The method in which the mortality in childhood varies from age to age is a matter of very considerable interest. With each increase of unhygienic circumstances the death-rate among infants is well known to rise and it is commonly taken as a criterion of the measure of the unheathiness of the environment. In a rough way this is quite true but it is not the only criterion, any year of life might equally well be taken. The investigation in this note is based on a tabulation mande from the data published by the Registrar-General of England for the decade 1891–1900. In order tp make the statistics as homogeneous as possible the registration districts have been grouped accroding to the infantile mortalites, intervals of ten being taken in the unit. Thus those districts with death-rates between 80 and 90 have had their populations and deaths grouped togeather, those between 90 and 100 likewise and so on.