Page:Encyclopædia Britannica, Ninth Edition, v. 19.djvu/537

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On the somewhat anomalous figures we must observe that those relating to and are possibly to be explained by the hypothesis of inaccurate. We may add that, if a distinction is made between and, it is usually found that the excess of   is greater among the. In, therefore, where the proportion of to   is high there will usually be a higher proportion of  to   than in  where there are not relatively so many   (Block, p.429). Interesting inquiries have been made into the facts regarding the distribution of during the, showing that there are, as a rule, more  in some  than in others, and also as to the influence high  for the primary necessaries of life have on the number of  (Mayr, p.235).

The Death-Rate.—The death-rate of a population is the proportion borne by the number of deaths in a to the number of the population. The population is to be reckoned as has been already described in dealing with the birth-rate. This very important quantity is sometimes confused with another relating to the same phenomenon, namely, the mean duration of life. The difficulties in obtaining an accurate death-rate are, if any thing, greater than in the case of the birth-rate.

This table is sufficient for our purpose, which is to give a general idea as to the death-rate of these. Much more accurate approximations are, however, needed for, and very elaborate valuations of the death-rate will be found in G.F. Knapp’s Ueber die Ermittelung der Sterblichkeit. Great pains have been taken by most to obtain accurate figures as to the mortality of the population, and the literature dealing with the subject is of great extent. We must now show how the death-rate is usually composed as regards age. The following table (X.) shows the number of persons out of every hundred deaths who died at the undermentioned in each of the named (Haushofer, p.143; quoted from the Movimento):—

It will be seen that from nearly one-fifth to nearly one-third of the deaths were those of less than twelve old. The very high proportion of deaths at this age in was  made the subject of a special inquiry by, and it was found to be largely due to the bad mode of bringing up  peculiar to certain localities (Mayr, pp.91, 319). The composition of the death-rate in regard to must be touched on briefly. As we have seen, more are  than. Owing, however, to the greater mortality among the their number is rapidly reduced during the first few  of life, so that at any given moment the population is composed as stated in the age scales. The exact mode in which a given number of persons in the same  disappears by death is shown in the elaborate tables of mortality used by. These tables are different for different and for  and. Very elaborate tables of survival were prepared for the in – for calculating.

We cannot here deal with what is known as the “population question.” Any adequate discussion of that highly important subject would involve considerations outside the limits of this article. The “population question” is a question of, while the present article seeks only to point out certain well-ascertained facts regarding the phenomenon of superorganic called population. The facts in question are general, and, though sufficient to indicate the nature of the phenomenon, and the broad divisions which are most convenient for its further investigation, are quite insufficient as the basis for the formation of any regarding the actions of the individuals composing the population.

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