The most interesting general account of the beginnings of life and the ancestry of man is that given in H. G. Wells’ _Outline of History_, Vol. I, pp. 3-103. A brief summary of the evidence on which the doctrine of evolution rests may be conveniently found in H. R. Burch and S. H. Patterson, American Social Problems, pp. 12-32. Footnote 4: For a discussion of these other factors see Vernon Kellogg, _Darwinism Today_. Footnote 5: There has been much discussion among scientists as to whether acquired characteristics can be transmitted at all. The best opinion seems to be against such transmission, but some biologists still hold to the belief that transmission is possible, particularly in the lower organisms. For a further discussion see W. E. Castle, _Genetics and Eugenics_, pp. 26-27. Footnote 6: One of the best things ever written is the chapter on “Habit” in William James’s _Psychology_. No one will regret the time spent in reading it. CHAPTER II THE PEOPLE, RACES, AND RACIAL PROBLEMS OF THE UNITED STATES _The purpose of this chapter is to explain how the population of the United States has grown, how it is distributed, the varied races of which it is composed, and the racial problems which immigration has created._ [Sidenote: How the national population has grown.] =We, the People of the United States.=—The national constitution begins with the words: “We, the People of the United States”. But who are the people? No one cares to carry a lot of figures in his head and most people think that statistics are uninteresting; but there are some figures which everyone ought to know and, moreover, there are some statistics which are far from being dry or tedious. The figures relating to the population of the United States, its growth and distribution, are interesting because they portray something that the world has never seen before and probably will never see again,—a country doubling its population four times in just about a single century. That is what the United States did in the hundred years from 1790 to 1890. In 1790 the entire population was less than four millions. (There are more people in the single city of New York today, and almost as many in Chicago.) The population had doubled in 1813, and had doubled again in 1838, when it passed sixteen million. In 1864, only twenty-four years later, it had doubled once more (32,000,000). It passed the sixty-four million mark in 1891, and in all probability will double for the fifth time about the year 1940. In 1920, when the last national census was taken the population had passed 105,000,000. [Sidenote: Will this increase continue? If so, with what results?]