OCR Rendition - approximate

268 REPORT-1883. a a 1 V i I e I s X t t t 0 r 3 a S t a a r it REPORT OF TILE ANTIIROPOMETRIC COMMIT'T'EE. 289' at a rate similar to that of. t;he weight ; more slowly and regularly up to 30 years, after which it declines at an increasing rate to the age of 60 years. The strength of females increases at a more uniform rate from ft to It) years, more slowly to 30, after which it falls off in a manner similar to that of males. The curves of strength for the two sexes are not parallel at 11 years females are weaker than males by 22 lbs., at 20~ years of age by 36 lbs. The Period of Malurily. in Man. 61. The Tables do not show distinctly at what period man attains his full stature, and much difference of opinion exists on this subject. Some French writers (Barnard, Allaire, &c.) maintain that growth in height goes on until the 32nd or 3::ith year, and Dr. Baxter arrives at the same conclusion from the statistics of the United States Army ; while most English writers (Danson, Aitken, Roberts, &c.) regard the 25th as the year of mature growth, and Dr. Beddoe places it as early as thu 23rd year, admitting, however, that a slight increase may take place after this age. The difference of opinion on this subject arises, no doubt, from the faulty method of relying on the measurcrnents of many diilbrent individuals, instead of measuring the same individuals from year to year until growth ceases. The elimination of the weak and ill-developed by death, the difficulty of following the same class, and all the members of the class, through successive years, and the selection of special classes (i.e. recruits whose ages are never certain), invalidate all conclusions as to the period of maturity drawn from statistics of measurements of many different persons ; but, allowing for these sources of error, and judging by the run of the curves formed by the means and averages, it is probable that little actual growth takes place after the age of 21, and that it entirely ceases by the 25th year. It is evident, moreover, from Table XVI., that the full stature is attained earlier in the well-fed and most favoured class (Class I.) than in the ill-fed and least favoured classes of the community (Class IV.). 62. It is difficult to understand, moreover, how any increase of stature can take place after the bones of the skeleton have become consolidated, and the epiphyses firmly united to the body of their respective bones ; and the last of these unions in the long bones, on which the stature depends, occurs about the 23rd year. In adopting the 23rd year for men and the 20th for women as the ages of the attainment of maturity the committee was influenced by these considerations, and a desire to understate rather than overstate its case, and to embrace as large a number of observations as possible in its tables. In inquiries of this kind there is generally a slight amount of unconscious selection, very small persons being passed over, or having objections to being measured; and any deficiency of this kind will be balanced by the loss of growth which may occur after the age of 23 years. Females attain to maturity earlier than males, and the age of full growth has been fixed three years earlier for them. Influence of Advivnci-rvy Ayr. 63. Thomaintenanco of the stature throughout life as shown by Table XVI. is a new and unexpected fact, but it is probably due to the survival of the taller and better developed members of the population, and the elimination by disease or death of the smaller and feebler ones. Quetelet 18t~3. u