OBSERVATIONS AND MEASUREMENTS ACADEMY MEMBERS 



[Memoirs National 

 [Vol. XXIII, 



nevertheless, groups of 100 and even 50 may safely be expected to show definite trends both 

 physically or physiologically. 



But another serious factor intrudes into both of the groups and that is the advanced age 

 of most of the individuals composing the membership. Except mentally, normal adult life 

 culminates around 50, after which inexorable senility begins to set in; and senility affects pro- 

 gressively nearly all the features and functions of the body. 



The results of the study of the members of the Academy are thus necessarily more or less 

 biased by the factor of age. 4 This must be borne in mind throughout their comparison with 

 the data on the old Americans at large, a series that comprised numerous young to middle-aged 

 adults and from which all subjects showing senile changes were excluded. Notwithstanding 

 this serious obstacle, however, a certain amount of useful comparison will be possible. 



The measurements and observations were taken by the methods and with instruments 

 described in my Anthropometry 6 and in The Old Americans. 6 To obviate any possible mis- 

 understanding an explanation of the measurement and procedure will be given under each 

 determination. 



AGE 



The mean age of the 150 members of the Academy who were examined was 59.67 years. 

 The mean age of the total membership of the Academy from 1920 to 1927 7 ranged from 58.94 

 to 61.10, with the general average of 59.96. It is evident that the group measured showed no 

 bias in age. 



A more detailed picture of the age distribution in those examined is given in table 1. On 

 the whole there is but a small difference between the two series, i. e., between the members of 

 old and those of more recent American status. On closer inspection the old Americans in the 

 series are seen to include a larger proportion of individuals of 60 or less, the not old Americans 

 a larger proportion of those above 60. 



The ranges of ages in both series are very extensive. They amount to 81.5 percent of the 

 average in the 100 old Americans, and to 65.3 percent in the other 50 members. 



Table 1 . — Members of the Academy: Ages 

 ALL MEMBERS 



' The effects of this factor on measurements were discussed by me recently before the American Philosophical Society: V. Growth During Adult 

 Life, Proc. Am. Philos. Soc, 1936, LXXVI, 847-897. 



• Wistar Institute, Philadelphia. 1920, new ed.: Practical Anthropometry, ibid., 1939. 



• Baltimore, 1925. 



7 Data furnished by Paul Brockett, Executive Secretary. 



