On the fruitfulness of marriages.

would be a rare one, the distance between marriage and death would be the same as between birth and marriage.

If we apply these observations to registers in general, though we shall seldom be able to obtain accurately the true proportion of the born living to marry, on account of our not knowing the average age of marriage, yet we may draw many useful inferences from the information which they contain, and reconcile many of the difficulties with which they are accompanied; and it will generally be found, that in those countries where the marriages bear a very large proportion to the deaths, we shall see reason to believe that the age of marriage is much earlier than the average age of death.

In the Russian table for the year 1799, produced by Mr. Tooke, and referred to p. 372, the proportion of marriages to deaths appeared to be as 100 to 200. When corrected for second and third marriages, by subtracting one sixth from the marriages it will be as 100 to 252. From which it would seem to follow that out of 252 births 200 of them had lived to marry; but we can scarcely conceive any country to be so healthy, as that 200 out of 252 should live to marry. If however we suppose what seems to be probable,

On the fruitfulness of marriages.

that the age of marriage in Russia is 15 years earlier than the expectation of life or the average age of death, then, in order to find the proportion which lives to marry, we must compare the marriages of the present year, with the deaths 15 years later. Supposing the births to deaths to be (as stated p. 372) 183 to 100, and the mortality 1 in 50, the yearly increase will be about of the population; and consequently in 15 years the deaths will have increased a little above .28; and the result will be, that the marriages compared with the deaths 15 years later, will be as 100 to 322. Out of 322 births it will appear that 200 live to marry, which from the known healthiness of children in Russia, and the early age of marriage, is not an improbable proportion. The proportion of marriages to births, being as 100 to 385, the prolificness of marriages, according to the rule laid down, will be as 100 to 411, or each marriage will on an average, including second and third marriages, produce 4.11 births.

The lists given in the earlier part of the chapter on Russia are probably not correct. It is suspect. ed with reason, that there are considerable omissions both in the births and deaths, but particular. ly in the deaths, and consequently the proportion

On the fruitfulness of marriages.

of marriages is given too great. There may also be a further reason for this large proportion of marriages in Russia. The empress Catherine, in her instructions for a new code of laws, notices a custom prevalent among the 'peasants, of of parents obliging their sons, while actually children, to marry full grown women in order to save the expense of buying female slaves. These women, it is said, generally become the mistresses of the father, and the custom is particularly reprobated by the empress as prejudicial to population. This practice would naturally occasion 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 Philadelphia, (vol. iii. No. vii. p. 25) there is a paper by Mr. Barton, entitled Observations on the probability of life in the United States, in which it appears that the proportion of marriages to births is as 1 to 4. He mentions indeed 61, but his numbers give only 41. 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 au

On the fruitfulness of marriages.

thority, 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 2; 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 marriages 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 popula tion 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 about 20 out of 35, instead of 20 out of 27 will live to marry.

The

1 If the proportions mentioned by Mr. Barton be just, the expectation of life in America is considerably less. than in Russia, which is the reason that I have taken only 10 years for the difference between the age of marriage and the age of death, instead of 15 years, as in Russia. According to the mode adopted by Dr. Price, (vol. i. p. 272.) of estimating the expectation of life in countries the po pulation of which is increasing, this expectation in Russia would be about 38, (births, deaths, mean,) and supposing the age of marriage to be 23, the difference would be 15.

On the fruitfulness of marriages.

marriages compared with the births 4 years later, according to the rule laid down, will in this case give 5.58 for the prolificness of marriages. The calculations of Mr. Barton respecting the age to which half of the born live cannot possibly be applicable to America in general. The registers on which they are founded are taken from Philadelphia, and one or two small towns and villages, which do not appear to be so healthy as the moderate towns of Europe, and therefore can form no criterion for the country in general.

In England the average proportion of marriages to births appears of late years to have been about 100 to 350. If we add to the births, instead of, which in the chapter on the Checks to Population in England I conjectured might be nearly the amount of the omissions in the births and deaths, this will allow for the circumstance of illegitimate births; and the marriages will then be to the births as 1 to 4, to the deaths as 1 to 3. Corrected for second and third marriages, the

In America the expectation of life would, upon the same principles, be only 32, (births, deaths, mean. 321) and supposing the age of marriage 223 the difference would be 10.