 thumb|right|germinal pierre dandelin germinal pierre dandelin (12 april 1794 &ndash; 15 february 1847) was a mathematician, soldier, and professor of engineering. ==life== he was born near paris to a french father and belgian mother, studying first at ghent then returning to paris to study at the Ãcole polytechnique. he was wounded fighting under napoleon. he worked for the ministry of the interior under lazare carnot. later he became a citizen of the netherlands, a professor of mining engineering in belgium, and then a member of the belgian army. ==work== he is the eponym of the dandelin spheres, of dandelin's theorem in geometry (for an account of that theorem, see dandelin spheres), and of the dandelin&ndash;grÃ¤ffe numerical method of solution of algebraic equations. he also published on the stereographic projection, algebra, and probability theory. ==references== * biography in dictionary of scientific biography (new york 1970&ndash;1990). * florian cajori, the dandelin&ndash;grÃ¤ffe method, in a history of mathematics (new york, 1938), 364. * a. s. householder, dandelin, lobachevskii, or grÃ¤ffe?, american mathematical monthly 66 (1959), 464&ndash;466. * a. quetelet, g p dandelin, biographie nationale xiv (brussels,1873), 663&ndash;668. * c. runge, the dandelin&ndash;grÃ¤ffe method, in praxis der gleichungen (berlin-leipzig, 1921), 136&ndash;158. ==further reading== * ==external links== *   
1794_births 1847_deaths 19th-century_mathematicians Belgian_mathematicians Belgian_mining_engineers Dutch_mathematicians