----------------------------- GROUP I. GROUP II. Ages. 1838–1854. 1871–1880. ----------------------------- 0 39·91 41·35 5 49·71 50·87 10 47·05 47·60 15 43·18 43·41 20 39·48 39·40 25 36·12 35·68 30 32·76 32·10 35 29·40 28·64 40 26·06 25·30 45 22·76 22·07 50 19·54 18·93 55 16·45 15·95 60 13·53 13·14 65 10·82 10·55 70 8·45 8·27 75 6·49 6·34 80 4·93 4·79 85 3·73 3·56 90 2·84 2·06 95 2·17 2·01 100 1·68 1·61 ----------------------------- _Physical Degeneration of the Race already indicated._ It seems improbable that the short expectancy of middle age can be due to modern overstrain, for external conditions are on the whole improving, and the same fact may be observed in the expectancy of women, who certainly have not been placed under more unfavourable external conditions. Calculations from other periods of years would be here of great value, in order further to eliminate the effects of climatic changes, etc., and it must be remembered that the figures which are the basis of all statistics are only approximate to, and never exactly represent, the true condition of things. For these reasons, it seems important to pursue statistical investigations still further, and to examine the returns of other nations in order to determine whether or no their facts are similar to ours. In the meantime, we may view, and not without inquietude, the probability that our statistics, as far as they go, indicate that racial deterioration has already begun as a sequence to that care for the individual which has characterised the efforts of modern society. The biologist, from quite another group of facts, has independently arrived at conclusions which render this view in the highest degree probable. FOOTNOTES [12] Billing’s “Text-book of the Theory and Practice of Medicine,” p. 8. [13] Report of Leprosy Commission in India, 1890–1. [14] “Bacteria and other Products,” p. 230. [15] “Introduction to Modern Therapeutics” (1892), p. 15. [16] “Natural Inheritance,” p. 182. CHAPTER IV. INSANITY AND ALCOHOLISM. _Nerve Derangements--Insanity._