In Volume II. of the “Essay on the Principle of Population” (edition 1806) there are to be found a number of most interesting remarks on the population question. Book II. contains chapters on the Fruitfulness of Marriage, on the Effects of Epidemics, on Registers of Births, Deaths, and Marriages, and on the General Deductions from the Preceding View of Society. “There is no absolutely necessary connection,” says Malthus, “between the average age of marriage and the average age of death. In a country the resources of which will allow of a rapid increase of population, the expectation of life or the average age of death may be extremely high, and yet the age of marriage may be very early; and the marriages, then, compared with the contemporary deaths of the registers, would, even after the correction for second and third marriages, be very much too great to represent the true proportion of the born living to marry.” At the commencement of this century, it appears from the transactions of the Society of Philadelphia, in a paper by Mr. Barton, entitled “Observations on the Probability of Life in the United States,” that the proportion of marriages to births was as 1 to 4½. As, however, this proportion was taken principally from towns, it is probable, according to Malthus, that the births given were too low, and that as many as five might be taken as an average for town and country. According to this author, the mortality at that date was about 1 in 45; and, if the population doubled in twenty-five years, the births would be 1 in 20 (50 per 1,000). In England at the commencement of this century the proportion of marriages to births appears to have been about 100 to 350. But in those days Mr. Malthus calculated that the annual marriages to the births in England amounted to about 1 in 4. In the East End of London at the present day the writer has found that the average number of children to a marriage among the women of the poorer classes is about 7, whilst the annual births in England and Wales to the marriages are nearly as 4¼ to 1. In France the annual marriages are to the births as 1 to 3. A writer in Mr. Malthus’s day, Crome, observes that when, the marriages of a country yield less than four births, the population is in a very precarious state; and he estimates the prolificness of marriages by the proportion of yearly births to marriages. If this had been true, the population of many countries of Europe would be at present in a precarious state, since in many, as in France, the proportion of marriages to births is much under 4 to 1.