While it is impossible to mention even a small portion of the publications of more than usual interest during the last fifteen years, there are a few that may be mentioned as evidence of the influence of the University in the world of letters and scholarships. These, omitting numerous textbooks and aside from the volumes issued in the University Humanistic Series and others, include, "The Acropolis at Athens," (1908), by Professor M.L. D'Ooge; "The Will to Doubt, an Essay in Philosophy for the General Thinker," (1907), by Professor A.H. Lloyd; a series of works on psychology by Professor W.B. Pillsbury, including "Attention," (1908); "The Psychology of Reasoning," (1910); "The Fundamentals of Psychology," (1916), and "The Psychology of Nationality and Internationalism," (1919). Professor R.M. Wenley, head of the Department of Philosophy has also written a number of books which include, "Modern Thought and the Crisis in Belief," (1909); "Kant," (1910); "The Anarchist Ideal," (1913); and the "Life of George S. Morris," (1917). Professor R.W. Sellars of the same Department has written, "Critical Realism," (1916); "The Essentials of Logic," (1917); "The Essentials of Philosophy," (1917); and "The Next Step in Religion," (1918), while Professor D.H. Parker is the author of two volumes entitled "The Self and Nature," (1917), and "The Principles of AEsthetics," (1920). The Department of History includes on its Faculty a number of men whose books have attracted more than a passing attention. Professor C.H. Van Tyne has written among other books, including several textbooks, "The Loyalists in the American Revolution," (1902), and "The American Revolution," (1905); while others to be mentioned are Professor A.L. Cross, whose "History of England and Greater Britain" appeared in 1914; Professor U.B. Phillips, "The Life of Robert Toombs," (1913), and "American Negro Slavery," (1918); and Professor E.R. Turner, "The Negro in Pennsylvania," (1911), and "Ireland and England, in the Past and at Present," (1919). Professor Henry C. Adams has written a number of books on economics and accounting, particularly "American Railway Accounting," (1918). It is worthy of note that he spent two years in China installing a system of railway accounting for the Chinese government. Other volumes which should be noted are: "Social Problems," (1918), by Professor Charles H. Cooley; "Characteristics of Existing Glaciers," (1911), and "Earth Features and their Meaning," (1912), by Professor William H. Hobbs; "The Hindu-Arabic Numerals," (1911), by Professor L.C. Karpinski, and the "Catalogue of the Stearns Collection of Musical Instruments," (1919), prepared by Professor A.A. Stanley.