Sauer, Carl Ortwin, 1889-1975, American geographer, b. Warrenton, Mo., grad. Univ. of Chicago (Ph.D., 1915). Sauer was a professor for over 50 years at the Univ. of California at Berkeley, where he built a distinguished graduate school. A great influence on a generation of geographers, he sought to unify the areas of physical and human geography through an essentially historical methodology. Sauer advocated a "humane" use of the environment, pointing to ancient and modern rural cultures as examples. Among his 21 books and monographs are Agricultural Origins and Dispersals (1952) and Northern Mists (1968).