A treatise on man and the development of his faculties / by A. Quetelet ; now first translated into English.
- Date:
- 1842
Licence: Public Domain Mark
Credit: A treatise on man and the development of his faculties / by A. Quetelet ; now first translated into English. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
26/158 (page 14)
![u uerully bappoii3 througliout Europe, Hint men, wliuu they marry, arc live or six years older than women, BO that the preponderance of nude births will be ulmost the same, as is established by the researches Of Hofaeker and Sadler, -who give, as the ratio of births of both sexes, the number 103'.'5 nearly, when the lather is from 1 to 6 years older than the mother. Now, we think that this ratio will be larger or smaller, according as the difference of age of the parents is greater or less in the different nations, in town or country, among the persons whose connexions are legitimate or illegithnatc; and, lastly, according to all the circumstances W'liich may cause the ages to vary at which production takes place; so that the age of the i)arents will be the principal regulator ■which determines the magnitude of the ratio between the births ot the two sexes. Hence we see how impor- tant it is to du'ect om’ researches to the age at which tnaj-riage takes place, especially since the greater or less mortality of children depends on these ages.* 2. Influence of Age on the Feeundity of Marriages. Wc have just seen that the relative age of the parties exercises a sensible influence on the ratio of male births : it is natural to suppose, that it will have stUl more influence with regard to the number of births, or the fecundity. I am not acquainted with much on this subject besides the researches of lilr Sadler, which were imdertaken ivith the design of showing that the age of parents, considered apart, has no influence on the ratio of male to female bu'ths. I have introduced them above, taking care to calcu- late the mmiber expressing the fecimdity in the last column. However, since the numbers of Mr Sadler are generally small, I have thought proper to receive fewer divisions of ages, which ivill give a greater pro- bability to my particular results : we may sum up all these results in the foUo'wing table:— According to the Registers of English Couples. Number of Childi-en procreated by one Individual; being at tlie time of Mai’riage— Under 26 years. Between 26 and 36. Moro than 36 years. Husbands, 6'H 4'43 2-34 AVives, .5-13 3-49 2-89 Widowers & Widows, n-oo t 4\50 3-(!6 We see that the fecundity of marriages, all things being equal, climhiishes in proi^ortiou to the increas- * [Assuming as a fact, an assertion wliicli has been often made, that thoughtless and premature mai-riages, that is, when both sexes are very yoimg, take place to a much greater extent in Ireland than in most other countries, records of such marriages would go far to solvo the difficult question proposed above by M. Quetelet: such records, if they exist, might be compared with those of Holland, where it is presumed that a moral condition of the people exists, which is the antithesis to the Irish character. A comparison of these records with each other would go far to solve tho question. Should it be found that the male se.x stiU predominates in births in Ireland, it would then be clear th.at the theory of age proposed by M. Buzareignes, and supported by M. Quetelet, would be at fault, whilst tliat of Bickes, or the theory of race, which is the view supi)Orted by tho translator, would be tho true one. It is quite possible, however, that both causes may have their influence; but a glance at tho table, page 12, proves indisputably, as far as such records go, that, commencing in Eastern Europe with tho Sclavonic race, amongst whom we find the dispropor- tion of boys to girls greatest, and passing through tho mixed Sclavonic and Saxon races of Prussia, and through the Celtic nations of France and the north of Italy, to 'Westphalia, Great Britain, and Sweden, where the S.-ixon race exists in its greatest purity, we find tho disproportion between boys and girls constantly decreasing, and arc entitled, tfiereforo, to conclude, that whatever other causes may bo in operation, blood or race comes in for at least a considerable share in the eficcts.] t This number being founded on five marriages only, which produced 41 children, cannot bo entitled to much conlidcncc. ing age of tlie parties. To observe the influence of age itself on the fecundity of individuals, it would be necessary to compute the probability of life in mar- rying; for it is very evident that he who has yet twice as long to live as another person, may hope, all j things being equal, to procreate more children. It is ’ very true, on the other hand, that those who marry ■ young have some fear lest they should have too 1 numerous a family; which is not the case when jier- sons marry at a more advanced age. In supposing, i as a kind of limit, that, all things being equal, the j fecundity depends on the probability of life, it would be necessary for each age to divide each of the ratios , previously found by the corresponding number which expresses the length of the probable life. Now, in ( admitting approximatively 36, 32, and 21 years, as I the probability of life of the individuals of the first class; afterwards, for the women, 40, 34, and 23 years; and, lastly, for tho widows, 38, 33, and 22 years, we shall have, as the relative values of fecundity— According to tho Registers of English Couples. Number of Children procreated by one Individual; being at tho time of ^Marriage— Under 26 years. Between 26 and 36. More than 36 years. Husbands, 0-142 0-130 0-135 Wives, 0-126 0 103 0-12.5 AVidowers & Widows, 0131 o-i;ic O-IGG These numbers, which only express the relative ■ fecundit}'', serve, moreover, to show that the greatest ■ altitude for reproduction is evidentlj', among the in- dividuals whom we are considering, before the age of 26 years; moreover, we see that it is not sensibly diminished in men until the 36th year. The data for females are too few to be relied on, since they only include nine women more than 36 years of age. When we consider the respective ages of the hus- bands, we fmd, still availing ourselves of the numbers furnished by Mr Sadler, and which we have quoted above, that the fecundity of marriages reaches its , greatest value when the ages of the married persons ‘j are the same, or when the man is from 1 to 6 years j older than the woman : it does not sensibly diminish, if the difference of age does not exceed 16 years; but ' when it is greater, or when the man is younger than , the woman, the fecundity seems to be at its mini/num. These axe results which it is .in some measure easy to ^ foresee. Moreover, I only proposed to point out these researches, ivithout pretending to go deeply into them, o since adequate data are stiU. wanting. Mr Sadler, in another part of his work, has ascer- tained the number of children produced by the wives 1 of those couples in England whose ages at the time I of marriage he has been able to determine: putting ■ down all the marriages this time, whether they^ were a fruitful or not, or were born during the first or second. I time of wedlock; and these arc his results:— 1 Age at tlie time of Marriage. Number of Marriages. Number of Children. Mortality of Children he- fore the Mar- riageable Age. Births by Marriage. Deaths i for ono ^ Birth. 12 to l.’i. 32 141 40 4-40 0-283 - l(i to 19, 172 797 166 Ai)3 0-203 20 to 2;i, 198 uun 195 .5-21 0-188 24 to 27, 86 467 180 5-43 0-I7I We see here that, from 12 to 27 years, the fecun- X dity of women continues to increase. At first view, »X this result a])i)ears contrary to those which have been i previously obtained; but it is proper to observe, that ■ he is considering marriages in ^'iieral, and not, as we B have previously supposed, fruitful inarriiigcs in par- B ticular. We have seen that, on tliis latter hypothesis, B the fecimdity of women docs not perceptibly vary B under the age of 26 years. We can then only attri- M](https://iiif.wellcomecollection.org/image/b21987257_0026.jp2/full/800%2C/0/default.jpg)
