated some valuable papers. In 1718, he completed his degrees at Oxford as bachelor and doctor of laws. Desaguliers' reputation as a scientist was sealed not only by his three awards from the Royal Society, but also by publication of a two volume work entitled "A Course of Experimental Philosophy". Publication of the first volume coincided with the year he first received the Copley Medal (1734), while the second volume's publication came 10 years later in 1744, the year of his death. The first volume concerns theoretical and practical mechanics with an explanation of the basics of Newtonian physics. The second volume contains material oriented toward practical application of scientific findings.ref|course_exp_phil

An inventor as well as a scientist, Desaguliers improved upon the steam engine design of Thomas Savery through the addition of a safety valve. He also designed methods for heating liquid boilers with steam rather than fire, presumably increasing their safety significantly.ref|boilers

Additionally, Desaguliers was a Freemason, elected as the third Grand Master in 1719, Deputy Grand Master in 1723 and 1725 of the newly formed Premier Grand Lodge of England.

Desaguliers was also a priest in the Church of England, and was for many years the Rector of St Lawrence, Little Stanmore (sometimes called Stanmore Parva), at Edgware in Middlesex, and domestic chaplain to James Brydges, 1st Duke of Chandos. The church at Stanmore was at the edge of the duke's estate, Canons Park. Here Desaguliers would no-doubt have been party to the first performances of the so-called Chandos Anthems, by George Frideric Handel, who was then, like Desaguliers, a member of the Duke's household. Desaguliers played an important role in directing the Duke's patronage of scientific and engineering projects.

There are at least three surviving portraits of Desaguliers dating to 1725 (42 years of age), all held by the National Portrait Gallery in London and available for on-line viewing.ref|portraits

Personal life

On 14 October 1712 he married Joanna Pudsey, daughter of William and Anne Pudsey of Kidlington, near Oxford. They had four sons and three daughters, for most of whom they acquired aristocratic godparents, but only two children survived beyond infancy: John Theophilus (1718–1751) graduated from Oxford, became a clergyman, and died childless, while Thomas Desaguliers (1721–1780) led a distinguished scientific military career.

Decline

Desaguliers had long suffered from gout every winter, and died after several months of severe illness at his home in the Bedford Coffee House, Covent Garden, London, on 29 February 1744; he was buried on 6 March in the Savoy Chapel, Savoy Street, London.

Notes

# [http://www.royalsoc.ac.uk/page.asp?id=1744 Copley archive winners 1799-1731] . " [http://www.royalsoc.ac.uk/ The Royal Society] ". Retrieved 2005-02-12. The work honored is not detailed on this site.
# [http://www.royalsoc.ac.uk/trackdoc.asp?id=776&pId=1727 Fellows of the Royal Society - D] . " [http://www.royalsoc.ac.uk/ The Royal Society] ". Retrieved 2005-02-12. This PDF document also contains birth and death dates.
# Gory, Paul. [http://pollagoras.free.fr/ouvrage/desaguliers_livres/a_course_of.htm A Course of experimental philosophy] . Retrieved 2005-02-12. Translated French=>English using Babel Fish, 2005-02-12.
# [http://www.scienceandsociety.co.uk/results.asp?
] " [http://www.scienceandsociety.co.uk/index.asp Science & Society Picture Library] ". Retrieved 2005-02-12.
# [http://www.npg.org.uk/live/search/person.asp?LinkID=mp15842 John Theophilus Desaguliers (1683-1744), Natural philosopher. Sitter in 3 portraits] . " [http://www.npg.org.uk/live/index.asp The National Portrait Gallery] ". Retrieved 2005-02-12.

References

* Mackey, Albert G., Encyclopedia of Freemasonry, An, The Masonic History Company, Chicago, 1966.
* Baker, C. H. Collins, and BaKer, Muriel (1949) "James Brydges First Duke of Chandos" Oxford : Clarendon Press
* Carpenter, A. and Pink, A. (2006) [http://www.ucl.ac.uk/~ucypanp/deslet.htm "The letters of James Brydges Earl of Carnarvon and later Duke of Chandos (1674–1744) to John Theophilus Desaguliers (1683–1744)"] . An ongoing web project: UCL and Loughborough universities, UK

ee also

* Stephen Gray

External links

* [http://freemasonry.bcy.ca/biography/desaguliers_j/desaguliers_j.html Masonic biography]
* [http://chem.ch.huji.ac.il/history/desaguliers.html Scientific biography]
* [http://www.ingentaconnect.com/content/bpsoc/bjp/2000/00000091/00000002/art00009 British Journal of Psychology]