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Humphrey Lloyd 1831-1843

Humphrey Llyod 1831-1843Humphrey Lloyd was born in Dublin on 16th April 1800 to Bartholomew Lloyd (a future Provost of Trinity) and Eleanor McLaughlin. He was educated at White’s School in Dublin and enrolled in Trinity College on 3rd July 1815, aged 15, becoming a Scholar in 1818. He graduated BA in 1820, MA in 1827, BD and DD in 1840. He was elected a Fellow in 1824. In 1831 he succeeded his father as the tenth Erasmus Smith’s Professor of Natural and Experimental Philosophy, serving until 1843.

He worked mainly in the field of optics, making his most notable discovery in 1833.  William Rowan Hamilton had earlier predicted that a ray of light emerging from a biaxial crystal would be refracted into a cone of rays, a phenomenon known as conical refraction. Lloyd was able to observe conical refraction from a crystal of the mineral aragonite. A demonstration of conical refraction can be seen in the current Tercentenary Exhibition. He assumed responsibility for the magnetic observatory in Trinity and carried out magnetic surveys of Ireland under the auspices of the British Association and the Royal Society.  Observing stations were set up in Britain and India to take geo-magnetic measurements such as vertical and horizontal components of the Earth’s magnetic field and its inclination. In 1841, along with James McCullagh and Thomas Luby, he recommended that a school of civil engineering be established in Trinity, which was achieved later that year. From 1846 to 1851 he served as the president of the Royal Irish Academy. In 1867 he was elected as the Provost. He encouraged research as a principal function of the College. His publications include ‘A treatise on light and vision’ (1831), ‘Lectures on the wave theory of light’ (1836 and 1841), and ‘The elements of optics’ (1849). Over his career he published 8 books and 64 papers. He married Dorothea Bulwer in 1840; the couple had no children. He died on 17th January 1881 in the Provost’s house. His portrait hangs in the Fitzgerald Building in Trinity College.

 

Sources

  1. Thomas Ulick Sadlier (1935), Alumni Dublinenses: a register of students, graduates, professors, and Provosts of Trinity College in the University of Dublin (1593-1860), Thom Co Ltd, page 505, https://digitalcollections.tcd.ie/concern/works/70795b624
  2. TCD (2021), Humphrey Llyod, TCD, https://www.tcd.ie/Provost/history/former-Provosts/h_lloyd.php
  3. David Murphy (2009), Llyod, Humphrey, Dictionary of Irish Biography https://www.dib.ie/biography/lloyd-humphrey-a4858
  4. J. Connor and E. Robertson (2016), Humphrey Llyod, St Andrews, https://mathshistory.st-andrews.ac.uk/Biographies/Lloyd_Humphrey/
  5. Eric Finch (2016), Three Centuries of Physics in Trinity College Dublin, Living Edition
  6. Image of Humphrey Lloyd, By Unknown author - http://www.orden-pourlemerite.de/mitglieder/humphrey-lloyd?m=3&u=3  , Public Domain, https://commons.wikimedia.org/w/index.php?curid=27539048