Ch. ix. in England (continued). 429 



The assumed omissions therefore in the births 

 and burials seem to answer so far very well. 



It remains to see whether the same supposi- 

 tions will give such a proportion of births to 

 deaths, with such a rate of mortality, as will also 

 account for an increase of numbers in ten years 

 from 9,287,000 to 10,488,000. 



If we divide the population of 1810 by the 

 average births of the preceding five years, with 

 the addition of one-6th, it will appear that the 

 proportion of births to the population is as 1 to 30. 

 But it is obvious that if the population be in- 

 creasing with some rapidity, the average of births 

 for five years, compared with the population at 

 the end of such period, must give the proportion 

 of births too small. And further, there is always 

 a probability that a proportion which is correct 

 for five years may not be correct for ten years. 

 In order to obtain the true proportion applicable 

 to the progress of population during the period 

 in question, we must compare the annual average 

 of the births for the whole term, with the average 

 or mean population of the whole term. 



The whole number of births, with the addition 

 of i, is, as before stated, 3,358,723, and the annual 

 average during the ten years 335,872. The mean 

 population, or the mean between 10,488,000 (the 

 population of 1810) and 9,287,000 (the corrected 

 population of 1800) is 9,887,000; and the latter 



to 1810; but as the registers for this period seem to prove it, I 

 have made my calculations accordingly. 



