16. John Chalmers Vinson, "Charles Evans Hughes, 1921–1925," in Norman A. Graebner, ed., An Uncertain Tradition: American Secretaries of State in the Twentieth Century (New York, 1961), 134; Waldo H. Heinrichs, American Ambassador: Joseph C. Grew and the Development of the United States Diplomatic Tradition (Boston, 1966), 105.