In Germany David Gans wrote on astronomy, and also the historical work Zemah David (Prag, 1592).
D-Mannose, first prepared by oxidizing d-mannite, found in plants and manna-ash (Fraxinus ornus), was obtained by Tollens and Gans on hydrolysing cellulose and by Reis from seminine (reserve cellulose), found in certain plant seeds, e.g.
Gustav Heinrich Gans, Edler zu Putlitz >>
Early in the 19th century he was associated with Gans Moser and Heine in an association which the last named called "Young Palestine."
Edward Gans (q.v.) and Heinrich Gustav Hotho carried the method into special spheres of inquiry.