Bavarian mathematician; born at Friesenhausen about the middle of the eighteenth century; lived at Berlin, and later at Hunfalu and Ujhely, Hungary; died at Gyula-Fehérvá March 23, 1828. Till the age of thirty he occupied himself with the study of the Talmud. Then he spent ten years in studying algebra, astronomy, mechanics, and optics, and wrote essays on these sciences. He wrote: "Kelil ha-Ḥeshbon," a Hebrew manual of algebra and geometry, Berlin, 1796; "Mosedot Tebel," a treatise on astronomy, in which he explains the Copernican system. This work, published in Vienna, 1820, contains also a proof for the eleventh axiom of Euclid and a testament to his children. Friesenhausen was the first to advocate the establishment of a rabbinical seminary in Hungary, and for this purpose prepared a plan which he submitted to the prince palatine Josef as early as 1806.
Categories: [Jewish encyclopedia 1906]