Gershon Ben-Salomon a Spanish rabbi, native of Catalonia, who lived in the latter half of the 13th century, was the father of rabbi Leon da Bafolas (Ralbag), and wrote Shaar Hash-Shamayim (first printed at Venice, 1547 in four parts). The first treated of the four elements; the second, of astronomy; the third, the heavens and earth, according to the principles of Averroes; the fourth, of theological matters. See Hoefer, Nouv. Biog. Generale, s.v.; Furst, Bibl. Jud. 1:329.