March 1, 1918] 



SCIENCE 



203 



increased only two million, while Germany 

 in the same period almost doubled in popu- 

 lation. In 1811, the population of France 

 constituted 16 per cent, of all Europe. 

 One hundred years later the French popu- 

 lation constituted onlj- 9 per cent, of the 

 total. 



This situation for France may be ac- 

 counted for principally in terms of its de- 

 clining birth rate. Such figures as I have 

 for France show that at about 1830 the rate 

 was 30 birtlis per 1,000 of population.* The 

 last available figure for 1914 was 18 per 

 1,000; the death rate was 19.6 per 1.000.= 

 This was the first war j'ear, but already in 

 1911 the death rate, 19.6, exceeded the 

 birth rate, 18.7. The reduction of more 

 than one third in the birth rate during the 

 eighty years was both gradual and continu- 

 ous. On the other hand, the birth rates in 

 the German Empire and in the United 

 Kingdom continued high, over 30 per 

 1,000 up to 1895 in the latter and up to 

 1909 in the former. Since then the birth 

 rates have declined rapidly in both coun- 

 tries, but the enormous increases in popu- 

 lation for both Germany and the United 

 Kingdom were achieved before the changes 

 in the birth rate began to make themselves 

 seriously felt. 



We are not concerned entirely with gross 

 totals of population. Equally significant 

 is the internal structure of population. As 

 we shall see later, changes in the constitu- 

 tion of a population almost invariably ap- 

 pear with changes in the birth rate. This 

 will become clearer by comparing the ages 

 below which, one quarter, one half and 

 three quarters of the total populations of 



* ' ' Ministere du Travail et de la Prevoyance So- 

 ciale, " Statistique Internationale du Mouvement 

 de le Population jusqu'en 1905, Vol. 1, 1907. 



5 Annual Beport of the Registrar-General of 

 Births, Deaths and Marriages in England and 

 Wales, 1915, p. 71. 



Germany, of England and Wales and of 

 France, respectively, are found." Thus, 

 one quarter of the population of Germany 

 is under age eleven, one quarter of the pop- 

 ulation of England and Wales is under 

 twelve j'ears of age, whereas one quarter of 

 the French population is under fourteen 

 years. Again, one half of the population 

 of Germany is found under 23.5 years, one 

 half of the population of England and 

 Wales is below twenty-six years while one 

 half of the French population is below age 

 thirty. We find, finally, that three quar- 

 ters of the population of Germany is below 

 age forty-one years, of England and Wales 

 is below forty-two years and of France is 

 below forty-nine years. These figures show 

 clearly that the average age of the French 

 population is considerably higher than 

 that of the other two countries. Its youth 

 and its strength form a smaller part of its 

 total population, while its old and its de- 

 pendents form a much larger part. This 

 we shall find is an invariable consequence 

 of a decreasing birth rate, which reduces 

 the proportion of the young and thus 

 brings into relief an undue proportion of 

 the aged. 



The declining national birth rate of 

 France is also severely selective in charac- 

 ter. The reduction of the birth rate has 

 affected mostly those who are both econom- 

 icall}' and socially best fitted to bear and 

 to raise a family to maturity. A careful 

 classification by Bertillon' of the number 

 of children per 100 families in Paris, shows 

 that the verj' poor have the largest number 

 and the very rich the smallest number of 

 children. The order of size of the family 

 is invariably the reverse of the order of 

 economic condition. Since economic status 



Burn, Joseph, op. cit., p. 30. 



' Bertillon, Jacques, "Nombre d'Enfants par 

 Families," Journal de la Sociiti de Statistique de 

 Paris, AprU, 1901, p. 134. 



