XJF134150 Henry Cavendish, F.R.S. (1731-1810), 19th c. (pen, ink and wash) by English School, (19th century); Private Collection; (add.info.: British natural philosopher, scientist, theoretical chemist and physicist. experiments with air and heat; Fellow of the Royal Society from 1760 till his death; 1781 showed that hydrogen and oxygen together produced water; in 1798 he published a paper accurately calculating the density or mass of the earth; qualities finally recognised late 19th century when the University of Cambridge named its new Cavendish Laboratory after him; Discovery of hydrogen.); English, out of copyright.