Person Parsons; William (1800 - 1867); 3rd Earl of Rosse; astronomer Parsons William astronomer Baron Oxmantown 1800 - 1867 British Male York, Yorkshire, England, United Kingdom 17 June 1800 18000617 Monkstown, County Dublin, Ireland 31 October 1867 18671031 Burial: The old church of St Brendan, Parsonstown, County Offaly, Ireland

Astronomer Engineering Mathematics Astronomy Education: At home (until 1818); Trinity College, Dublin; Magdalen College, Oxford. BA (1822); hon LLD (1842, Cambridge); honorary degree from University of Dublin (1863) Career: Lord Oxmanton (1807); MP for the King's County (1821-1835); Lord Lieutenant of the King's County (1831); resigned to pursue other interests (1834); made experiments to improve the reflecting telescope (from 1827); invented a machine for grinding and polishing specula by steam power (1828); succeeded in producing speculae (1838, 1842, 1843) which he used for astronomical observations (begun 1845); on Senate of Queen's University; on Royal Commission of weights and measures; Lord Lieutenant of King's County (from 1831); Colonel of Militia, King's County (from 1834); Representative Peer for Ireland, House of Lords (from 1845); Knight of the Legion of Honour (1855); Chancellor, University of Dublin (1862); died from the removal of a tumour from his knee Honours: KP 1845 Memberships: MRIA (1822); FRAS (1824); Member of Imperial Academy of St Petersburg 1852 Parents: Sir Lawrence William Parson, 2nd Earl of Rosse and Alice Lloyd; succeeded his father as 3rd Earl (1841) Spouse: (m. 14 May 1836) Mary, daughter and co-heiress of John Wilmer Field of Heaton Hall, Yorkshire (died 1885) Children: Sir Charles Algernon Parsons (FRS 1898); three other sons. His research focused on the attempt to resolve the nebular hypothesis. His largest and most expensive telescope project, the construction of a Newtonian reflector with a 6 ft aperture and a 4 ton mirror, known as ‘Leviathan of Parsonstown’, was completed in 1844. Royal Society roles: PRS 1848-1854; VP 1842-1843; 1854-1855 Medals and prizes: Royal Medal 1851 Fellow 08/12/1831 31 Davies Gilbert David Brewster Robert Harry Inglis Henry Kater Alexander Philip Wilson Philip John William Lubbock Charles Savill Onley E Stracey Sources: Bulloch's Roll; DNB; Irish Innovators Obituaries: Proc Roy Soc 1867-1868 vol 16 pp xxxvi-xlii References: A A Mills and R Hall, 'The Production of a Plane Surface. As Illustrated by Specula From Some Early Newtonian Telescopes' in NR 1982-83 vol 37 pp 147-166 Sir Bernard Lovell, 'Herschel's Work on the Structure of the Universe' in NR 1978-9 vol 33 pp 57-75 R K Bluhm, 'A Note on the Origin of the Society's Conversaziones' in NR 1958 vol 13 pp 61-63 Notes: From 1807 to 1841, he was styled as Baron Oxmantown. Parsons P0110.jpg ©The Royal Society International Standard Archival Authority Record for Corporate Bodies, Persons and Families - ISAAR(CPF) - Ottawa 1996 ISBN 0-9696035-3-3 National Council on Archives, Rules for the Construction of Personal, Place and Corporate Names, 1997 https://royalsocietypublishing.org/action/doSearch?ContribAuthorRaw=Parsons%2C+William RCN 10456 RCN 58348 https://pictures.royalsociety.org/image-rs-9554 17 Jun 1800 - 31 Oct 1867 The past Fellows entries are under continuous revision. If you have queries or additional information to contribute, please contact Library@royalsociety.org. Content in external sources is not controlled by the Royal Society and historical sources may include content that is now unacceptable. Reviewed on 10/09/2025 as part of the Name Authority Project update. NA8084 21/11/2001 Andyg Pmab 10/09/2025 RS_NET\VidaM Yes http://viaf.org/viaf/9670149296300680670003 9fcd836e-bdbf-49e6-b525-85c9c0a92c6d