Instructor in history, University of Pennsylvania, 1914-1917. Instructor in history, Carnegie Institute Technology, 1919-1920. Assistant professor of history University of Pennsylvania, 1920-1930.
Lecturer summer schools Columbia University, U. Texas, University of Tennessee. With Bureau of Labor Statistics, unites states department of Labor, 1931-1951, consultant, since 1952. United States government representative International Labor Conference, Geneva, 1935.
Government representative, coal mines committee International Labor Organisation, 1945-1951, inland transport committee, 1951. Delegate United Nations Science Conference on Conservation and Utilization of Resources, 1949.
Author of books, including: Industrial Society in England toward End of Eighteenth Century, 1924. Industrial History of the United States, 1930. Various government bulletins and pamphlets, notably The Gift of Freedom, 1949 (translations various foreign languages).
American Labor and the American Spirit, 1954, Spanish edition, 1957. Co-author several books, including: Economic History of Europe (with Karpovich and Usher), 1937. Contributor to periodicals, reference works and symposiums.