Media type: E-Article Title: Inventors' Progress. Joachim G. Leithauser , Michael Bullock Contributor: Usher, Abbott Payson imprint: University of Chicago Press, 1960 Published in: Isis Language: English DOI: 10.1086/348854 ISSN: 0021-1753; 1545-6994 Keywords: History and Philosophy of Science ; Earth and Planetary Sciences (miscellaneous) ; History Origination: Footnote: