This book is an introduction to demography, the scientific study of popuiation. In it I have attempted to summarize what is known about the subject of population and to describe the methods and techniques by which that knowledge has been attained. The volume is therefore concerned with sources of data and methodology fully as much as with known facts about, and relationships among, demographic phenomena. The attempt has been made to treat the subjects in language that can be readily understood by the advanced undergraduate in college or university.
The bulk of the data pertains to the United States, since these data are most readily available and because the American student is most concerned with materials about his own country. However, no effort has been spared to assemble comparable information from other portions of the world so that the situation in the United States may be compared with, or contrasted to, that in other great world regions. Naturally the reports of the various censuses taken in this country, from the first to the sixteenth, are the sources of many of the facts. Together these reports form the world's greatest repository of demographic information. Any student of the social sciences would be well paid for taking a semester's work in population even though the course did no more than familiarize him with the reports of the decennial census and the annual publications on vital statistics. The value of the primary materials gathered by the Bureau of the Census has been greatly enhanced by the excellent analytical efforts on the part of demographers during the last quarter of a century. It can rightfully be said that population study is among the most rapidly advancing parts of social science.
A word is necessary about the title, since general books in this field ordinarily are labeled "Population Problems." The avoidance of the pathological emphasis is deliberate. I do not subscribe to the proposition that the United States has been, or is in any immediate danger of being, overpopulated. As far as I am able to judge, mankind is not at the crossroads from the demographic standpoint; nor are we in the United States in any danger of having to hang out the sign "Standing Room Only." Our science has progressed to the point that one can well afford to play down the pathological and to refrain from efforts at sensationalism, once thought . . .