38 BIOLOGICAL SOCIETY OF WASHINGTON. 



posed by Dr. Wallis in his " Treatise of Algebra, both Theoreti 

 cal and Practical," London, 1685.* 



kt Oldys, in his Life of Sir Walter Raleigh, has shown," says 

 Stith, " that the famous French philosopher, Descartes, bor 

 rowed much of his light from this excellent mathematician, and 

 that the learned Dr. Wallis gave the preference to Harriot's im 

 provements before Descartes', altho' he had the advantage of 

 coming after and being assisted by him." f 



Harriott's papers were left after his death in the possession of 

 the Percy family at " Petworth," where they were examined in 

 1787 by Dr. Zach, and later by Prof. Rigaud, of Oxford, who, 

 in 1833, published m ^ s supplement to the works of James 

 Bradley, " An Account of Thomas Harriot's Astronomical Pa 

 pers." His observations on Halley's comet in 1607 are still re 

 ferred to as being of great importance. Zach pronounced him 

 an eminent astronomer, both theoretical and practical. " He was 

 the first observer of the solar spots, on which he made a hundred 

 and ninety-nine observations ; he also made many excellent obser 

 vations on the satellites of Jupiter, and indeed, it is probable 

 that he discovered them as early if not earlier than Galileo." J 



A posthumous work, " Artes Analytical Praxis ad yEquationes 

 algebraicas nova, expedita et generali Methodo resolvendas, e 

 posthumis Thomas Harriot," was published in 1631 by his 

 friend and associate, Walter Warner, and there is in the library 

 of Sion College a manuscript work of his entitled " Ephemeris 

 Chy rometrica . " 



Wood says that, "notwithstanding his great skill in mathe 

 matics, he had strange thoughts of the scriptures, always under- 



* It would appear, however, that Wallis may have been too enthusiastic 

 in his admiration of the English mathematician. Hallam states that he 

 ascribed to Harriott a long list of discoveries which have since been re 

 claimed for Cardan and Vieta. 



t STITH : History of Virginia, 1747, p. 20. 



t GOOD AND GREGORY : Pantologia, vol. v. 



