The terms are in proportion; the product of the two extremes being nearly equal to the products of the means, or the deaths in Winter are to the deaths in Spring, as the deaths in Autumn to those in Summer. The proportion is perceived when no correction has been made in the quarterly deaths registered.

Admitting that this law should continue to prevail, as the proportion is also nearly arithmetical, a very close approximation to the average number of deaths in the whole year may be deduced either from the deaths registered in Spring and Autumn, or in Summer and Winter; thus the average annual deaths in the four years, 1838-41, was 346,252; the deaths in Spring and Autumn were 173,478; and twice that number gives 346,956, only 704 above the yearly average; while the deaths in Winter and Summer, multiplied by 2, give 345,548, or 704 below the annual average.

To exhibit the order in which marriages, births, and deaths take place more evidently, the Registrar-General annexes a summary view of the series of facts, which appear to be governed by the influence of the seasons according to the same law of proportion.

Relative number (corrected for inequality of time) of marriages, births, and deaths, in the seasons of the year

The seasons have most influence on the number of marriages; least on the number of births. If 100 be taken to represent the lowest average number registered in a quarter, the births rise to 108, the marriages to 142, the deaths to 129. According to the abstracts down to the present time, the births and deaths are most numerous in Winter, marriages in Autumn; whilst the smallest number of births and deaths occur in Summer, of marriages in Winter. It is a matter which has been frequently observed, that the marriages and births are most numerous where the mortality is highest.

We were very desirous of presenting to our readers an account of the construction and uses of Life-Tables, as they are called, into the nature and method of which the Registrar-General has entered very fully. Fearing, however, that such details would be rather foreign to the pages of a Journal, whose duty and character it is to be practical, we shall content ourselves with stating some of the more prominent applications of these tables. A Life-Table shows, out of a given number born alive, the numbers living at every year of age, for 100 or 105 years. The assumed number born alive, technically called the base or radix of the table, is arbitrary; and the age at which the table terminates varies in different tables. The yearly deaths are called the " decrements of life." In the Life-Table given in this volume it is assumed that 100,000 form the basis; from the proportion of the two sexes registered, it will be found that 51,274 of them were boys, 48,726 girls. In order to facilitate the understanding of the principle, we will further assume that the 100,000 were all born on the same day-the 1st of Jan. 1841; and that the survivors, counted on the first day of 1842, 1843, and of every year for the next 100 years, will exist in the numbers against the respective ages of the annexed table. Now, on inspecting the table, it will be seen that out of the 100,000 children born on Jan. 1st, 1841, only 85,369 were alive on Jan. 1, 1842; so that 14,631 perished in the first year. Jan. 1, 1843, the survivors were two years old, and in number 80,102; so that 5,267 died in the second year. Jan. 1, 1846, the 5th year of age will be attained, and there will be 74,201 living. So that in the first five years 25,799 of the 100,000 children born, die. During the next five years, the mortality becomes less considerable; and from 10 to 15 the loss of life remains small-68,627 will live to the age of 15. At this age the loss of life among girls is greater than among boys, and it continues so for the next five years. The mortality appears to increase rather rapidly from 12 to 15; and then at a slow regular rate from 15 to 55 years: 66,059 attain the age of 20. It was observed that 51,274 boys were born alive to 48,726 girls; but the mortality in infancy is greater among boys than girls; so that 31,958 males attain the age of 25, and 31,623 females attain the age of 24. This is about the average age of marriage in England; and the number of the two sexes is then nearly equal. About four-fifths of the males who attain the age of manhood marry; the proportion of women who marry being the same. Of the 100,000 persons born, 50,301 attain the age of 45, viz. 25,311 men, and 24,990 women. The chance of living from 25 to 45 is rather in favour of English women. The various hardships, perils, and annoyances to which men are exposed counterbalance the dangers of child-bearing. At the age of 55 a more rapid rate of mortality will set in, and more than a thousand die every year; yet 37,996 will be alive at the age of 60, and 24,531 attain the age of 70-11,823 men, and 12,708 women-the mortality of women being less than that of men after 55:-by the various causes of wear and tear, and more than all, by the natural falling off of vitality, at the age of 80 the numbers will be reduced to 9,398. After the age of 80 the observations grow uncertain; but if we admit their accuracy, 1,140 will attain the age of 90; 16 that of 100; and of the 100,000, one man and one woman-like the lingering barks of an innumerable convoy-will

