Ch. xi. On the Fruitf ulness of Marriages. 483 



population. This practice would naturally occa- 

 sion a more than usual number of second and 

 third marriages, and of course more than usually 

 increase the proportion of marriages to births in 

 the registers. 



In the Transactions of the Society at Philadel- 

 phia (vol. iii. No. vii. p. 25,) there is a paper by 

 Mr. Barton, entitled Observations on the Probabi- 

 lity of Life in the United States, in which it appears, 

 that the proportion of marriages to births is as 1 

 to &f He mentions indeed 6-*-, but his numbers 

 give only 4^. As however this proportion was 

 taken principally from towns, it is probable that 

 the births are given too low ; and I think we may 

 very safely take as many as five for the average 

 of towns and country. According to the same 

 authority the mortality is about 1 in 45 ; and if 

 the population doubles every 25 years, the births 

 would be about 1 in 20. The proportion of mar- 

 riages to deaths would on these suppositions be 

 as 1 to 2f ; and, corrected for second and third 

 marriages, as 1 to 2*7 nearly. But we cannot 

 suppose, that out of 27 births 20 should live to 

 marry. If however the age of marriage be ten 

 years earlier than the mean age of death, which 

 is highly probable, we must compare the mar- 

 riages of the present year with the deaths ten 

 years later, in order to obtain the true proportion 

 of the born which lives to marry. According to 

 the progress of population here stated, the increase 

 of the deaths in ten years would be a little above 

 •3, and the result will be, that 200 out of 351, or 



i i 2 



