Kirwan, Richard (1733–1812), chemist, mineralogist, geologist, and meteorologist, was born 1 August 1733 at Cloughballymore, Co. Galway, second son among four sons of Martin Kirwan and Mary Kirwan (neé French). He was educated first in Ireland and later at Poitiers, France, and for the priesthood at St Omer, where he excelled at classics and was appointed professor of humanities. He returned to Ireland in 1755 on the death of his elder brother in a duel, and succeeded to the family estates at Cregg, Co. Galway, and an income of £4,000 a year. He studied law in London from 1761 and was called to the Irish bar in 1766.
Soon afterwards he abandoned law and devoted himself to the study of chemistry, and returned to Galway in 1772. Five years later he returned to London, and was elected FRS in 1780. His house became a frequent meeting place for scientists including Joseph Priestley, Joseph Banks, and Henry Cavendish, and there he carried out much experimental work in chemistry. His important contributions included his titrimetric determination of iron with ferrocyanide, his tabulation of specific heats based on water, and his promotion of the theory of phlogiston, which he argued was a constituent of all combustible substances; later this idea was shown by Lavoisier and others to be incorrect. He took up residence at 6 Cavendish Row, Dublin (1787). In Ireland he arranged for the purchase of the important Leskean collection of minerals by the Dublin Society.
He was a prolific author of papers and books on chemistry, mineralogy, meteorology, and other subjects, and frequently published in the Transactions of the RIA. His books appeared in multiple editions in English, and four were translated into French, German, Spanish, or Russian. He kept a daily record of Dublin weather for many years. He opposed the views of the Scottish farmer James Hutton, who argued that the duration of the earth's history was infinite; Kirwan subscribed to the biblical chronology. His geological publications included the important books Elements of mineralogy (1784; 2nd ed. 1794), which was the first English-language text on the subject, and Geological essays (1799). He was awarded the Copley medal of the Royal Society and was president of the RIA (1799–1812). He assembled two major libraries: the first was captured by a privateer on route to London and is now in Salem, Massachusetts; the second was sold after his death, with the exception of the philosophical and geological volumes, which were bequeathed to the RIA. He married (1757) Anne (d. 1765), daughter of Sir Thomas Blake of Menlough Castle, Galway, and had two daughters, Maria Theresa and Eliza. He was known for his eccentric behaviour in later life, his fear of the cold and of flies, but much of this may be attributed to various medical conditions, including a difficulty in swallowing, which necessitated his eating alone. He died in Dublin 1 June 1812 while starving a cold, and was buried at St George's church, Hill St., Dublin. Portraits are in the RDS and RIA, and his burning-glass is in the RDS.