Richardson, William (1740–1820), cleric, geologist, agriculturist, and pamphleteer, was probably born at Castleroe, near Coleraine, Co. Londonderry, the only son of Charles Richardson (d. 1743) and his wife Sarah, daughter of Hercules Heyland of Coleraine. He was educated at TCD (BA, 1763; MA, 1766; BD, 1775; DD, 1778), and was admitted to fellowship in 1766 but resigned in September 1783 on taking up the living of the parish of Clonfeacle and Moy, Co. Tyrone, in the diocese of Armagh.
Richardson was a prolific author, principally on geological and agricultural subjects. His geological works were published between 1802 and 1817 as pamphlets or as papers, largely in the Transactions of the Royal Irish Academy, of which he was a member. These included Account of the whynn dykes in the neighbourhood of the Giant's Causeway, Ballycastle, and Belfast (1803) and On the volcanic theory (1806). In these he described the basalt of the north-east Antrim coast where he resided during the summer months, and along with the chemist and mineralogist Richard Kirwan (qv) he disputed the arguments of the geologist James Hutton and Nicolas Desmarest, who stated that these and similar rocks were produced by volcanic or igneous processes. In about 1799 Richardson found examples of the fossil marine ammonites in the basalts at Portrush, which proved to him and to others that basalt was a precipitated rock, which they thought was deposited from the biblical flood waters. It was later shown that he was mistaken and that the fossils were in fact contained in rock that had been heated to a high temperature by an igneous intrusion close by, and superficially resembled basalt.
He later turned his hand to agriculture and promoted the growing of fiorin grass Agrostis alba var. stolonifera as a source of winter hay, which he said could alleviate the poverty of the tenant classes. His important agricultural pamphlets included An elementary treatise on the grasses of Ireland (1806), The utility of fiorin grass (1811), and An essay on agriculture (1818). In two pamphlets (1807, 1809) he outlined his scheme for draining and reclaiming the bog of Allen and other bogs to the north for use as meadows for grazing. Richardson claimed that he was largely responsible, together with Thomas Knox (qv) of Dungannon, for the establishment in 1796 of the loyalist Irish yeomanry, set up at a time of increased political instability, and documented his role in the pamphlet Origin of the Irish yeomanry (1801). William Richardson died 24 September 1820 at the Glebe House, Clonfeacle.
He married (1785) Hannah (1749/50–1839), daughter of Mark McCausland and Elizabeth Heyland; they had at least two sons. In 1818 their second son, Thomas Wolfe Richardson, was appointed to the perpetual curacy of Moy, which was formed out of Clonfeacle. The only known likeness of William Richardson is a caricature published in Dublin c.1809, which shows him scything grass in a field close to his church. His geological collections were donated to TCD but cannot now be identified.