08 BIOLOGICAL SOCIETY OF WASHINGTON. 



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

 cal and Practical," London, 1685.* 



•• 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 

 1 7S7 by Dr. Zach, and later by Prof. Rigaud, of Oxford, who. 

 in 1833, published in his 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." \ 



A posthumous work, " Artes Analytical Praxis ad ^Equationes 

 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 

 Chyrometrica." 



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. 



1 Good and Gregory: Pantologia, vol. v. 



