Consists of articles written by Stewart and others, correspondence, financial material, photoprints, maps, conference material, printed material, and student papers. The collection reflects Stewart's interest in the development of social physics and the many scientific areas that he investigated. The correspondence includes letters with professional colleagues and learned societies, such as Stuart C. Dodd, Ralph E. Himstead, George Webber Mixter, G. Edward Pendray, the American Association of University Professors, the Social Research Council, and the Institute of Navigation; in addition, there is correspondence and reports of conferences on the natural sciences applied to social theory and social physics. Furthermore, there are printing plates for area and population maps of various countries, and nine record center cartons of unprocessed additional material.