HARRIOT, THOMAS, an eminent mathematician and astronomer, was born at Oxford in the year 1560.. He took his degree of Bachelor of Arts in 1579, and in 1584 be accompanied Sir Walter Raleigh in his expedition to Virginia, where be was employed iu surveying and mapping the country, and upon his return to England in 1588 he published his ' Report of the New found land of Virginia, the com modities there found to be raised, &c.' Harriet was introduced by Sir Walter Raleigh to the Earl of Northumberland, whose zeal for the promotion of science had led him to ruaiutain several learned men of the day, such as Robert Hues, Walter Warner, and Nathaniel Tarporley. This enlightened nobleman received Harriot into his house, and settled on him an annual salary of 300/., which he enjoyed to the time of his death, in July 1621. His body was interred in St. Christopher's Church, London, and a monument erected to his memory, which, with the church itself, was destroyed by the great fire of 1666. During his lifetime Harriot was known to the world merely as an eminent algebraist ; but from a paper by Zach in the Astro nomical Ephemeris' of the Royal Academy of Soienees at Berlin for the year 1788, it appears that he was equally deserving of eminence as an astronomer. The paper referred to contaius an account of the manuscripts found by Zach at the seat of the Earl of Egremout, to whom thoy had descended from the Earl of Northumberland. From
it we learn that Harriet carried on a correspondence with Kepler concerning the rainbow ; that be had discovered the solar spots prior to any mention having been made of them by Galileo, Scheiner, or Phrysims : also that the satellites of Jupiter were observed by him January 16, 1610, but their first discovery is generally attributed to Galileo, who states that he had observed them on the 7th of that month. A correspondence with Kepler on various optical and other subjects is printed among the letter's of Kepler. Ten years after Harriot's death his Algebra, entitled 'Artie Aualytiem Praxis, ad Aquationea Algebraical nova, expedite, et Generali Methoda, resol vendas,' was published by his friend Walter Warner. It is with reference to this particular work that Des Cartes was accused of plagiarism by Wallis, whose admiration of its author was so high, that he could not even see the discoveries of Vieta anywhere but in the 'Praxis' of Harriot. This charge however has sunk with time, though the French writers still continue to answer it. The geometry of Des Cartes appeared in 1637, six years after the publication of Harriot's Algebra. (Hutton, Dictionary ; Mathematical Tracts, vol. &c.; Montucla, Histoire des Mathematiques, torn. ii., p. 105.)