reach their distant haven in 105 years, and die in 1945. The nature of this calculation may be readily understood. It may have been ascertained that of 100,000 children born in Jan. 1841, 80,102 were alive in Jan. 1843; but we could not, of course, if so disposed, know by direct means how many will live through the year, and see 1844; it was, however, ascertained at the census that there were 437,276 children living in 1841 of the age of 2 and under 3 years; the deaths of 15,027 children of the same age were registered. Hence as 15,027 died to 437,276 living, it is a mere matter of numbers to determine how many die and how many survive a year out of 80,102 children exactly 2 years old. According to the Table, 2,710 die out of 80,102, and 77,392 attain the third birth-day, and will be alive Jan. 1, 1844.

The mortality at certain intervals of age can always be determined from a comparison of the numbers living with the deaths: and from the ascertained mortality the annual survivors can be calculated. Thus in 1841 it was found that 6,633 men died at the age 20-25 out of 724,013 living; the mean age of those persons may be taken to be 22 years: we know the mortality, therefore, at that age, and can tell how many of a given number, say 32,792, aged 22, will live a year-how many of the 100,000 alive on Jan. 1, 1863, will be alive on Jan. 1, 1864.

The Life-Table, in its present form, as given in the volume now under consideration, possesses several remarkable properties. It shows the probability or chance of living a year or any number of years at any age. Thus 100,000 forming the base or radix, and 85,369 being the number living to the end of the first year, at birth the chance of living a year is .85,369, the chance of dying .14,631; for there are 100,000 chances, and 85,369 in favour of living. At the age of 40 the chance of living a year is 53,134 ; for, according to the Table, the number who die in the next year 53,825 is 691, and the number who survive is 53,134; so it is 53,134 to 691, that a person aged 40 will live a year. At 60 the chance of living a year 36,874 -; the denominator of the fraction (37,996) expressing the total 37,996 number of chances, and the numerator (36,874) the chances in favour of 1,122 37,996 36,8741,122 37,996 37,996 37,996

is

living. The chance of dying is

gether

=

and the two fractions added to

1: unity being in the arithmetic

of probabilities the symbol of certainty, the certainty that the person will die or live, is thus expressed.

By inspecting this Table we may readily see the probable duration of life; it is in fact the time in which the number born is reduced one-half; in the English Life-Table this will be found to be 45 years; that is, it is probable that a child will live to 45 years: for, by looking at the Table, it will be seen that the 100,000 are reduced to 50,301-nearly half their number-by the age 45; there is, therefore, nearly an equal number of

chances (50,000) in favour of living to, and of dying before the age 45. The probable life of a boy is 44, of a girl 47 years. Suppose we wish to ascertain how long it is probable that a woman aged 25 will live. On inspecting the table, we see that the survivors out of the 100,000, who have attained their 25th year, are 31,337; the half of this is 15,668, the number surviving at the age of 66; it is probable, therefore, that the woman will live to the age of 66, that is, that she will live for 41 years after her 25th year. Again, suppose we wish to ascertain the age of a man at the age of 60. By inspecting the table we see that the number of survivors at this age, is 18,808; now the half of this is 9,404, to which the 18,808 are seen in the table to be reduced at the age of 73; at 60, therefore, it is probable that a man will yet live 13 years.

Several uses may be made of the Life-Table. It may be readily converted into a population table, shewing the total numbers living, and the numbers living at every age. The uses of the Life-Table in determining the value of life annuities, leases, livings, pensions, &c. are well known. We are almost tempted to present to our readers one or two instances of the method of employing it in such cases, but we apprehend it may lead us from our more legitimate department.

