PREFACE 
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A 
I have to express my indebtedness to two of my colleagues, Mr. 
Edwin Frickey and Mr. H. D. White, for most helpful aid and advice 
in revising the manuscript and correcting the proof sheets. The 
Bureau of International Research of Harvard University and Radcliffe 
College, under a grant from the Laura Spelman Memorial Foundation, 
has made appropriations for research on special problems and for 
clerical service which have greatly facilitated my work. I hope that 
the results as here presented will be found to justify the enlightened 
policy of thus aiding scientific research. 
F. W. Taussia