Academy of Sciences] 

 No. 3] 



MEASUREMENTS 



35 



HEAD SIZE 



The size of the head as a whole is most conveniently expressed by the mean of its three 



principal diameters, or "head module" — ■ The same object could be achieved by 



o 



calculating, by the formula of Pearson or others, the cranial capacity, but the procedure in such 



a case is very much more laborious and the results offer no compensatory value. 



The size of the head of the old Americans at large, excepting the belated mountaineers, 



was found to be larger than that of any of 12 nationalistic groups of immigrants measured at 



their entrance to New York, and that absolutely, as well as relatively to stature, when taken 



with statures of similar value. 26 The heads of the academicians of both groups, as will be seen 



below, are even larger: 



Table 29. — Cephalic module 



Members of the Academy 



Old Americans 



Not old 

 Americans 



Old Americans 

 at large 



Subjects 



Average 



Minimum 



Maximum 



Range of variation in percentage of the average 



100 

 16.51 

 15. 50 



17. 60 



18. 08 



50 



16.57 

 15. 82 



17.48 

 10.02 



594 



» 16. 37 



15. 03 



17. 70 

 16.31 



DISTRIBUTION 



Old Americans (100) 



Not old Americans (50) . 



15.50-15.76 



Percent 



2 



16.76-16 



Percent 



13 

 4 



16.01-16.25 16.26-16.50 



Percent 



18 

 14 



Percent 

 16 

 24 



Percent 

 19 



24 



16.76-17 



Percent 

 20 

 28 



Percent 

 7 

 4 



17.26-17.50 



Percent 

 3 

 2 



17.61-17.60 



Percent 

 2 



> Id the 247 laboratory subjects 16.39. 



The essential point shown by the above results, and by the charts, is that the head in the 

 members of the Academy, regardless of provenience, is larger than that of the old Americans at 

 large, even of those of the "laboratory series" which included a good many men of higher education. 

 The excess is limited to the dimensions of length and breadth. The difference would in all prob- 

 ability be even more pronounced if the brains could be compared direct, for everything points to 

 the fact that the skulls of the academicians are not merely larger outside, but in general also more 

 delicate, thinner, and hence additionally more spacious. All this tends to show that high mental 

 activity either goes on hereditary basis with a large brain and head, or, which is more likely, 

 that such activity favors the development of the brain. As intensive mental work means greater 

 than ordinary blood supply to the brain, the enlargement of the organ may be conceived to be due 

 to that agency, though just what grows or increases, whether the supporting and nourishing parts 

 alone, or also the higher cellular constituents, is as yet uncertain. 



The above facts may further be demonstrated through comparison of the mean diameter of 

 the head (cephalic module) with stature. The data and charts are as follows: 



» See the Old Americans, pp. 152, 193-5. 



