LIST OF DIAGRAMS
| DIAGRAM | PAGE |
| [1.] Average interval before filing petition after attainment of twenty-one years (or time of arrival, if arriving after twenty-one years) for petitioners arriving at ages of one to fourteen, fifteen to twenty, and twenty-one years and over | [242] |
| [2.] Average interval before filing petition after arrival at age twenty-one or over by races. The bars which are in black represent countries from which the subject people constituted almost entirely the immigration to this country | [245] |
INTRODUCTION
It would require a very long list of names to give specific mention of all those who have rendered substantial aid in gathering the information on which this volume is based. The Commissioner of Naturalization, Mr. Richard K. Campbell; the former Director of Citizenship, Mr. Raymond F. Crist, and the chief examiners under their direction, have done all in their power to afford information and other assistance. Several hundred judges of naturalization courts in all parts of the country, took pains to answer our questionnaire and personal letters on special questions. Students of immigration and naturalization problems have been ungrudging in their co-operation.
The tedious and painstaking work of compiling the information contained in more than 26,000 petitions for naturalization, analyzed in the statistical chapters of this book, was done more especially under the direction of Professor Raymond Moley, then at Western Reserve University, Cleveland; Hornell Hart, of Cincinnati; Professor S. C. Kohs, of Reed College, for Portland, Oregon; Professor T. T. Waterman, of the University of the state of Washington, for Seattle, and Professor L. H. Hawkins, of Clark University, for Worcester, Mass. Aside from the service of these volunteer assistants, thanks are due in more than perfunctory manner to the members of the staff of the Americanization Study who devoted long hours to this exacting task.