Page:Popular Science Monthly Volume 63.djvu/182

178 of the eighteenth century, when the decline began, and at the same time I published complete statistical data for the end of the nineteenth century, when the lowest level had been reached.

I have shown that a gradual decline had already taken place during the colonial period from 6 and more children in the seventeenth century to 4.5 at the end of the eighteenth; then 2 at the close of the nineteenth; data for the intervening period I had none. It seemed reasonable to conjecture a gradual decline with developing civilization and rapidly increasing luxury of life, but proofs were wanting.

The Yale records fill the gap, and supply the intervening data I had so far persistently but vainly searched for; they distinctly portray the gradual decrease in the rate of child-birth and enable me to complete the table, period by period, which shows the remarkable changes that have taken place in family life in this country. To this the highly educated portion of our population is no exception. The decline is general, not confined to any one element, it is the same for college graduate and laboring class, for all American-born, for highly educated and less highly educated, so that higher education can not be the causative factor.

This table presents a startling record for a young and vigorous community, and it is but natural that we should ask for the cause of this rapid decline in birth rate among all classes of the American-born: where are we to seek the explanation? It can not be in physical inability, though the ravages of venereal disease are leaving their traces more clearly with increasing civilization and centralization, and constantly add to the number of the sterile. (This is 2.5 per cent, among a simple, hard-working people in the interior of Russia (Kaluga), and in Norway, whilst 20 and 25 per cent, of marriages are barren in the civilized and infected communities of the United States and of France.) I find 25 and 30 per cent, of families barren among the married graduates of large and centrally located colleges, as low as 9 per cent, in a Princeton class with high marriage rate and large families, an exceptionally healthy condition when we remember that 20 per cent, of all native marriages in the entire state of Massachusetts are childless.

The cause for this decline in family size can not be sought in the increased age for marriage, as this is delayed for all educated and professional men in this country as in England by nearly three years, from 27.2 to 30 for the male, and for the educated female from 24.3 to