**HARRIOT,** or Harriott, **THOMAS** (1560–1621), English mathematician and astronomer, was born at Oxford in 1560. After studying at St Mary Hall, Oxford, he became tutor to Sir Walter Raleigh, who appointed him in 1585 to the office of geographer to the second expedition to Virginia. Harriot published an account of this expedition in 1588, which was afterwards reprinted in Hakluyt’s *Voyages*. On his return to England, after an absence of two years, he resumed his mathematical studies, and having made the acquaintance of Henry Percy, earl of Northumberland, distinguished for his patronage of men of science, he received from him a yearly pension of £120. He died at London on the 2nd of July 1621. A manuscript of Harriot’s entitled *Ephemeris chrysometria* is preserved in Sion College; and his *Artis analyticae praxis ad aequationes algebraicas resolvendas* was published at London in 1631. His contributions to algebra are treated in the article Algebra; Wallis’s *History of Algebra* (1685) may also be consulted. From some papers of Harriot’s, discovered in 1784, it would appear that he had either procured a telescope from Holland, or divined the construction of that instrument, and that he coincided in point of time with Galileo in discovering the spots on the sun’s disk.

See Charles Hutton, *Mathematical and Philosophical Dictionary* (1815), and J. E. Montucla, *Histoire des mathématiques* (1758).