INCREASE OF THE BIRTH-RATE OF THE SUPERIOR
Imagine 200 babies born to parents of native stock in the United States. On the average, 103 of them will be boys and 97 girls. By the time the girls reach a marriageable age (say 20 years), at least 19 will have died, leaving 78 possible wives, on whom the duty of perpetuating that section of the race depends.
We said "Possible" wives, not probable; for not all will marry. It is difficult to say just how many will become wives, but Robert J. Sprague has reported on several investigations that illuminate the point.
In a selected New England village in 1890, he says, "there were forty marriageable girls between the ages of 20 and 35. To-day thirty-two of these are married, 20 per cent. are spinsters.
"An investigation of 260 families of the Massachusetts Agricultural College students shows that out of 832 women over 40 years of age 755 or