492 On the Fruitf alliens of Marriages. Bk. ii. 



and though rather more than half live to marry, 

 the preventive check might prevail considerably 

 (as we know it does), though not to the same ex- 

 tent as in Norway and Switzerland. 



The preventive check is perhaps best measured 

 by the smallness of the proportion of yearly births 

 to the whole population. The proportion of 

 yearly marriages to the population is only a just 

 criterion in countries similarly circumstanced, but 

 is incorrect where there is a difference in the pro- 

 lifickness of marriages or in the proportion of the 

 population under the age of puberty, and in the 

 rate of increase. If all the marriages of a country, 

 be they few or many, take place young, and be 

 consequently prolific, it is evident that, to produce 

 the same proportion of births, a smaller proportion 

 of marriages will be necessary; or with the same 

 proportion of marriages a greater proportion of 

 births will be produced. This latter case seems 

 to be applicable to France, where both the births 

 and deaths are greater than in Sweden, though 

 the proportion of marriages is nearly the same, or 

 rather less. And when, in two countries com- 

 pared, one of them has a much greater part of its 

 population under the age of puberty than the 

 other, it is evident that any general proportion of 

 the yearly marriages to the whole population will 

 not imply the same operation of the preventive 

 check among those of a marriageable age. 



It is, in part, the small proportion of the popu- 

 lation under the age of puberty, as well as the in- 



