XJF359013 John Dalton, engraved by William Henry Worthington, c.1814 (engraving) by Allen, Joseph (1770-1839) (after); Private Collection; (add.info.: John Dalton (1766-1844) English chemist, meteorologist and physicist; developed pioneering work on atomic theory and colour blindness; he was President of the Manchester Literary and Philosophical Society; developed the law of multiple proportions;); English, out of copyright.