LAWS OF THE FERTILITY OF WOMEN. 307 



his conclusions, but I cannot in his work discover any satisfactory grounds for 

 them. 



Before passing from the perseverance in fertility of the early married, I will 

 point out a difficulty of which it gives the solution. In my former paper, read to 

 this Society, I showed that initial fecundity in wives from 15 to 19 years of age, 

 is far less than at any age from 20 to 34 ; that is, of the young women very 

 much fewer have children within two years ; at the same time, I showed that 

 the fecundity of the mass of wives in our population is greatest at the commence- 

 ment of the child-bearing period of life, and after that epoch gradually diminishes ; 

 that is, those not the most fecund do, as a mass, produce most children. These 

 two propositions are, at first sight, difficult to reconcile ; and it is accordingly 

 satisfactory to be able to show that the greater continuance in fertility of the 

 mass of younger wives is the explanation of the apparent anomaly. To illustrate 

 how the Tables read, in affording this explanation, I may state, that while I 

 formerly showed that the wives from 15 to 19 years of age are not so fecund as 

 those from 20 to 24 years of age, the Tables last adduced show that at the 5th 

 year of marriage, the youngest married — that is, at ages from 15 to 19 — already 

 surpass all others in fertility, 1 in 26 bearing; that at the 10th year of marriage 

 they still further surpass in fertility all others, 1 in 3-2 bearing ; and that at the 

 15th year of marriage, they in a still higher degree surpass all others, 1 in every 

 46 bearing children, within a year. 



Finally, under this head, I notice an important element of the inexactness 

 that enters into the data here used, namely, the occurrence of second and third 

 marriages. But the influence of this element is almost certainly inconsiderable 

 for the following reasons: — In cases of second and subsequent marriages, the 

 data used are exclusively those of the last marriage; as far as is known, a 

 woman's previous marriage does not interfere with her subsequent fertility ; it is 

 shown in this paper, that a woman's previous fertility tends to ensure continuance 

 in fertility ; it will be shown that a woman's previous fertility tends to diminish 

 the intensity of her subsequent fertility, when that is compared with the fertility 

 of women late in being married and having family ; and the admixture of second 

 and subsequent marriages in the data which include only the last marriage, 

 would tend to diminish the force of the results, as bearing out these con- 

 clusions. They are therefore all the more secure, from the fact of the inter- 

 mingling of some data which would diminish their apparent influence. 



Another inconsiderable element of inexactness I shall only mention, the 

 occurrence of twins, and both being counted in the figures. 



Chapter X. — Fertility of Persistently Fertile Wives of different Ages. 



I may here repeat that, by persistently fertile, I mean fertile up till the time 

 of the collection of the data. And I adduce a Table which clearly shows, so far 



VOL. XXIV. PART II. 4 O 



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