What are the economic, moral, political and social consequences of the re-distribution of population? What is to be the attitude of the publicist, the statesman, the teacher toward the movement?
These are some of the questions to be answered, so far as may be, in the course of the present investigation. They are not questions capable of off-hand answers, for they are parts of a great problem. As Mackenzie says, "the growth of large cities constitutes perhaps the greatest of all the problems of modern civilization."[1] It is the problem of dwindling district schools, of city labor disputes, of the tenement house, of municipal transit, of agrarian reforms, of the "destitute" country village, of the "submerged tenth" and the physical wastes of civilization,—in short, it touches or underlies most of the practical questions of the day. "The social problem that confronts practical people is in a very great degree the problem of the city."[2] It is, therefore, of prime importance to ascertain the extent of the movement and its probable direction in the future; the forces that may be presumed to cause it; the more immediate as well as the ultimate consequences; and the possible remedies.
To a certain extent the distribution of the inhabitants of the earth is determined by man's physical environment.[3] Nature's mandate it is that explains why the arctic have fewer inhabitants than the temperate zones, why mountainous regions are not so densely settled as valleys. To study the distribution of population, geographers and statisticians calculate the density of population, the number of inhabitants to the square mile or acre, and then compare variations in density with variations in climate, soil, earth formation,
