GERMAN SCIENTISTS AND THINKERS, 20th CENTURY. A collection of approximately 29 autograph letters and manuscripts, including: Leo FROBENIUS (a poem, 'Weltbild einer Bamberger Stunde', 27 January ?1933, one page, large 4to), Joseph Schumpeter (economist), Max von Laue (to Clara von Drygalski, 1949, a letter of condolence on the death of her husband, the geographer and polar explorer Erich Dagobert von Drygalski), Lujo Brentano (postcard, 1924, referring to an article on the state of the German economy), Eugen Boehm-Bawerk (to the Viennese nerve doctor Heinrich Obersteiner, 1910), Eduard Suess (4 letters to Obersteiner and his wife, 1907-10), Wenzeslaus Gleispach (2 letters, 1922), Victor Kienböck (1936, with an inscribed visiting card and two related items), Paul Laband (1910), Adolf Wach (son-in-law of Felix Mendelssohn, 1909) and Hans Kelsen (14 letters and a postcard to his brother Fritz, 1968-69). (29)