British Supremacy & Canadian Self-Government, 1839-1854

Proposed Surrender of the Prayer-Book and Articles of the Church of England A Letter to the Lord Bishop of London on Professor Stanley's Views of Clerical and University "Subscription"

Slavery in Pennsylvania A Dissertation Submitted to the Board of University Studies of the Johns Hopkins University in Conformity with the Requirements for the Degree of Doctor of Philosophy, 1910

Nationality and Race from an Anthropologist's Point of View Being the Robert Boyle lecture delivered before the Oxford university junior scientific club on November 17, 1919

The History of University Education in Maryland The Johns Hopkins University (1876-1891). With supplementary notes on university extension and the university of the future

History of Liberia Johns Hopkins University Studies in Historical and Political Science