By adding up the column of "LIVING," as given in the English LifeTable now under consideration, the sum of the numbers will be found to amount to 4,165,890; subtract half 100,000 from this, and 4,115,890, the number of the years which the 100,000 persons live, will be obtained. Divide the years of life, 4,115,890, by 100,000, and the quotient, 41.16, will be the mean age, or, as it is sometimes called the expectation of life; for males it is 40 years, females 42, and for both sexes 41 years. By repeating the process, the expectation of life at each year of age is obtained; at five years, it is 50 years; at ten 47; at twenty 40; at thirty 34; at forty 27; at fifty 21; at sixty 14, &c. &c. The average age at which persons aged 30 will die, is 64 years, and 74 is the average age at which sexagenarians will die.

It is observed, that one of the most remarkable points in the comparisons of the expectation of life at different times, in different nations, and various climates, is their singular uniformity. This uniformity does not imply that the external circumstances in which men live have no influence on the duration of life; it only tends to prove that life being regulated by constant laws, the circumstances, adverse or favourable to existence produced, by compensations of various kinds, the same results. The mortality of England varies from year to year; and the mortality of 1841 was rather lower than in previous years; so this table is only given as an approximation to a mean table. We shall now proceed to consider the contents of Mr. Farr's three papers on subjects connected with the Abstracts in the Registrar-General's Annual Report. The first of these papers treats of the construction of Life-Tables. The second presents a general view of the fatal diseases of the year 1841. The third, in continuation of previous papers, is devoted to the examination of the diseases of towns, and their causes. As we have already allotted a considerable portion of space to the subject of Life-Tables, we shall pass on to the second of Mr. Farr's papers, concerning the Public Health. The number of deaths registered in the year 1841 was 343,847, less by 15,714 than

359,561, the number registered in 1840. The mortality was .001,289 less in 1841 than in the previous year. In 1840 out of a million living 22,878 persons died; in 1841 out of the same number living 21,589 died. Of the decrease, 897 in the 1,289 was in the zymotic class of diseases. The idea attached to the term zymotic, Mr. Farr has already explained in his Appendix to the Fourth Report, where he states that he considers a designation like this, as more convenient than the periphrasis "epidemic, endemic, and contagious diseases." It is a property of zymotic diseases to prevail more at one time than at another; to become epidemic, or endemic, or contagious in certain circumstances. The epidemic character of the diseases of this class has been exemplified very remarkably by scarlatina, which raged with increasing severity until 1840, and continued the prevailing epidemic of 1841, though it had begun to decline: 14,161 persons, principally children, died of scarlatina in 1841; and 19,816 had died by this malignant malady in 1840. Measles had been epidemic and destroyed 10,935 lives in 1839; the deaths from measles in 1841 were 6,894. Small-pox was fatal to 16,268 persons in 1838, to 9,131 in 1839, to 10,434 in 1840, and to only 6,368 in 1841. It was less fatal in 1841 than either measles, scarlatina, or hooping-cough. happy result is probably to be ascribed, in a great part, to the Vaccination Act, which came into operation in 1840; and may be expected, by extending the application of Jenner's great discovery, to effect a still further reduction in the sufferings, deformity, and mortality dependent on small-pox.

This

The deaths of 48,053 persons were ascribed to diseases of uncertain or variable seat. Many of the cases of “ hæmorrhage," returned " rupture of a blood-vessel," &c. belong to phthisis, to which head hæmoptysis, or spitting of blood, was referred. Diseases of the respiratory organs were fatal to 92,183 persons in 1841; the mortality which they occasioned was nearly six in 1,000; it was 5,911 in a million, or 132 less than in 1840, when 6,043 in a millon died of pulmonary affections. Of the decrease of 132 to a million 54 was in pneumonia, and 75 in phthisis. The mortality by these two diseases remained, nevertheless, excessively high: thus

The progressive increase in the number of cases registered as heart disease, from 3,319 to 4,246, may be ascribed to the diffusion of new methods of diagnosis, as well as to improvements in the character of the registration.

The deaths by diseases of the digestive organs were 22,398. The mortality was 1,436 in a million, or 29 less than in the previous year.

Deaths by Childbirth.

In 1841, 3,007 mothers died in childbirth. On an average 8 died from