English astronomer, botanist, and mathematician; born at Cambridge 1739; died in London 1775; son of Israel Lyons. In his earliest youth he showed a remarkable aptitude for study, especially for mathematics. He began in 1755 the study of botany, which he continued till his death. In 1758 he published a "Treatise on Fluxions," dedicated to his patron, Dr. Smith, master of Trinity College; and in 1763 "Fasciculus Plantarum Circa Cantabrigiam Nascentium, Quæ post Raium Observatæ Fuere." Lyons was invited by Sir Joseph Banks, president of the Royal Society, who had received his earliest lessons in science from him, to lecture at Oxford in 1762, but he soon returned to Cambridge. He was appointed by the board to accompany Captain Phipps (afterward Lord Mulgrave) on a voyage to the north pole in 1773. On his return he married and settled in London, where he died in about a year. At the time of his death he was engaged in publishing some papers of Edmund Halley, secretary of the Royal Society.
- Nichols, Literary Anecdotes, ii. 327-328 and iii. 660, London, 1812;
- Maunders, Treasury of Biography;
- Carmoly, Médecins Juifs, Brussels, 1844;
- Jew. Chron. Nov. 27, 1863.