Produced by Gallica (http://gallica.bnf.fr/), Clare Boothby, Victoria Woosley and the Online Distributed Proofreading Team at https://www.pgdp.net. THE Psychological Review _EDITED BY_ J. McKEEN CATTELL and J. MARK BALDWIN COLUMBIA UNIVERSITY PRINCETON UNIVERSITY _WITH THE CO-OPERATION OF_ ALFRED BINET, ÉCOLE DES HAUTES-ÉTUDES, PARIS; JOHN DEWEY, H.H. DONALDSON, UNIVERSITY OF CHICAGO; G.S. FULLERTON, UNIVERSITY OF PENNSYLVANIA; G.H. HOWISON, UNIVERSITY OF CALIFORNIA; JOSEPH JASTROW, UNIVERSITY OF WISCONSIN; G.T. LADD, YALE UNIVERSITY; HUGO MÜNSTERBERG, HARVARD UNIVERSITY; M. ALLEN STARR, COLLEGE OF PHYSICIANS AND SURGEONS, NEW YORK; CARL STUMPF, UNIVERSITY, BERLIN; JAMES SULLY, UNIVERSITY COLLEGE, LONDON. H.C. WARREN, PRINCETON UNIVERSITY, _Associate Editor and Business Manager_. * * * * * Series of Monograph Supplements, Vol. IV., No. 1 (Whole No. 17), January, 1903. HARVARD PSYCHOLOGICAL STUDIES, Volume I CONTAINING Sixteen Experimental Investigations from the Harvard Psychological Laboratory. EDITED BY HUGO MÜNSTERBERG. PUBLISHED BI-MONTHLY BY THE MACMILLAN COMPANY, 41 N. QUEEN ST., LANCASTER, PA. 66 FIFTH AVENUE, NEW YORK. AGENT: G.E. STECHERT, LONDON (2 Star Yard, Cary St., W.C.) Leipzig (Hospital St., 10); PARIS (76 rue de Rennes). PRESS OF THE NEW ERA PRINTING COMPANY LANCASTER, PA. * * * * * PREFACE. The appearance of the HARVARD PSYCHOLOGICAL STUDIES does not indicate an internal change in the work of the Harvard Psychological Laboratory. But while up to this time the results of our investigations have been scattered in various places, and have often remained unpublished through lack of space, henceforth, we hope to have in these STUDIES the opportunity to publish the researches of the Harvard Laboratory more fully and in one place. Only contributions from members of the Harvard Psychological Laboratory will be printed in these volumes, which will appear at irregular intervals, and the contributions will represent only our experimental work; non-experimental papers will form an exception, as with the present volume, wherein only the last one of the sixteen papers belongs to theoretical psychology.