Notable Descendant of Sir Robert Belknap: Henry Cavendish, Discoverer of Hydrogen

Notable Descendant of Sir Robert Belknap (abt 1330-1401): Henry Cavendish, Discoverer of Hydrogen.  British natural philosopher, scientist, and an important experimental and theoretical chemist and physicist, Cavendish is known for researches into the composition of atmospheric air, properties of different gases, synthesis of water, the law governing electrical attraction and repulsion, a mechanical theory of heat, and calculations of the density (and hence the mass) of the Earth that is famously known as the “Cavendish experiment.”  (The result that Cavendish obtained for the density of the Earth is within 1 percent of the currently accepted figure.)  Cavendish is noted for his discovery of hydrogen or what he called “inflammable air”.  He described the density of inflammable air, which formed water on combustion, in a 1766 paper “On Factitious Airs”.  (Antoine Lavoisier, the “father of modern chemistry,” later reproduced Cavendish’s experiment and gave the element its name.)  Cavendish was born 10 October 1731 in Nice, Kingdom of Sardinia (now France), where his family was living at the time.  His father was Lord Charles Cavendish (1704-1783; son of William Cavendish, 2nd Duke of Devonshire), a Whig politician and, as winner of the Copley Award, a noted scientist in his own right.  His mother was Anne Grey, fourth daughter of Henry Grey, 1st Duke of Kent.  Cavendish was a shy man who was uncomfortable in society and avoided it when he could.  He conversed little, always dressed in an old-fashioned suit, and developed no known deep personal attachments outside his family.  Cavendish was regarded by many as eccentric.  For example, he only communicated with his female servants by notes.  Cavendish died 24 February 1810 as one of the wealthiest men in Britain.  He was buried, along with many of his ancestors, in Derby Cathedral.  The University of Cambridge’s Cavendish Laboratory was endowed by one of his later relatives in his honor.  Cavendish is a direct descendant of Sir Robert Belknap through at least four well-documented ways–once through the “Cavendish-Cecil-Cooke” line via Sir Robert Belknap’s great granddaughter Eleanor (or Elizabeth) Belknap; twice through the “Howard-Audley-Grey-Wotton” line via another great granddaughter of Sir Robert, Anne (sister to Eleanor/Elizabeth); and once through the “Devereaux-Ferrers” line via a granddaughter of Sir Robert, Elizabeth Belknap daughter of Hamon.  Through all four lineages, Cavendish is 14 generations from Sir Robert Belknap, making him Sir Robert’s 11th great grandson–four times! For further information on Balfour, see:  https://en.wikipedia.org/wiki/Henry_Cavendish

Categorised in: Sir Robert Belknap Descendants

This post was written by Brent J. Belnap