In estimating the death-rates of different sanitary areas of London it has been customary for the last six years to distribute the deaths occurring in institutions to the districts to which the deceased 'belonged,' and to exclude entirely the deaths of persons belonging to districts outside registration London; in this way about 1·5 per cent. of the deaths occurring in registration London may be excluded. This manœuvre helps to diminish the London death-rate, but, as no account is taken of sick people who leave London to die elsewhere, it is manifestly an unjustifiable thing to do. If the strangers who die in London institutions are to be excluded, it is a question whether all strangers merely sojourning in London ought not to be excluded from the estimate of population. Again, a man comes from the country and is knocked down by a vehicle in the street and dies in a London hospital; or during a sojourn in London he gets caught in a London fog and dies of bronchitis; or he 'catches' influenza, or pneumonia, or diphtheria in London and dies. Surely the deaths of these three ought to be credited to London in all fairness. It is a very dangerous thing to 'cook' statistics, and we do not get much nearer the truth by doing so. The best indication, probably, as to whether the conditions of life in any locality are healthy or the reverse is the infant mortality; in this way we exclude the fallacies due to abnormal age distribution, because we compare identical age periods; and the proportion of the sexes among children is practically the same everywhere. We exclude also the influences of occupation. By studying the mortality of children under five we are studying the influence of the home and home surroundings on the incidence of disease, which is particularly what we wish to do. In the decennial supplement of the Registrar-General published in 1896, Dr. Tatham gives a table (Table II. p. lxxxii. _et seq._) of the 'annual death-rate per million living among children under five years of age, from all causes and from several causes, 1881-90.' This valuable table ought to be most widely studied. Being based upon statistics of ten years intervening between the censuses of 1881 and 1891, the estimates of population have a maximum of reliability, because we are relieved of the errors inseparable from statistics referring only to short periods of time. It is constantly stated that London is the healthiest city in the world, a statement which, if true, must make us very sorry for the other cities. In Dr. Tatham's table, alluded to above, he first deals with counties. We find that the death-rate of children under five from all causes in England was 56,825 per million; that the highest death-rate among children was in Lancashire (72,795), and the next highest was in the county of London (68,164). The lowest death-rate was in the county of Dorset (35,651). Table Legend: