Stntintirnl fnvfntigntionti 343 



or a total loss of 5.'?;3 Huriiami's. Here the population increases since 



is greater than unity. As l)efore the extinction rate is quick to begin with 

 but soon slackens clown, as the number of pei-sons holding each surname 

 increases, while the number of surnames diminishes. On the above hypo- 

 thesis nearly a (juartor of newly-created peerages would Ijecome extinct in 

 the first generatioti and half of them by the sixth generation. With any such 

 hyjiothesis there is no need to appeal to sterility as rendering rapidly extinct 

 a large proportion of the peerage.s created for ability. It will be clear that 

 if we take not the number of sons, but the number of children, in computing 

 tlie t'n, the problem becomes that of the extinction of definite stirps; it is 

 highly probable that families die out in approximately the same maimer as 

 they die out in the male line. If mankind has not sprung from a single 

 pair, it seems possible that even the most innnerous nation mav tend with the 

 ages to be the product of a very few stirps, if not of a single pan-. The fable of 

 Adam and Eve may be somewhat truer for an old world tlian for a young one! 

 Beside the data noted in the paper on the stature of boys from urban 

 and rural achools", several .schools j)rovide<l material of a more extended 

 kind, notably Marlborough School, which had e.stal)lished something like an 

 anthropometric laboratory". The school medical othcer and the natural science 

 nuister took the measurements: namely weight, stature, horizontal circum- 

 ference of the head, chest girth, girth of the flexed arm over the biceps muscle, 

 girth of the leg over the calf, both the last two being the maximum measure- 

 ments. The ages of the boys ranged from 10 to 19 and there were 550 of 

 them. The authors of the paper give three correlation tables for age with 

 stature, weight and head circumference, but make no reductions, citing merely 

 in the case of the extreme boys in each measurement the other mefvsure- 

 ments of those boys. One remark deserves citing. The authors state that they 



"are unaWe to trace any distinct connection between intellectual vigour and head measure- 

 ment ; for although many of those who possess the higher girths of head are intelligent Iwys 

 of considerable aV)ility, it must be confessed that many boys whose heads measure less than 

 22 inches, are in ability, perseverance, and general culture, quite equal to those who possess 

 the higher measurements." (p. 129.) 



This remark bears on a point already referred to in this Life (p. 94). 



Galtoii's short accompanying paper confines itself to one character, stature, 

 and he tells us that he proposes to illustrate the statistical methods which 

 will be adopted, when sufficient material of a homogeneous nature is available. 

 He takes the boys for each year of age and finds their means, which give 

 for the central ages 12^, 13^, etc. the law of growth. He thus obtains what 

 we should now term the regression line. But here he strikes a new point: 

 he finds that the arithmetical means of the arrays are not identical with 



' See our p. 125. 



* "On a Series of Measurements for Statistical Purposes, recently made at Marlborough 

 College." I?y Walter Fergus, M.D., and 0. F. Rodwell, F'.R.A.S. JonnuU of the Anthropo- 

 logical Institute, Vol. iv, pp. 126-30. "Notes on the Marlborough School Statistics" by 

 Francis Galton himself follow this paper, pp. 130-5. 



